optimizations

Co-authored-by: Kasey Kirkham <kasey@users.noreply.github.com>

.bazelversion

@@ -1 +1 @@
-7.1.0
+7.4.1

.buildkite-bazelrc

@@ -50,7 +50,7 @@ build:nostamp --nostamp
 
 # Build metadata
 build --build_metadata=ROLE=CI
-build --build_metadata=REPO_URL=https://github.com/prysmaticlabs/prysm.git
+build --build_metadata=REPO_URL=https://github.com/OffchainLabs/prysm.git
 build --workspace_status_command=./hack/workspace_status_ci.sh
 
 # Buildbuddy

.deepsource.toml

@@ -11,7 +11,7 @@ name = "go"
 enabled = true
 
 [analyzers.meta]
-import_paths = ["github.com/prysmaticlabs/prysm/v5"]
+import_paths = ["github.com/OffchainLabs/prysm/v6"]
 
 [[analyzers]]
 name = "test-coverage"

.github/PULL_REQUEST_TEMPLATE.md

@@ -10,6 +10,7 @@
    in review.
 4. Note that PRs updating dependencies and new Go versions are not accepted.
    Please file an issue instead.
+5. A changelog entry is required for user facing issues.
 -->
 
 **What type of PR is this?**
@@ -28,3 +29,9 @@
 Fixes #
 
 **Other notes for review**
+
+**Acknowledgements**
+
+- [ ] I have read [CONTRIBUTING.md](https://github.com/prysmaticlabs/prysm/blob/develop/CONTRIBUTING.md).
+- [ ] I have included a uniquely named [changelog fragment file](https://github.com/prysmaticlabs/prysm/blob/develop/CONTRIBUTING.md#maintaining-changelogmd).
+- [ ] I have added a description to this PR with sufficient context for reviewers to understand this PR.

.github/actions/gomodtidy/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.22-alpine
+FROM golang:1.24-alpine
 
 COPY entrypoint.sh /entrypoint.sh
 

.github/workflows/changelog.yml

@@ -0,0 +1,34 @@
+# This workflow will build a golang project
+# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-go
+
+name: changelog
+
+on:
+  pull_request:
+    branches: [ "develop" ]
+
+jobs:
+  run-changelog-check:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout source code
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0
+
+      - name: Download unclog binary
+        uses: dsaltares/fetch-gh-release-asset@aa2ab1243d6e0d5b405b973c89fa4d06a2d0fff7 # 1.1.2
+        with:
+          repo: OffchainLabs/unclog
+          version: "tags/v0.1.5"
+          file: "unclog"
+
+      - name: Get new changelog files
+        id: new-changelog-files
+        uses: OffchainLabs/gh-action-changed-files@9200e69727eb73eb060652b19946b8a2fdfb654b # v4.0.8
+        with:
+          files: |
+            changelog/**.md
+
+      - name: Run lint command
+        env:
+          ALL_ADDED_MARKDOWN: ${{ steps.new-changelog-files.outputs.added_files }}
+        run: chmod +x unclog && ./unclog check -fragment-env=ALL_ADDED_MARKDOWN

.github/workflows/clang-format.yml

@@ -0,0 +1,21 @@
+name: Protobuf Format
+
+on: 
+  push:
+    branches: [ '*' ]
+  pull_request:
+    branches: [ '*' ]
+  merge_group:
+    types: [checks_requested]
+
+jobs:
+  clang-format-checking:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      # Is this step failing for you? 
+      # Run: clang-format -i proto/**/*.proto
+      # See: https://clang.llvm.org/docs/ClangFormat.html
+      - uses: RafikFarhad/clang-format-github-action@v3
+        with:
+          sources: "proto/**/*.proto"

.github/workflows/fuzz.yml

@@ -16,7 +16,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions/setup-go@v4
         with:
-          go-version: '1.22.3'
+          go-version: '1.23.5'
       - id: list
         uses: shogo82148/actions-go-fuzz/list@v0
         with:
@@ -36,7 +36,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: actions/setup-go@v4
         with:
-          go-version: '1.22.3'
+          go-version: '1.23.5'
       - uses: shogo82148/actions-go-fuzz/run@v0
         with:
           packages: ${{ matrix.package }}

.github/workflows/go.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Go mod tidy checker
         id: gomodtidy
@@ -27,34 +27,34 @@ jobs:
       GO111MODULE: on
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
-      - name: Set up Go 1.22
-        uses: actions/setup-go@v3
+        uses: actions/checkout@v4
+      - name: Set up Go 1.24
+        uses: actions/setup-go@v4
         with:
-          go-version: '1.22.3'
+          go-version: '1.24.0'
       - name: Run Gosec Security Scanner
         run: | # https://github.com/securego/gosec/issues/469
           export PATH=$PATH:$(go env GOPATH)/bin
-          go install github.com/securego/gosec/v2/cmd/gosec@v2.19.0
-          gosec -exclude-generated -exclude=G307 -exclude-dir=crypto/bls/herumi ./...
+          go install github.com/securego/gosec/v2/cmd/gosec@v2.22.1
+          gosec -exclude-generated -exclude=G307,G115 -exclude-dir=crypto/bls/herumi ./...
 
   lint:
     name: Lint
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
-      - name: Set up Go 1.22
-        uses: actions/setup-go@v3
+      - name: Set up Go 1.24
+        uses: actions/setup-go@v4
         with:
-          go-version: '1.22.3'
+          go-version: '1.24.0'
           id: go
 
       - name: Golangci-lint
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v5
         with:
-          version: v1.55.2
+          version: v1.64.5
           args: --config=.golangci.yml --out-${NO_FUTURE}format colored-line-number
 
   build:
@@ -62,13 +62,13 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Set up Go 1.x
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v4
         with:
-          go-version: '1.22.3'
+          go-version: '1.24.0'
         id: go
 
       - name: Check out code into the Go module directory
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Get dependencies
         run: |

.golangci.yml

@@ -1,28 +1,20 @@
 run:
-  skip-files:
+  timeout: 10m
+  go: '1.23.5'
+
+issues:
+  exclude-files:
     - validator/web/site_data.go
     - .*_test.go
-  skip-dirs:
+  exclude-dirs:
     - proto
     - tools/analyzers
-  timeout: 10m
-  go: '1.22.3'
 
 linters:
   enable-all: true
   disable:
     # Deprecated linters:
-    - deadcode
-    - exhaustivestruct
-    - golint
     - govet
-    - ifshort
-    - interfacer
-    - maligned
-    - nosnakecase
-    - scopelint
-    - structcheck
-    - varcheck
 
     # Disabled for now:
     - asasalint
@@ -34,6 +26,8 @@ linters:
     - dogsled
     - dupl
     - durationcheck
+    - errname
+    - err113
     - exhaustive
     - exhaustruct
     - forbidigo
@@ -47,17 +41,17 @@ linters:
     - gocyclo
     - godot
     - godox
-    - goerr113
     - gofumpt
-    - gomnd
     - gomoddirectives
     - gosec
     - inamedparam
     - interfacebloat
+    - intrange
     - ireturn
     - lll
     - maintidx
     - makezero
+    - mnd
     - musttag
     - nakedret
     - nestif
@@ -72,13 +66,16 @@ linters:
     - predeclared
     - promlinter
     - protogetter
+    - recvcheck
     - revive
+    - spancheck
     - staticcheck
     - stylecheck
     - tagalign
     - tagliatelle
     - thelper
     - unparam
+    - usetesting
     - varnamelen
     - wrapcheck
     - wsl

.policy.yml

@@ -26,7 +26,6 @@ approval_rules:
       only_changed_files:
         paths:
           - "*pb.go"
-          - "*pb.gw.go"
           - "*.bazel"
     options:
       ignore_commits_by:
@@ -69,7 +68,6 @@ approval_rules:
       changed_files:
         ignore:
           - "*pb.go"
-          - "*pb.gw.go"
           - "*.bazel"
     options:
       ignore_commits_by:

.travis.yml

@@ -1,5 +1,5 @@
 language: go
-go_import_path: github.com/prysmaticlabs/prysm
+go_import_path: github.com/OffchainLabs/prysm
 sudo: false
 matrix:
   include:

BUILD.bazel

@@ -6,13 +6,13 @@ load("@io_bazel_rules_go//go:def.bzl", "nogo")
 load("@bazel_skylib//rules:common_settings.bzl", "string_setting")
 load("@prysm//tools/nogo_config:def.bzl", "nogo_config_exclude")
 
-prefix = "github.com/prysmaticlabs/prysm"
+prefix = "github.com/OffchainLabs/prysm"
 
 exports_files([
     "LICENSE.md",
 ])
 
-# gazelle:prefix github.com/prysmaticlabs/prysm/v5
+# gazelle:prefix github.com/OffchainLabs/prysm/v6
 # gazelle:map_kind go_library go_library @prysm//tools/go:def.bzl
 # gazelle:map_kind go_test go_test @prysm//tools/go:def.bzl
 # gazelle:map_kind go_repository go_repository @prysm//tools/go:def.bzl
@@ -55,13 +55,6 @@ alias(
     visibility = ["//visibility:public"],
 )
 
-# Protobuf gRPC gateway compiler
-alias(
-    name = "grpc_gateway_proto_compiler",
-    actual = "@com_github_grpc_ecosystem_grpc_gateway_v2//protoc-gen-grpc-gateway:go_gen_grpc_gateway",
-    visibility = ["//visibility:public"],
-)
-
 gometalinter(
     name = "gometalinter",
     config = "//:.gometalinter.json",
@@ -172,7 +165,7 @@ STATICCHECK_ANALYZERS = [
     "sa6006",
     "sa9001",
     "sa9002",
-    #"sa9003", # Doesn't build. See https://github.com/dominikh/go-tools/pull/1483
+    "sa9003",
     "sa9004",
     "sa9005",
     "sa9006",
@@ -201,9 +194,11 @@ nogo(
         "//tools/analyzers/gocognit:go_default_library",
         "//tools/analyzers/ineffassign:go_default_library",
         "//tools/analyzers/interfacechecker:go_default_library",
+        "//tools/analyzers/logcapitalization:go_default_library",
         "//tools/analyzers/logruswitherror:go_default_library",
         "//tools/analyzers/maligned:go_default_library",
         "//tools/analyzers/nop:go_default_library",
+        "//tools/analyzers/nopanic:go_default_library",
         "//tools/analyzers/properpermissions:go_default_library",
         "//tools/analyzers/recursivelock:go_default_library",
         "//tools/analyzers/shadowpredecl:go_default_library",

CONTRIBUTING.md

@@ -4,7 +4,10 @@ Note: The latest and most up-to-date documentation can be found on our [docs por
 
 Excited by our work and want to get involved in building out our sharding releases? Or maybe you haven't learned as much about the Ethereum protocol but are a savvy developer? 
 
-You can explore our [Open Issues](https://github.com/prysmaticlabs/prysm/issues) in-the works for our different releases. Feel free to fork our repo and start creating PR’s after assigning yourself to an issue of interest. We are always chatting on [Discord](https://discord.gg/CTYGPUJ) drop us a line there if you want to get more involved or have any questions on our implementation!
+You can explore our [Open Issues](https://github.com/OffchainLabs/prysm/issues) in-the works for our different releases. Feel free to fork our repo and start creating PR’s after assigning yourself to an issue of interest. We are always chatting on [Discord](https://discord.gg/prysm) drop us a line there if you want to get more involved or have any questions on our implementation!
+
+> [!IMPORTANT] 
+> Please, **do not send pull requests for trivial changes**, such as typos, these will be rejected. These types of pull requests incur a cost to reviewers and do not provide much value to the project. If you are unsure, please open an issue first to discuss the change.
 
 ## Contribution Steps
 
@@ -12,15 +15,15 @@ You can explore our [Open Issues](https://github.com/prysmaticlabs/prysm/issues)
 
 **2. Fork the Prysm repo.**
 
-Sign in to your GitHub account or create a new account if you do not have one already. Then navigate your browser to https://github.com/prysmaticlabs/prysm/. In the upper right hand corner of the page, click “fork”. This will create a copy of the Prysm repo in your account.
+Sign in to your GitHub account or create a new account if you do not have one already. Then navigate your browser to https://github.com/OffchainLabs/prysm/. In the upper right hand corner of the page, click “fork”. This will create a copy of the Prysm repo in your account.
 
 **3. Create a local clone of Prysm.**
 
 ```
-$ mkdir -p $GOPATH/src/github.com/prysmaticlabs
-$ cd $GOPATH/src/github.com/prysmaticlabs
-$ git clone https://github.com/prysmaticlabs/prysm.git
-$ cd $GOPATH/src/github.com/prysmaticlabs/prysm
+$ mkdir -p $GOPATH/src/github.com/OffchainLabs
+$ cd $GOPATH/src/github.com/OffchainLabs
+$ git clone https://github.com/OffchainLabs/prysm.git
+$ cd $GOPATH/src/github.com/OffchainLabs/prysm
 ```
 
 **4. Link your local clone to the fork on your GitHub repo.**
@@ -32,13 +35,13 @@ $ git remote add myprysmrepo https://github.com/<your_github_user_name>/prysm.gi
 **5. Link your local clone to the Prysmatic Labs repo so that you can easily fetch future changes to the Prysmatic Labs repo.**
 
 ```
-$ git remote add prysm https://github.com/prysmaticlabs/prysm.git
+$ git remote add prysm https://github.com/OffchainLabs/prysm.git
 $ git remote -v (you should see myrepo and prysm in the list of remotes)
 ```
 
 **6. Find an issue to work on.**
 
-Check out open issues at https://github.com/prysmaticlabs/prysm/issues and pick one. Leave a comment to let the development team know that you would like to work on it. Or examine the code for areas that can be improved and leave a comment to the development team to ask if they would like you to work on it.
+Check out open issues at https://github.com/OffchainLabs/prysm/issues and pick one. Leave a comment to let the development team know that you would like to work on it. Or examine the code for areas that can be improved and leave a comment to the development team to ask if they would like you to work on it.
 
 **7. Create a local branch with a name that clearly identifies what you will be working on.**
 
@@ -120,15 +123,19 @@ $ git push myrepo feature-in-progress-branch
 
 Navigate to your fork of the repo on GitHub. On the upper left where the current branch is listed, change the branch to your feature-in-progress-branch. Open the files that you have worked on and check to make sure they include your changes.
 
-**16. Create a pull request.**
+**16. Add an entry to CHANGELOG.md.**
 
-Navigate your browser to https://github.com/prysmaticlabs/prysm and click on the new pull request button. In the “base” box on the left, leave the default selection “base master”, the branch that you want your changes to be applied to. In the “compare” box on the right, select feature-in-progress-branch, the branch containing the changes you want to apply. You will then be asked to answer a few questions about your pull request. After you complete the questionnaire, the pull request will appear in the list of pull requests at https://github.com/prysmaticlabs/prysm/pulls.
+All PRs must must include a changelog fragment file in the `changelog` directory. If your change is not user-facing or should not be mentioned in the changelog for some other reason, you may use the `Ignored` changelog section in your fragment's header to satisfy this requirement without altering the final release changelog. See the [Maintaining CHANGELOG.md](#maintaining-changelogmd) section for more information.
 
-**17. Respond to comments by Core Contributors.**
+**17. Create a pull request.**
+
+Navigate your browser to https://github.com/OffchainLabs/prysm and click on the new pull request button. In the “base” box on the left, leave the default selection “base develop”, the branch that you want your changes to be applied to. In the “compare” box on the right, select feature-in-progress-branch, the branch containing the changes you want to apply. You will then be asked to answer a few questions about your pull request. After you complete the questionnaire, the pull request will appear in the list of pull requests at https://github.com/OffchainLabs/prysm/pulls. Ensure that you have added an entry to CHANGELOG.md if your PR is a user-facing change. See the [Maintaining CHANGELOG.md](#maintaining-changelogmd) section for more information.
+
+**18. Respond to comments by Core Contributors.**
 
 Core Contributors may ask questions and request that you make edits. If you set notifications at the top of the page to “not watching,” you will still be notified by email whenever someone comments on the page of a pull request you have created. If you are asked to modify your pull request, repeat steps 8 through 15, then leave a comment to notify the Core Contributors that the pull request is ready for further review.
 
-**18. If the number of commits becomes excessive, you may be asked to squash your commits.**
+**19. If the number of commits becomes excessive, you may be asked to squash your commits.**
 
  You can do this with an interactive rebase. Start by running the following command to determine the commit that is the base of your branch...
 
@@ -136,7 +143,7 @@ Core Contributors may ask questions and request that you make edits. If you set
 $ git merge-base feature-in-progress-branch prysm/master
 ```
 
-**19. The previous command will return a commit-hash that you should use in the following command.**
+**20. The previous command will return a commit-hash that you should use in the following command.**
 
 ```
 $ git rebase -i commit-hash
@@ -160,13 +167,24 @@ squash  hash 	add a feature
 
 Save and close the file, then a commit command will appear in the terminal that squashes the smaller commits into one. Check to be sure the commit message accurately reflects your changes and then hit enter to execute it.
 
-**20. Update your pull request with the following command.**
+**21. Update your pull request with the following command.**
 
 ```
 $ git push myrepo feature-in-progress-branch -f
 ```
 
-**21.  Finally, again leave a comment to the Core Contributors on the pull request to let them know that the pull request has been updated.**
+**22.  Finally, again leave a comment to the Core Contributors on the pull request to let them know that the pull request has been updated.**
+
+## Maintaining CHANGELOG.md
+
+This project follows the changelog guidelines from [keepachangelog.com](https://keepachangelog.com/en/1.1.0/). In order to minimize conflicts and workflow headaches, we chose to implement a changelog management
+strategy that uses changelog "fragment" files, managed by our changelog management tool called `unclog`. Each PR must include a new changelog fragment file in the `changelog` directory, as specified by unclog's
+[README.md](https://github.com/OffchainLabs/unclog?tab=readme-ov-file#what-is-a-changelog-fragment). As the `unclog` README suggests in the [Best Practices](https://github.com/OffchainLabs/unclog?tab=readme-ov-file#best-practices) section, 
+the standard naming convention for your PR's fragment file, to avoid conflicting with another fragment file, is `changelog/<github user name>_<PR branch name>.md`.
+
+### Releasing
+
+When a new release is made, the "Unreleased" section should be moved to a new section with the release version and the current date. Then a new "Unreleased" section is made at the top of the file with the categories listed above.
 
 ## Contributor Responsibilities
 

DEPENDENCIES.md

@@ -2,7 +2,7 @@
 
 Prysm is go project with many complicated dependencies, including some c++ based libraries. There
 are two parts to Prysm's dependency management. Go modules and bazel managed dependencies. Be sure 
-to read [Why Bazel?](https://github.com/prysmaticlabs/documentation/issues/138) to fully
+to read [Why Bazel?](https://github.com/OffchainLabs/documentation/issues/138) to fully
 understand the reasoning behind an additional layer of build tooling via Bazel rather than a pure
 "go build" project.
 
@@ -55,12 +55,12 @@ bazel build //beacon-chain --config=release
 ## Adding / updating dependencies
 
 1. Add your dependency as you would with go modules. I.e. `go get ...`
-1. Run `bazel run //:gazelle -- update-repos -from_file=go.mod` to update the bazel managed dependencies.
+1. Run `bazel run //:gazelle -- update-repos -from_file=go.mod -to_macro=deps.bzl%prysm_deps -prune=true` to update the bazel managed dependencies.
 
 Example:
 
 ```bash
-go get github.com/prysmaticlabs/example@v1.2.3
+go get github.com/OffchainLabs/example@v1.2.3
 bazel run //:gazelle -- update-repos -from_file=go.mod -to_macro=deps.bzl%prysm_deps -prune=true
 ```
 

INTEROP.md

@@ -2,18 +2,21 @@
 
 This README details how to setup Prysm for interop testing for usage with other Ethereum consensus clients.
 
+> [!IMPORTANT]  
+> This guide is likely to be outdated. The Prysm team does not have capacity to troubleshoot
+> outdated interop guides or instructions. If you experience issues with this guide, please file an
+> issue for visibility and propose fixes, if possible.
+
 ## Installation & Setup
 
 1. Install [Bazel](https://docs.bazel.build/versions/master/install.html) **(Recommended)**
-2. `git clone https://github.com/prysmaticlabs/prysm && cd prysm`
-3. `bazel build //...`
+2. `git clone https://github.com/OffchainLabs/prysm && cd prysm`
+3. `bazel build //cmd/...`
 
 ## Starting from Genesis
 
-Prysm supports a few ways to quickly launch a beacon node from basic configurations:
-
-- `NumValidators + GenesisTime`: Launches a beacon node by deterministically generating a state from a num-validators flag along with a genesis time **(Recommended)**
-- `SSZ Genesis`: Launches a beacon node  from a .ssz file containing a SSZ-encoded, genesis beacon state
+Prysm can be started from a built-in mainnet genesis state, or started with a provided genesis state by
+using the `--genesis-state` flag and providing a path to the genesis.ssz file.
 
 ## Generating a Genesis State
 
@@ -21,21 +24,34 @@ To setup the necessary files for these quick starts, Prysm provides a tool to ge
 a deterministically generated set of validator private keys following the official interop YAML format 
 [here](https://github.com/ethereum/eth2.0-pm/blob/master/interop/mocked_start).
 
-You can use `bazel run //tools/genesis-state-gen` to create a deterministic genesis state for interop.
+You can use `prysmctl` to create a deterministic genesis state for interop.
 
-### Usage
-
-- **--genesis-time** uint: Unix timestamp used as the genesis time in the generated genesis state (defaults to now)
-- **--num-validators** int: Number of validators to deterministically include in the generated genesis state
-- **--output-ssz** string: Output filename of the SSZ marshaling of the generated genesis state
-- **--config-name=interop** string: name of the beacon chain config to use when generating the state. ex mainnet|minimal|interop
-
-The example below creates 64 validator keys, instantiates a genesis state with those 64 validators and with genesis unix timestamp 1567542540,
-and finally writes a ssz encoded output to ~/Desktop/genesis.ssz. This file can be used to kickstart the beacon chain in the next section. When using the `--interop-*` flags, the beacon node will assume the `interop` config should be used, unless a different config is specified on the command line.
+```sh
+# Download (or create) a chain config file.
+curl https://raw.githubusercontent.com/ethereum/consensus-specs/refs/heads/dev/configs/minimal.yaml -o /tmp/minimal.yaml
 
+# Run prysmctl to generate genesis with a 2 minute genesis delay and 256 validators. 
+bazel run //cmd/prysmctl --config=minimal -- \
+  testnet generate-genesis \
+  --genesis-time-delay=120 \
+  --num-validators=256 \
+  --output-ssz=/tmp/genesis.ssz \
+  --chain-config-file=/tmp/minimal.yaml
 ```
-bazel run //tools/genesis-state-gen -- --config-name interop --output-ssz ~/Desktop/genesis.ssz --num-validators 64 --genesis-time 1567542540
-```
+
+The flags are explained below:
+- `bazel run //cmd/prysmctl` is the bazel command to compile and run prysmctl.
+- `--config=minimal` is a bazel build time configuration flag to compile Prysm with minimal state constants.
+- `--` is an argument divider to tell bazel that everything after this divider should be passed as arguments to prysmctl. Without this divider, it isn't clear to bazel if the arguments are meant to be build time arguments or runtime arguments so the operation complains and fails to build without this divider.
+- `testnet` is the primary command argument for prysmctl.
+- `generate-genesis` is the subcommand to `testnet` in prysmctl.
+- `--genesis-time-delay` uint: The number of seconds in the future to define genesis. Example: a value of 60 will set the genesis time to 1 minute in the future. This should be sufficiently large enough to allow for you to start the beacon node before the genesis time. 
+- `--num-validators` int: Number of validators to deterministically include in the generated genesis state
+- `--output-ssz` string: Output filename of the SSZ marshaling of the generated genesis state
+- `--chain-config-file` string: Filepath to a chain config yaml file.
+
+Note: This guide saves items to the `/tmp/` directory which will not persist if your machine is
+restarted. Consider tweaking the arguments if persistence is needed.
 
 ## Launching a Beacon Node + Validator Client
 
@@ -44,45 +60,33 @@ bazel run //tools/genesis-state-gen -- --config-name interop --output-ssz ~/Desk
 Open up two terminal windows, run:
 
 ```
-bazel run //beacon-chain -- \
---bootstrap-node= \
---deposit-contract 0x8A04d14125D0FDCDc742F4A05C051De07232EDa4 \
---datadir=/tmp/beacon-chain-interop \
---force-clear-db \
---min-sync-peers=0 \
---interop-num-validators 64 \
---interop-eth1data-votes
+bazel run //cmd/beacon-chain --config=minimal -- \
+  --minimal-config \
+  --bootstrap-node= \
+  --deposit-contract 0x8A04d14125D0FDCDc742F4A05C051De07232EDa4 \
+  --datadir=/tmp/beacon-chain-minimal-devnet \
+  --force-clear-db \
+  --min-sync-peers=0 \
+  --genesis-state=/tmp/genesis.ssz \
+  --chain-config-file=/tmp/minimal.yaml
 ```
 
-This will deterministically generate a beacon genesis state and start
-the system with 64 validators and the genesis time set to the current unix timestamp.
-Wait a bit until your beacon chain starts, and in the other window:
+This will start the system with 256 validators. The flags used can be explained as such:
+
+- `bazel run //cmd/beacon-chain --config=minimal` builds and runs the beacon node in minimal build configuration.
+- `--` is a flag divider to distinguish between bazel flags and flags that should be passed to the application. All flags and arguments after this divider are passed to the beacon chain.
+- `--minimal-config` tells the beacon node to use minimal network configuration. This is different from the compile time state configuration flag `--config=minimal` and both are required.
+- `--bootstrap-node=` disables the default bootstrap nodes. This prevents the client from attempting to peer with mainnet nodes.
+- `--datadir=/tmp/beacon-chain-minimal-devnet` sets the data directory in a temporary location. Change this to your preferred destination.
+- `--force-clear-db` will delete the beaconchain.db file without confirming with the user. This is helpful for iteratively running local devnets without changing the datadir, but less helpful for one off runs where there was no database in the data directory.
+- `--min-sync-peers=0` allows the beacon node to skip initial sync without peers. This is essential because Prysm expects at least a few peers to start the blockchain.
+- `--genesis-state=/tmp/genesis.ssz` defines the path to the generated genesis ssz file. The beacon node will use this as the initial genesis state.
+- `--chain-config-file=/tmp/minimal.yaml` defines the path to the yaml file with the chain configuration.
+
+As soon as the beacon node has started, start the validator in the other terminal window. 
 
 ```
-bazel run //validator -- --keymanager=interop --keymanageropts='{"keys":64}'
+bazel run //cmd/validator --config=minimal -- --datadir=/tmp/validator --interop-num-validators=256 --minimal-config --suggested-fee-recipient=0x8A04d14125D0FDCDc742F4A05C051De07232EDa4
 ```
 
-This will launch and kickstart the system with your 64 validators performing their duties accordingly.
-
-### Launching from `genesis.ssz`
-
-Assuming you generated a `genesis.ssz` file with 64 validators, open up two terminal windows, run:
-
-```
- bazel run //beacon-chain -- \
---bootstrap-node= \
---deposit-contract 0x8A04d14125D0FDCDc742F4A05C051De07232EDa4 \
---datadir=/tmp/beacon-chain-interop \
---force-clear-db \
---min-sync-peers=0 \
---interop-genesis-state /path/to/genesis.ssz \
---interop-eth1data-votes
-```
-
-Wait a bit until your beacon chain starts, and in the other window:
-
-```
-bazel run //validator -- --keymanager=interop --keymanageropts='{"keys":64}'
-```
-
-This will launch and kickstart the system with your 64 validators performing their duties accordingly.
+This will launch and kickstart the system with your 256 validators performing their duties accordingly.

README.md

@@ -1,37 +1,68 @@
-# Prysm: An Ethereum Consensus Implementation Written in Go
+<h1 align="left">Prysm: An Ethereum Consensus Implementation Written in Go</h1>
 
+<div align="left">
+  
 [![Build status](https://badge.buildkite.com/b555891daf3614bae4284dcf365b2340cefc0089839526f096.svg?branch=master)](https://buildkite.com/prysmatic-labs/prysm)
-[![Go Report Card](https://goreportcard.com/badge/github.com/prysmaticlabs/prysm)](https://goreportcard.com/report/github.com/prysmaticlabs/prysm)
+[![Go Report Card](https://goreportcard.com/badge/github.com/OffchainLabs/prysm)](https://goreportcard.com/report/github.com/OffchainLabs/prysm)
 [![Consensus_Spec_Version 1.4.0](https://img.shields.io/badge/Consensus%20Spec%20Version-v1.4.0-blue.svg)](https://github.com/ethereum/consensus-specs/tree/v1.4.0)
 [![Execution_API_Version 1.0.0-beta.2](https://img.shields.io/badge/Execution%20API%20Version-v1.0.0.beta.2-blue.svg)](https://github.com/ethereum/execution-apis/tree/v1.0.0-beta.2/src/engine)
-[![Discord](https://user-images.githubusercontent.com/7288322/34471967-1df7808a-efbb-11e7-9088-ed0b04151291.png)](https://discord.gg/prysmaticlabs)
-[![GitPOAP Badge](https://public-api.gitpoap.io/v1/repo/prysmaticlabs/prysm/badge)](https://www.gitpoap.io/gh/prysmaticlabs/prysm)
+[![Discord](https://user-images.githubusercontent.com/7288322/34471967-1df7808a-efbb-11e7-9088-ed0b04151291.png)](https://discord.gg/prysm)
+[![GitPOAP Badge](https://public-api.gitpoap.io/v1/repo/OffchainLabs/prysm/badge)](https://www.gitpoap.io/gh/OffchainLabs/prysm)
 
-This is the core repository for Prysm, a [Golang](https://golang.org/) implementation of the [Ethereum Consensus](https://ethereum.org/en/developers/docs/consensus-mechanisms/#proof-of-stake) [specification](https://github.com/ethereum/consensus-specs), developed by [Offchain Labs](https://www.offchainlabs.com). See the [Changelog](https://github.com/prysmaticlabs/prysm/releases) for details of the latest releases and upcoming breaking changes.
+</div>
 
-### Getting Started
+---
 
-A detailed set of installation and usage instructions as well as breakdowns of each individual component are available in the [official documentation portal](https://docs.prylabs.network). If you still have questions, feel free to stop by our [Discord](https://discord.gg/prysmaticlabs).
+## 📖 Overview
 
-### Staking on Mainnet
+This is the core repository for Prysm, a [Golang](https://golang.org/) implementation of the [Ethereum Consensus](https://ethereum.org/en/developers/docs/consensus-mechanisms/#proof-of-stake) [specification](https://github.com/ethereum/consensus-specs), developed by [Offchain Labs](https://www.offchainlabs.com).
 
-To participate in staking, you can join the [official eth2 launchpad](https://launchpad.ethereum.org). The launchpad is the only recommended way to become a validator on mainnet. You can explore validator rewards/penalties via Bitfly's block explorer: [beaconcha.in](https://beaconcha.in), and follow the latest blocks added to the chain on [beaconscan](https://beaconscan.com).
+See the [Changelog](https://github.com/OffchainLabs/prysm/releases) for details of the latest releases and upcoming breaking changes.
 
+---
+
+## 🚀 Getting Started
+
+A detailed set of installation and usage instructions as well as breakdowns of each individual component are available in the **[official documentation portal](https://docs.prylabs.network)**.
+
+💬 **Need help?** Join our **[Discord Community](https://discord.gg/prysm)** for support.
+
+---
+
+## 🏆 Staking on Mainnet
+
+To participate in staking, you can join the **[official Ethereum launchpad](https://launchpad.ethereum.org)**. The launchpad is the **only recommended** way to become a validator on mainnet.
+
+🔍 Explore validator rewards/penalties:
+
+- **[beaconcha.in](https://beaconcha.in)**
+- **[beaconscan](https://beaconscan.com)**
+
+---
+
+## 🤝 Contributing
+
+### 🔥 Branches
 
-## Contributing
-### Branches
 Prysm maintains two permanent branches:
 
-* [master](https://github.com/prysmaticlabs/prysm/tree/master): This points to the latest stable release. It is ideal for most users.
-* [develop](https://github.com/prysmaticlabs/prysm/tree/develop): This is used for development, it contains the latest PRs. Developers should base their PRs on this branch.
+- **[`master`](https://github.com/OffchainLabs/prysm/tree/master)** - This points to the latest stable release. It is ideal for most users.
+- **[`develop`](https://github.com/OffchainLabs/prysm/tree/develop)** - This is used for development and contains the latest PRs. Developers should base their PRs on this branch.
 
-### Guide
-Want to get involved? Check out our [Contribution Guide](https://docs.prylabs.network/docs/contribute/contribution-guidelines/) to learn more!
+### 🛠 Contribution Guide
 
-## License
+Want to get involved? Check out our **[Contribution Guide](https://docs.prylabs.network/docs/contribute/contribution-guidelines/)** to learn more!
 
-[GNU General Public License v3.0](https://www.gnu.org/licenses/gpl-3.0.en.html)
+---
 
-## Legal Disclaimer
+## 📜 License
 
-[Terms of Use](/TERMS_OF_SERVICE.md)
+[![License: GPL v3](https://img.shields.io/badge/License-GPLv3-blue.svg)](https://www.gnu.org/licenses/gpl-3.0.en.html)  
+
+This project is licensed under the **GNU General Public License v3.0**.
+
+---
+
+## ⚖️ Legal Disclaimer
+
+📜 [Terms of Use](/TERMS_OF_SERVICE.md)

SECURITY.md

@@ -2,10 +2,10 @@
 
 ## Supported Versions
 
-[Releases](https://github.com/prysmaticlabs/prysm/releases/) contains all available releases. We recommend using the [most recently released version](https://github.com/prysmaticlabs/prysm/releases/latest).
+[Releases](https://github.com/OffchainLabs/prysm/releases/) contains all available releases. We recommend using the [most recently released version](https://github.com/OffchainLabs/prysm/releases/latest).
 
 ## Reporting a Vulnerability
 
-Please see our signed [security.txt](https://github.com/prysmaticlabs/prysm/blob/develop/.well-known/security.txt) for preferred encryption and reporting destination.
+Please see our signed [security.txt](https://github.com/OffchainLabs/prysm/blob/develop/.well-known/security.txt) for preferred encryption and reporting destination.
 
 **Please do not file a public ticket** mentioning the vulnerability, as doing so could increase the likelihood of the vulnerability being used before a fix has been created, released and installed on the network.

WORKSPACE

@@ -1,7 +1,7 @@
 workspace(name = "prysm")
 
-load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
 http_archive(
     name = "rules_pkg",
@@ -16,6 +16,32 @@ load("@rules_pkg//:deps.bzl", "rules_pkg_dependencies")
 
 rules_pkg_dependencies()
 
+http_archive(
+    name = "toolchains_protoc",
+    sha256 = "abb1540f8a9e045422730670ebb2f25b41fa56ca5a7cf795175a110a0a68f4ad",
+    strip_prefix = "toolchains_protoc-0.3.6",
+    url = "https://github.com/aspect-build/toolchains_protoc/releases/download/v0.3.6/toolchains_protoc-v0.3.6.tar.gz",
+)
+
+load("@toolchains_protoc//protoc:repositories.bzl", "rules_protoc_dependencies")
+
+rules_protoc_dependencies()
+
+load("@rules_proto//proto:repositories.bzl", "rules_proto_dependencies")
+
+rules_proto_dependencies()
+
+load("@bazel_features//:deps.bzl", "bazel_features_deps")
+
+bazel_features_deps()
+
+load("@toolchains_protoc//protoc:toolchain.bzl", "protoc_toolchains")
+
+protoc_toolchains(
+    name = "protoc_toolchains",
+    version = "v25.3",
+)
+
 HERMETIC_CC_TOOLCHAIN_VERSION = "v3.0.1"
 
 http_archive(
@@ -101,9 +127,9 @@ http_archive(
 
 http_archive(
     name = "aspect_bazel_lib",
-    sha256 = "f5ea76682b209cc0bd90d0f5a3b26d2f7a6a2885f0c5f615e72913f4805dbb0d",
-    strip_prefix = "bazel-lib-2.5.0",
-    url = "https://github.com/aspect-build/bazel-lib/releases/download/v2.5.0/bazel-lib-v2.5.0.tar.gz",
+    sha256 = "a272d79bb0ac6b6965aa199b1f84333413452e87f043b53eca7f347a23a478e8",
+    strip_prefix = "bazel-lib-2.9.3",
+    url = "https://github.com/bazel-contrib/bazel-lib/releases/download/v2.9.3/bazel-lib-v2.9.3.tar.gz",
 )
 
 load("@aspect_bazel_lib//lib:repositories.bzl", "aspect_bazel_lib_dependencies", "aspect_bazel_lib_register_toolchains")
@@ -132,15 +158,15 @@ oci_register_toolchains(
 
 http_archive(
     name = "io_bazel_rules_go",
+    integrity = "sha256-JD8o94crTb2DFiJJR8nMAGdBAW95zIENB4cbI+JnrI4=",
     patch_args = ["-p1"],
     patches = [
         # Expose internals of go_test for custom build transitions.
         "//third_party:io_bazel_rules_go_test.patch",
     ],
-    sha256 = "80a98277ad1311dacd837f9b16db62887702e9f1d1c4c9f796d0121a46c8e184",
+    strip_prefix = "rules_go-cf3c3af34bd869b864f5f2b98e2f41c2b220d6c9",
     urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.46.0/rules_go-v0.46.0.zip",
-        "https://github.com/bazelbuild/rules_go/releases/download/v0.46.0/rules_go-v0.46.0.zip",
+        "https://github.com/bazel-contrib/rules_go/archive/cf3c3af34bd869b864f5f2b98e2f41c2b220d6c9.tar.gz",
     ],
 )
 
@@ -164,8 +190,8 @@ load("@rules_oci//oci:pull.bzl", "oci_pull")
 # A multi-arch base image
 oci_pull(
     name = "linux_debian11_multiarch_base",  # Debian bullseye
-    digest = "sha256:b82f113425c5b5c714151aaacd8039bc141821cdcd3c65202d42bdf9c43ae60b",  # 2023-12-12
-    image = "gcr.io/distroless/cc-debian11",
+    digest = "sha256:55a5e011b2c4246b4c51e01fcc2b452d151e03df052e357465f0392fcd59fddf",
+    image = "gcr.io/prysmaticlabs/distroless/cc-debian11",
     platforms = [
         "linux/amd64",
         "linux/arm64/v8",
@@ -182,7 +208,7 @@ load("@io_bazel_rules_go//go:deps.bzl", "go_register_toolchains", "go_rules_depe
 go_rules_dependencies()
 
 go_register_toolchains(
-    go_version = "1.22.4",
+    go_version = "1.24.6",
     nogo = "@//:nogo",
 )
 
@@ -227,56 +253,18 @@ filegroup(
     url = "https://github.com/ethereum/EIPs/archive/5480440fe51742ed23342b68cf106cefd427e39d.tar.gz",
 )
 
-consensus_spec_version = "v1.5.0-alpha.5"
+consensus_spec_version = "v1.6.0-alpha.1"
 
-bls_test_version = "v0.1.1"
+load("@prysm//tools:download_spectests.bzl", "consensus_spec_tests")
 
-http_archive(
-    name = "consensus_spec_tests_general",
-    build_file_content = """
-filegroup(
-    name = "test_data",
-    srcs = glob([
-        "**/*.ssz_snappy",
-        "**/*.yaml",
-    ]),
-    visibility = ["//visibility:public"],
-)
-    """,
-    integrity = "sha256-R9vG5HEL5eGMOAmbkKfJ2jfelNqL5V0xBUPiXOiGM6U=",
-    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/general.tar.gz" % consensus_spec_version,
-)
-
-http_archive(
-    name = "consensus_spec_tests_minimal",
-    build_file_content = """
-filegroup(
-    name = "test_data",
-    srcs = glob([
-        "**/*.ssz_snappy",
-        "**/*.yaml",
-    ]),
-    visibility = ["//visibility:public"],
-)
-    """,
-    integrity = "sha256-AEIiEOlf1XuxoRMCsN+kgJMo4LrS05+biTA1p/7Ro00=",
-    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/minimal.tar.gz" % consensus_spec_version,
-)
-
-http_archive(
-    name = "consensus_spec_tests_mainnet",
-    build_file_content = """
-filegroup(
-    name = "test_data",
-    srcs = glob([
-        "**/*.ssz_snappy",
-        "**/*.yaml",
-    ]),
-    visibility = ["//visibility:public"],
-)
-    """,
-    integrity = "sha256-LH/Xr20yrJRYnbpjRGupMWTIOWt3cpxZJWXgThwVDsk=",
-    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/mainnet.tar.gz" % consensus_spec_version,
+consensus_spec_tests(
+    name = "consensus_spec_tests",
+    flavors = {
+        "general": "sha256-o4t9p3R+fQHF4KOykGmwlG3zDw5wUdVWprkzId8aIsk=",
+        "minimal": "sha256-sU7ToI8t3MR8x0vVjC8ERmAHZDWpEmnAC9FWIpHi5x4=",
+        "mainnet": "sha256-YKS4wngg0LgI9Upp4MYJ77aG+8+e/G4YeqEIlp06LZw=",
+    },
+    version = consensus_spec_version,
 )
 
 http_archive(
@@ -290,11 +278,13 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    integrity = "sha256-mlytz4MPjKh0DwV7FMiAtnRbJw9B6o78/x66/vmnYc8=",
+    integrity = "sha256-Nv4TEuEJPQIM4E6T9J0FOITsmappmXZjGtlhe1HEXnU=",
     strip_prefix = "consensus-specs-" + consensus_spec_version[1:],
     url = "https://github.com/ethereum/consensus-specs/archive/refs/tags/%s.tar.gz" % consensus_spec_version,
 )
 
+bls_test_version = "v0.1.1"
+
 http_archive(
     name = "bls_spec_tests",
     build_file_content = """
@@ -337,9 +327,57 @@ filegroup(
     visibility = ["//visibility:public"],
 )
 """,
-    integrity = "sha256-b7ZTT+olF+VXEJYNTV5jggNtCkt9dOejm1i2VE+zy+0=",
-    strip_prefix = "holesky-874c199423ccd180607320c38cbaca05d9a1573a",
-    url = "https://github.com/eth-clients/holesky/archive/874c199423ccd180607320c38cbaca05d9a1573a.tar.gz",  # 2024-06-18
+    integrity = "sha256-YVFFrCmjoGZ3fXMWpsCpSsYbANy1grnqYwOLKIg2SsA=",
+    strip_prefix = "holesky-32a72e21c6e53c262f27d50dd540cb654517d03a",
+    url = "https://github.com/eth-clients/holesky/archive/32a72e21c6e53c262f27d50dd540cb654517d03a.tar.gz",  # 2025-03-17
+)
+
+http_archive(
+    name = "mainnet",
+    build_file_content = """
+filegroup(
+    name = "configs",
+    srcs = [
+        "metadata/config.yaml",
+    ],
+    visibility = ["//visibility:public"],
+)
+""",
+    integrity = "sha256-NZr/gsQK9rBHRnznlPBiNzJpK8MPMrfUa3f+QYqn1+g=",
+    strip_prefix = "mainnet-978f1794eada6f85bee76e4d2d5959a5fb8e0cc5",
+    url = "https://github.com/eth-clients/mainnet/archive/978f1794eada6f85bee76e4d2d5959a5fb8e0cc5.tar.gz",
+)
+
+http_archive(
+    name = "sepolia_testnet",
+    build_file_content = """
+filegroup(
+    name = "configs",
+    srcs = [
+        "metadata/config.yaml",
+    ],
+    visibility = ["//visibility:public"],
+)
+""",
+    integrity = "sha256-b5F7Wg9LLMqGRIpP2uqb/YsSFVn2ynzlV7g/Nb1EFLk=",
+    strip_prefix = "sepolia-562d9938f08675e9ba490a1dfba21fb05843f39f",
+    url = "https://github.com/eth-clients/sepolia/archive/562d9938f08675e9ba490a1dfba21fb05843f39f.tar.gz",  # 2025-03-17
+)
+
+http_archive(
+    name = "hoodi_testnet",
+    build_file_content = """
+filegroup(
+    name = "configs",
+    srcs = [
+        "metadata/config.yaml",
+    ],
+    visibility = ["//visibility:public"],
+)
+""",
+    integrity = "sha256-dPiEWUd8QvbYGwGtIm0QtCekitVLOLsW5rpQIGzz8PU=",
+    strip_prefix = "hoodi-828c2c940e1141092bd4bb979cef547ea926d272",
+    url = "https://github.com/eth-clients/hoodi/archive/828c2c940e1141092bd4bb979cef547ea926d272.tar.gz",
 )
 
 http_archive(
@@ -387,7 +425,7 @@ gometalinter_dependencies()
 
 load("@bazel_gazelle//:deps.bzl", "gazelle_dependencies")
 
-gazelle_dependencies()
+gazelle_dependencies(go_sdk = "go_sdk")
 
 load("@com_google_protobuf//:protobuf_deps.bzl", "protobuf_deps")
 

api/BUILD.bazel

@@ -7,7 +7,7 @@ go_library(
         "headers.go",
         "jwt.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api",
+    importpath = "github.com/OffchainLabs/prysm/v6/api",
     visibility = ["//visibility:public"],
     deps = [
         "//crypto/rand:go_default_library",

api/apiutil/BUILD.bazel

@@ -0,0 +1,29 @@
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "common.go",
+        "header.go",
+    ],
+    importpath = "github.com/OffchainLabs/prysm/v6/api/apiutil",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//consensus-types/primitives:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = [
+        "common_test.go",
+        "header_test.go",
+    ],
+    embed = [":go_default_library"],
+    deps = [
+        "//consensus-types/primitives:go_default_library",
+        "//testing/assert:go_default_library",
+        "//testing/require:go_default_library",
+    ],
+)

api/apiutil/common.go

@@ -0,0 +1,23 @@
+package apiutil
+
+import (
+	"fmt"
+	neturl "net/url"
+	"strconv"
+
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+)
+
+// Uint64ToString is a util function that will convert uints to string
+func Uint64ToString[T uint64 | primitives.Slot | primitives.ValidatorIndex | primitives.CommitteeIndex | primitives.Epoch](val T) string {
+	return strconv.FormatUint(uint64(val), 10)
+}
+
+// BuildURL is a util function that assists with adding query parameters to the url
+func BuildURL(path string, queryParams ...neturl.Values) string {
+	if len(queryParams) == 0 {
+		return path
+	}
+
+	return fmt.Sprintf("%s?%s", path, queryParams[0].Encode())
+}

api/apiutil/common_test.go

@@ -0,0 +1,37 @@
+package apiutil
+
+import (
+	"net/url"
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+)
+
+func TestBeaconApiHelpers_TestUint64ToString(t *testing.T) {
+	const expectedResult = "1234"
+	const val = uint64(1234)
+
+	assert.Equal(t, expectedResult, Uint64ToString(val))
+	assert.Equal(t, expectedResult, Uint64ToString(primitives.Slot(val)))
+	assert.Equal(t, expectedResult, Uint64ToString(primitives.ValidatorIndex(val)))
+	assert.Equal(t, expectedResult, Uint64ToString(primitives.CommitteeIndex(val)))
+	assert.Equal(t, expectedResult, Uint64ToString(primitives.Epoch(val)))
+}
+
+func TestBuildURL_NoParams(t *testing.T) {
+	wanted := "/aaa/bbb/ccc"
+	actual := BuildURL("/aaa/bbb/ccc")
+	assert.Equal(t, wanted, actual)
+}
+
+func TestBuildURL_WithParams(t *testing.T) {
+	params := url.Values{}
+	params.Add("xxxx", "1")
+	params.Add("yyyy", "2")
+	params.Add("zzzz", "3")
+
+	wanted := "/aaa/bbb/ccc?xxxx=1&yyyy=2&zzzz=3"
+	actual := BuildURL("/aaa/bbb/ccc", params)
+	assert.Equal(t, wanted, actual)
+}

api/apiutil/header.go

@@ -0,0 +1,122 @@
+package apiutil
+
+import (
+	"mime"
+	"sort"
+	"strconv"
+	"strings"
+
+	log "github.com/sirupsen/logrus"
+)
+
+type mediaRange struct {
+	mt   string  // canonicalised media‑type, e.g. "application/json"
+	q    float64 // quality factor (0‑1)
+	raw  string  // original string – useful for logging/debugging
+	spec int     // 2=exact, 1=type/*, 0=*/*
+}
+
+func parseMediaRange(field string) (mediaRange, bool) {
+	field = strings.TrimSpace(field)
+
+	mt, params, err := mime.ParseMediaType(field)
+	if err != nil {
+		log.WithError(err).Debug("Failed to parse header field")
+		return mediaRange{}, false
+	}
+
+	r := mediaRange{mt: mt, q: 1, spec: 2, raw: field}
+
+	if qs, ok := params["q"]; ok {
+		v, err := strconv.ParseFloat(qs, 64)
+		if err != nil || v < 0 || v > 1 {
+			log.WithField("q", qs).Debug("Invalid quality factor (0‑1)")
+			return mediaRange{}, false // skip invalid entry
+		}
+		r.q = v
+	}
+
+	switch {
+	case mt == "*/*":
+		r.spec = 0
+	case strings.HasSuffix(mt, "/*"):
+		r.spec = 1
+	}
+	return r, true
+}
+
+func hasExplicitQ(r mediaRange) bool {
+	return strings.Contains(strings.ToLower(r.raw), ";q=")
+}
+
+// ParseAccept returns media ranges sorted by q (desc) then specificity.
+func ParseAccept(header string) []mediaRange {
+	if header == "" {
+		return []mediaRange{{mt: "*/*", q: 1, spec: 0, raw: "*/*"}}
+	}
+
+	var out []mediaRange
+	for _, field := range strings.Split(header, ",") {
+		if r, ok := parseMediaRange(field); ok {
+			out = append(out, r)
+		}
+	}
+
+	sort.SliceStable(out, func(i, j int) bool {
+		ei, ej := hasExplicitQ(out[i]), hasExplicitQ(out[j])
+		if ei != ej {
+			return ei // explicit beats implicit
+		}
+		if out[i].q != out[j].q {
+			return out[i].q > out[j].q
+		}
+		return out[i].spec > out[j].spec
+	})
+	return out
+}
+
+// Matches reports whether content type is acceptable per the header.
+func Matches(header, ct string) bool {
+	for _, r := range ParseAccept(header) {
+		switch {
+		case r.q == 0:
+			continue
+		case r.mt == "*/*":
+			return true
+		case strings.HasSuffix(r.mt, "/*"):
+			if strings.HasPrefix(ct, r.mt[:len(r.mt)-1]) {
+				return true
+			}
+		case r.mt == ct:
+			return true
+		}
+	}
+	return false
+}
+
+// Negotiate selects the best server type according to the header.
+// Returns the chosen type and true, or "", false when nothing matches.
+func Negotiate(header string, serverTypes []string) (string, bool) {
+	for _, r := range ParseAccept(header) {
+		if r.q == 0 {
+			continue
+		}
+		for _, s := range serverTypes {
+			if Matches(r.mt, s) {
+				return s, true
+			}
+		}
+	}
+	return "", false
+}
+
+// PrimaryAcceptMatches only checks if the first accept matches
+func PrimaryAcceptMatches(header, produced string) bool {
+	for _, r := range ParseAccept(header) {
+		if r.q == 0 {
+			continue // explicitly unacceptable – skip
+		}
+		return Matches(r.mt, produced)
+	}
+	return false
+}

api/apiutil/header_test.go

@@ -0,0 +1,174 @@
+package apiutil
+
+import (
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+)
+
+func TestParseAccept(t *testing.T) {
+	type want struct {
+		mt   string
+		q    float64
+		spec int
+	}
+
+	cases := []struct {
+		name   string
+		header string
+		want   []want
+	}{
+		{
+			name:   "empty header becomes */*;q=1",
+			header: "",
+			want:   []want{{mt: "*/*", q: 1, spec: 0}},
+		},
+		{
+			name:   "quality ordering then specificity",
+			header: "application/json;q=0.2, */*;q=0.1, application/xml;q=0.5, text/*;q=0.5",
+			want: []want{
+				{mt: "application/xml", q: 0.5, spec: 2},
+				{mt: "text/*", q: 0.5, spec: 1},
+				{mt: "application/json", q: 0.2, spec: 2},
+				{mt: "*/*", q: 0.1, spec: 0},
+			},
+		},
+		{
+			name:   "invalid pieces are skipped",
+			header: "text/plain; q=boom, application/json",
+			want:   []want{{mt: "application/json", q: 1, spec: 2}},
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			got := ParseAccept(tc.header)
+			gotProjected := make([]want, len(got))
+			for i, g := range got {
+				gotProjected[i] = want{mt: g.mt, q: g.q, spec: g.spec}
+			}
+			require.DeepEqual(t, gotProjected, tc.want)
+		})
+	}
+}
+
+func TestMatches(t *testing.T) {
+	cases := []struct {
+		name    string
+		accept  string
+		ct      string
+		matches bool
+	}{
+		{"exact match", "application/json", "application/json", true},
+		{"type wildcard", "application/*;q=0.8", "application/xml", true},
+		{"global wildcard", "*/*;q=0.1", "image/png", true},
+		{"explicitly unacceptable (q=0)", "text/*;q=0", "text/plain", false},
+		{"no match", "image/png", "application/json", false},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			got := Matches(tc.accept, tc.ct)
+			require.Equal(t, tc.matches, got)
+		})
+	}
+}
+
+func TestNegotiate(t *testing.T) {
+	cases := []struct {
+		name        string
+		accept      string
+		serverTypes []string
+		wantType    string
+		ok          bool
+	}{
+		{
+			name:        "highest quality wins",
+			accept:      "application/json;q=0.8,application/xml;q=0.9",
+			serverTypes: []string{"application/json", "application/xml"},
+			wantType:    "application/xml",
+			ok:          true,
+		},
+		{
+			name:        "wildcard matches first server type",
+			accept:      "*/*;q=0.5",
+			serverTypes: []string{"application/octet-stream", "application/json"},
+			wantType:    "application/octet-stream",
+			ok:          true,
+		},
+		{
+			name:        "no acceptable type",
+			accept:      "image/png",
+			serverTypes: []string{"application/json"},
+			wantType:    "",
+			ok:          false,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			got, ok := Negotiate(tc.accept, tc.serverTypes)
+			require.Equal(t, tc.ok, ok)
+			require.Equal(t, tc.wantType, got)
+		})
+	}
+}
+
+func TestPrimaryAcceptMatches(t *testing.T) {
+	tests := []struct {
+		name     string
+		accept   string
+		produced string
+		expect   bool
+	}{
+		{
+			name:     "prefers json",
+			accept:   "application/json;q=0.9,application/xml",
+			produced: "application/json",
+			expect:   true,
+		},
+		{
+			name:     "wildcard application beats other wildcard",
+			accept:   "application/*;q=0.2,*/*;q=0.1",
+			produced: "application/xml",
+			expect:   true,
+		},
+		{
+			name:     "json wins",
+			accept:   "application/xml;q=0.8,application/json;q=0.9",
+			produced: "application/json",
+			expect:   true,
+		},
+		{
+			name:     "json loses",
+			accept:   "application/xml;q=0.8,application/json;q=0.9,application/octet-stream;q=0.99",
+			produced: "application/json",
+			expect:   false,
+		},
+		{
+			name:     "json wins with non q option",
+			accept:   "application/xml;q=0.8,image/png,application/json;q=0.9",
+			produced: "application/json",
+			expect:   true,
+		},
+		{
+			name:     "json not primary",
+			accept:   "image/png,application/json",
+			produced: "application/json",
+			expect:   false,
+		},
+		{
+			name:     "absent header",
+			accept:   "",
+			produced: "text/plain",
+			expect:   true,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			got := PrimaryAcceptMatches(tc.accept, tc.produced)
+			require.Equal(t, got, tc.expect)
+		})
+	}
+}

api/client/BUILD.bazel

@@ -7,7 +7,7 @@ go_library(
         "errors.go",
         "options.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/client",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/client",
     visibility = ["//visibility:public"],
     deps = ["@com_github_pkg_errors//:go_default_library"],
 )

api/client/beacon/BUILD.bazel

@@ -3,61 +3,32 @@ load("@prysm//tools/go:def.bzl", "go_library", "go_test")
 go_library(
     name = "go_default_library",
     srcs = [
-        "checkpoint.go",
         "client.go",
         "doc.go",
-        "health.go",
         "log.go",
+        "template.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/beacon",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/client/beacon",
     visibility = ["//visibility:public"],
     deps = [
         "//api/client:go_default_library",
-        "//api/client/beacon/iface:go_default_library",
         "//api/server:go_default_library",
         "//api/server/structs:go_default_library",
-        "//beacon-chain/core/helpers:go_default_library",
-        "//beacon-chain/state:go_default_library",
-        "//consensus-types/interfaces:go_default_library",
         "//consensus-types/primitives:go_default_library",
         "//encoding/bytesutil:go_default_library",
-        "//encoding/ssz/detect:go_default_library",
-        "//io/file:go_default_library",
-        "//network/forks:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
-        "//runtime/version:go_default_library",
-        "//time/slots:go_default_library",
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
-        "@org_golang_x_mod//semver:go_default_library",
     ],
 )
 
 go_test(
     name = "go_default_test",
-    srcs = [
-        "checkpoint_test.go",
-        "client_test.go",
-        "health_test.go",
-    ],
+    srcs = ["client_test.go"],
     embed = [":go_default_library"],
     deps = [
         "//api/client:go_default_library",
-        "//api/client/beacon/testing:go_default_library",
-        "//beacon-chain/state:go_default_library",
-        "//config/params:go_default_library",
-        "//consensus-types/blocks:go_default_library",
-        "//consensus-types/blocks/testing:go_default_library",
-        "//consensus-types/primitives:go_default_library",
-        "//encoding/ssz/detect:go_default_library",
-        "//network/forks:go_default_library",
-        "//proto/prysm/v1alpha1:go_default_library",
-        "//runtime/version:go_default_library",
         "//testing/require:go_default_library",
-        "//testing/util:go_default_library",
-        "//time/slots:go_default_library",
-        "@com_github_pkg_errors//:go_default_library",
-        "@org_uber_go_mock//gomock:go_default_library",
     ],
 )

api/client/beacon/checkpoint.go

@@ -1,276 +0,0 @@
-package beacon
-
-import (
-	"context"
-	"fmt"
-	"path"
-
-	"github.com/ethereum/go-ethereum/common/hexutil"
-	"github.com/pkg/errors"
-	base "github.com/prysmaticlabs/prysm/v5/api/client"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	"github.com/prysmaticlabs/prysm/v5/encoding/ssz/detect"
-	"github.com/prysmaticlabs/prysm/v5/io/file"
-	"github.com/prysmaticlabs/prysm/v5/runtime/version"
-	"github.com/prysmaticlabs/prysm/v5/time/slots"
-	"github.com/sirupsen/logrus"
-	"golang.org/x/mod/semver"
-)
-
-var errCheckpointBlockMismatch = errors.New("mismatch between checkpoint sync state and block")
-
-// OriginData represents the BeaconState and ReadOnlySignedBeaconBlock necessary to start an empty Beacon Node
-// using Checkpoint Sync.
-type OriginData struct {
-	sb []byte
-	bb []byte
-	st state.BeaconState
-	b  interfaces.ReadOnlySignedBeaconBlock
-	vu *detect.VersionedUnmarshaler
-	br [32]byte
-	sr [32]byte
-}
-
-// SaveBlock saves the downloaded block to a unique file in the given path.
-// For readability and collision avoidance, the file name includes: type, config name, slot and root
-func (o *OriginData) SaveBlock(dir string) (string, error) {
-	blockPath := path.Join(dir, fname("block", o.vu, o.b.Block().Slot(), o.br))
-	return blockPath, file.WriteFile(blockPath, o.BlockBytes())
-}
-
-// SaveState saves the downloaded state to a unique file in the given path.
-// For readability and collision avoidance, the file name includes: type, config name, slot and root
-func (o *OriginData) SaveState(dir string) (string, error) {
-	statePath := path.Join(dir, fname("state", o.vu, o.st.Slot(), o.sr))
-	return statePath, file.WriteFile(statePath, o.StateBytes())
-}
-
-// StateBytes returns the ssz-encoded bytes of the downloaded BeaconState value.
-func (o *OriginData) StateBytes() []byte {
-	return o.sb
-}
-
-// BlockBytes returns the ssz-encoded bytes of the downloaded ReadOnlySignedBeaconBlock value.
-func (o *OriginData) BlockBytes() []byte {
-	return o.bb
-}
-
-func fname(prefix string, vu *detect.VersionedUnmarshaler, slot primitives.Slot, root [32]byte) string {
-	return fmt.Sprintf("%s_%s_%s_%d-%#x.ssz", prefix, vu.Config.ConfigName, version.String(vu.Fork), slot, root)
-}
-
-// DownloadFinalizedData downloads the most recently finalized state, and the block most recently applied to that state.
-// This pair can be used to initialize a new beacon node via checkpoint sync.
-func DownloadFinalizedData(ctx context.Context, client *Client) (*OriginData, error) {
-	sb, err := client.GetState(ctx, IdFinalized)
-	if err != nil {
-		return nil, err
-	}
-	vu, err := detect.FromState(sb)
-	if err != nil {
-		return nil, errors.Wrap(err, "error detecting chain config for finalized state")
-	}
-
-	log.WithFields(logrus.Fields{
-		"name": vu.Config.ConfigName,
-		"fork": version.String(vu.Fork),
-	}).Info("Detected supported config in remote finalized state")
-
-	s, err := vu.UnmarshalBeaconState(sb)
-	if err != nil {
-		return nil, errors.Wrap(err, "error unmarshaling finalized state to correct version")
-	}
-
-	slot := s.LatestBlockHeader().Slot
-	bb, err := client.GetBlock(ctx, IdFromSlot(slot))
-	if err != nil {
-		return nil, errors.Wrapf(err, "error requesting block by slot = %d", slot)
-	}
-	b, err := vu.UnmarshalBeaconBlock(bb)
-	if err != nil {
-		return nil, errors.Wrap(err, "unable to unmarshal block to a supported type using the detected fork schedule")
-	}
-	br, err := b.Block().HashTreeRoot()
-	if err != nil {
-		return nil, errors.Wrap(err, "error computing hash_tree_root of retrieved block")
-	}
-	bodyRoot, err := b.Block().Body().HashTreeRoot()
-	if err != nil {
-		return nil, errors.Wrap(err, "error computing hash_tree_root of retrieved block body")
-	}
-
-	sbr := bytesutil.ToBytes32(s.LatestBlockHeader().BodyRoot)
-	if sbr != bodyRoot {
-		return nil, errors.Wrapf(errCheckpointBlockMismatch, "state body root = %#x, block body root = %#x", sbr, bodyRoot)
-	}
-	sr, err := s.HashTreeRoot(ctx)
-	if err != nil {
-		return nil, errors.Wrapf(err, "failed to compute htr for finalized state at slot=%d", s.Slot())
-	}
-
-	log.
-		WithField("blockSlot", b.Block().Slot()).
-		WithField("stateSlot", s.Slot()).
-		WithField("stateRoot", hexutil.Encode(sr[:])).
-		WithField("blockRoot", hexutil.Encode(br[:])).
-		Info("Downloaded checkpoint sync state and block.")
-	return &OriginData{
-		st: s,
-		b:  b,
-		sb: sb,
-		bb: bb,
-		vu: vu,
-		br: br,
-		sr: sr,
-	}, nil
-}
-
-// WeakSubjectivityData represents the state root, block root and epoch of the BeaconState + ReadOnlySignedBeaconBlock
-// that falls at the beginning of the current weak subjectivity period. These values can be used to construct
-// a weak subjectivity checkpoint beacon node flag to be used for validation.
-type WeakSubjectivityData struct {
-	BlockRoot [32]byte
-	StateRoot [32]byte
-	Epoch     primitives.Epoch
-}
-
-// CheckpointString returns the standard string representation of a Checkpoint.
-// The format is a hex-encoded block root, followed by the epoch of the block, separated by a colon. For example:
-// "0x1c35540cac127315fabb6bf29181f2ae0de1a3fc909d2e76ba771e61312cc49a:74888"
-func (wsd *WeakSubjectivityData) CheckpointString() string {
-	return fmt.Sprintf("%#x:%d", wsd.BlockRoot, wsd.Epoch)
-}
-
-// ComputeWeakSubjectivityCheckpoint attempts to use the prysm weak_subjectivity api
-// to obtain the current weak_subjectivity checkpoint.
-// For non-prysm nodes, the same computation will be performed with extra steps,
-// using the head state downloaded from the beacon node api.
-func ComputeWeakSubjectivityCheckpoint(ctx context.Context, client *Client) (*WeakSubjectivityData, error) {
-	ws, err := client.GetWeakSubjectivity(ctx)
-	if err != nil {
-		// a 404/405 is expected if querying an endpoint that doesn't support the weak subjectivity checkpoint api
-		if !errors.Is(err, base.ErrNotOK) {
-			return nil, errors.Wrap(err, "unexpected API response for prysm-only weak subjectivity checkpoint API")
-		}
-		// fall back to vanilla Beacon Node API method
-		return computeBackwardsCompatible(ctx, client)
-	}
-	log.Printf("server weak subjectivity checkpoint response - epoch=%d, block_root=%#x, state_root=%#x", ws.Epoch, ws.BlockRoot, ws.StateRoot)
-	return ws, nil
-}
-
-const (
-	prysmMinimumVersion     = "v2.0.7"
-	prysmImplementationName = "Prysm"
-)
-
-// errUnsupportedPrysmCheckpointVersion indicates remote beacon node can't be used for checkpoint retrieval.
-var errUnsupportedPrysmCheckpointVersion = errors.New("node does not meet minimum version requirements for checkpoint retrieval")
-
-// for older endpoints or clients that do not support the weak_subjectivity api method
-// we gather the necessary data for a checkpoint sync by:
-// - inspecting the remote server's head state and computing the weak subjectivity epoch locally
-// - requesting the state at the first slot of the epoch
-// - using hash_tree_root(state.latest_block_header) to compute the block the state integrates
-// - requesting that block by its root
-func computeBackwardsCompatible(ctx context.Context, client *Client) (*WeakSubjectivityData, error) {
-	log.Print("falling back to generic checkpoint derivation, weak_subjectivity API not supported by server")
-	nv, err := client.GetNodeVersion(ctx)
-	if err != nil {
-		return nil, errors.Wrap(err, "unable to proceed with fallback method without confirming node version")
-	}
-	if nv.implementation == prysmImplementationName && semver.Compare(nv.semver, prysmMinimumVersion) < 0 {
-		return nil, errors.Wrapf(errUnsupportedPrysmCheckpointVersion, "%s < minimum (%s)", nv.semver, prysmMinimumVersion)
-	}
-	epoch, err := getWeakSubjectivityEpochFromHead(ctx, client)
-	if err != nil {
-		return nil, errors.Wrap(err, "error computing weak subjectivity epoch via head state inspection")
-	}
-
-	// use first slot of the epoch for the state slot
-	slot, err := slots.EpochStart(epoch)
-	if err != nil {
-		return nil, errors.Wrapf(err, "error computing first slot of epoch=%d", epoch)
-	}
-
-	log.Printf("requesting checkpoint state at slot %d", slot)
-	// get the state at the first slot of the epoch
-	sb, err := client.GetState(ctx, IdFromSlot(slot))
-	if err != nil {
-		return nil, errors.Wrapf(err, "failed to request state by slot from api, slot=%d", slot)
-	}
-
-	// ConfigFork is used to unmarshal the BeaconState so we can read the block root in latest_block_header
-	vu, err := detect.FromState(sb)
-	if err != nil {
-		return nil, errors.Wrap(err, "error detecting chain config for beacon state")
-	}
-	log.Printf("detected supported config in checkpoint state, name=%s, fork=%s", vu.Config.ConfigName, version.String(vu.Fork))
-
-	s, err := vu.UnmarshalBeaconState(sb)
-	if err != nil {
-		return nil, errors.Wrap(err, "error using detected config fork to unmarshal state bytes")
-	}
-
-	// compute state and block roots
-	sr, err := s.HashTreeRoot(ctx)
-	if err != nil {
-		return nil, errors.Wrap(err, "error computing hash_tree_root of state")
-	}
-
-	h := s.LatestBlockHeader()
-	h.StateRoot = sr[:]
-	br, err := h.HashTreeRoot()
-	if err != nil {
-		return nil, errors.Wrap(err, "error while computing block root using state data")
-	}
-
-	bb, err := client.GetBlock(ctx, IdFromRoot(br))
-	if err != nil {
-		return nil, errors.Wrapf(err, "error requesting block by root = %d", br)
-	}
-	b, err := vu.UnmarshalBeaconBlock(bb)
-	if err != nil {
-		return nil, errors.Wrap(err, "unable to unmarshal block to a supported type using the detected fork schedule")
-	}
-	br, err = b.Block().HashTreeRoot()
-	if err != nil {
-		return nil, errors.Wrap(err, "error computing hash_tree_root for block obtained via root")
-	}
-
-	return &WeakSubjectivityData{
-		Epoch:     epoch,
-		BlockRoot: br,
-		StateRoot: sr,
-	}, nil
-}
-
-// this method downloads the head state, which can be used to find the correct chain config
-// and use prysm's helper methods to compute the latest weak subjectivity epoch.
-func getWeakSubjectivityEpochFromHead(ctx context.Context, client *Client) (primitives.Epoch, error) {
-	headBytes, err := client.GetState(ctx, IdHead)
-	if err != nil {
-		return 0, err
-	}
-	vu, err := detect.FromState(headBytes)
-	if err != nil {
-		return 0, errors.Wrap(err, "error detecting chain config for beacon state")
-	}
-	log.Printf("detected supported config in remote head state, name=%s, fork=%s", vu.Config.ConfigName, version.String(vu.Fork))
-	headState, err := vu.UnmarshalBeaconState(headBytes)
-	if err != nil {
-		return 0, errors.Wrap(err, "error unmarshaling state to correct version")
-	}
-
-	epoch, err := helpers.LatestWeakSubjectivityEpoch(ctx, headState, vu.Config)
-	if err != nil {
-		return 0, errors.Wrap(err, "error computing the weak subjectivity epoch from head state")
-	}
-
-	log.Printf("(computed client-side) weak subjectivity epoch = %d", epoch)
-	return epoch, nil
-}

api/client/beacon/client.go

@@ -9,19 +9,16 @@ import (
 	"net/url"
 	"path"
 	"regexp"
-	"sort"
 	"strconv"
-	"text/template"
 
+	"github.com/OffchainLabs/prysm/v6/api/client"
+	"github.com/OffchainLabs/prysm/v6/api/server"
+	"github.com/OffchainLabs/prysm/v6/api/server/structs"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/api/client"
-	"github.com/prysmaticlabs/prysm/v5/api/server"
-	"github.com/prysmaticlabs/prysm/v5/api/server/structs"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	"github.com/prysmaticlabs/prysm/v5/network/forks"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/sirupsen/logrus"
 )
 
@@ -29,12 +26,13 @@ const (
 	getSignedBlockPath       = "/eth/v2/beacon/blocks"
 	getBlockRootPath         = "/eth/v1/beacon/blocks/{{.Id}}/root"
 	getForkForStatePath      = "/eth/v1/beacon/states/{{.Id}}/fork"
-	getWeakSubjectivityPath  = "/prysm/v1/beacon/weak_subjectivity"
 	getForkSchedulePath      = "/eth/v1/config/fork_schedule"
 	getConfigSpecPath        = "/eth/v1/config/spec"
 	getStatePath             = "/eth/v2/debug/beacon/states"
-	getNodeVersionPath       = "/eth/v1/node/version"
 	changeBLStoExecutionPath = "/eth/v1/beacon/pool/bls_to_execution_changes"
+
+	GetNodeVersionPath      = "/eth/v1/node/version"
+	GetWeakSubjectivityPath = "/prysm/v1/beacon/weak_subjectivity"
 )
 
 // StateOrBlockId represents the block_id / state_id parameters that several of the Eth Beacon API methods accept.
@@ -63,24 +61,8 @@ func IdFromSlot(s primitives.Slot) StateOrBlockId {
 	return StateOrBlockId(strconv.FormatUint(uint64(s), 10))
 }
 
-// idTemplate is used to create template functions that can interpolate StateOrBlockId values.
-func idTemplate(ts string) func(StateOrBlockId) string {
-	t := template.Must(template.New("").Parse(ts))
-	f := func(id StateOrBlockId) string {
-		b := bytes.NewBuffer(nil)
-		err := t.Execute(b, struct{ Id string }{Id: string(id)})
-		if err != nil {
-			panic(fmt.Sprintf("invalid idTemplate: %s", ts))
-		}
-		return b.String()
-	}
-	// run the template to ensure that it is valid
-	// this should happen load time (using package scoped vars) to ensure runtime errors aren't possible
-	_ = f(IdGenesis)
-	return f
-}
-
-func renderGetBlockPath(id StateOrBlockId) string {
+// RenderGetBlockPath formats a block id into a path for the GetBlock API endpoint.
+func RenderGetBlockPath(id StateOrBlockId) string {
 	return path.Join(getSignedBlockPath, string(id))
 }
 
@@ -104,7 +86,7 @@ func NewClient(host string, opts ...client.ClientOpt) (*Client, error) {
 // for the named identifiers.
 // The return value contains the ssz-encoded bytes.
 func (c *Client) GetBlock(ctx context.Context, blockId StateOrBlockId) ([]byte, error) {
-	blockPath := renderGetBlockPath(blockId)
+	blockPath := RenderGetBlockPath(blockId)
 	b, err := c.Get(ctx, blockPath, client.WithSSZEncoding())
 	if err != nil {
 		return nil, errors.Wrapf(err, "error requesting state by id = %s", blockId)
@@ -112,8 +94,6 @@ func (c *Client) GetBlock(ctx context.Context, blockId StateOrBlockId) ([]byte,
 	return b, nil
 }
 
-var getBlockRootTpl = idTemplate(getBlockRootPath)
-
 // GetBlockRoot retrieves the hash_tree_root of the BeaconBlock for the given block id.
 // Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
 // <slot>, <hex encoded blockRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
@@ -136,8 +116,6 @@ func (c *Client) GetBlockRoot(ctx context.Context, blockId StateOrBlockId) ([32]
 	return bytesutil.ToBytes32(rs), nil
 }
 
-var getForkTpl = idTemplate(getForkForStatePath)
-
 // GetFork queries the Beacon Node API for the Fork from the state identified by stateId.
 // Block identifier can be one of: "head" (canonical head in node's view), "genesis", "finalized",
 // <slot>, <hex encoded blockRoot with 0x prefix>. Variables of type StateOrBlockId are exported by this package
@@ -157,24 +135,6 @@ func (c *Client) GetFork(ctx context.Context, stateId StateOrBlockId) (*ethpb.Fo
 	return fr.ToConsensus()
 }
 
-// GetForkSchedule retrieve all forks, past present and future, of which this node is aware.
-func (c *Client) GetForkSchedule(ctx context.Context) (forks.OrderedSchedule, error) {
-	body, err := c.Get(ctx, getForkSchedulePath)
-	if err != nil {
-		return nil, errors.Wrap(err, "error requesting fork schedule")
-	}
-	fsr := &forkScheduleResponse{}
-	err = json.Unmarshal(body, fsr)
-	if err != nil {
-		return nil, err
-	}
-	ofs, err := fsr.OrderedForkSchedule()
-	if err != nil {
-		return nil, errors.Wrap(err, fmt.Sprintf("problem unmarshaling %s response", getForkSchedulePath))
-	}
-	return ofs, nil
-}
-
 // GetConfigSpec retrieve the current configs of the network used by the beacon node.
 func (c *Client) GetConfigSpec(ctx context.Context) (*structs.GetSpecResponse, error) {
 	body, err := c.Get(ctx, getConfigSpecPath)
@@ -195,6 +155,10 @@ type NodeVersion struct {
 	systemInfo     string
 }
 
+func (nv *NodeVersion) SetImplementation(impl string) {
+	nv.implementation = impl
+}
+
 var versionRE = regexp.MustCompile(`^(\w+)/(v\d+\.\d+\.\d+[-a-zA-Z0-9]*)\s*/?(.*)$`)
 
 func parseNodeVersion(v string) (*NodeVersion, error) {
@@ -212,7 +176,7 @@ func parseNodeVersion(v string) (*NodeVersion, error) {
 // GetNodeVersion requests that the beacon node identify information about its implementation in a format
 // similar to a HTTP User-Agent field. ex: Lighthouse/v0.1.5 (Linux x86_64)
 func (c *Client) GetNodeVersion(ctx context.Context) (*NodeVersion, error) {
-	b, err := c.Get(ctx, getNodeVersionPath)
+	b, err := c.Get(ctx, GetNodeVersionPath)
 	if err != nil {
 		return nil, errors.Wrap(err, "error requesting node version")
 	}
@@ -228,7 +192,8 @@ func (c *Client) GetNodeVersion(ctx context.Context) (*NodeVersion, error) {
 	return parseNodeVersion(d.Data.Version)
 }
 
-func renderGetStatePath(id StateOrBlockId) string {
+// RenderGetStatePath formats a state id into a path for the GetState API endpoint.
+func RenderGetStatePath(id StateOrBlockId) string {
 	return path.Join(getStatePath, string(id))
 }
 
@@ -246,13 +211,29 @@ func (c *Client) GetState(ctx context.Context, stateId StateOrBlockId) ([]byte,
 	return b, nil
 }
 
+// WeakSubjectivityData represents the state root, block root and epoch of the BeaconState + ReadOnlySignedBeaconBlock
+// that falls at the beginning of the current weak subjectivity period. These values can be used to construct
+// a weak subjectivity checkpoint beacon node flag to be used for validation.
+type WeakSubjectivityData struct {
+	BlockRoot [32]byte
+	StateRoot [32]byte
+	Epoch     primitives.Epoch
+}
+
+// CheckpointString returns the standard string representation of a Checkpoint.
+// The format is a hex-encoded block root, followed by the epoch of the block, separated by a colon. For example:
+// "0x1c35540cac127315fabb6bf29181f2ae0de1a3fc909d2e76ba771e61312cc49a:74888"
+func (wsd *WeakSubjectivityData) CheckpointString() string {
+	return fmt.Sprintf("%#x:%d", wsd.BlockRoot, wsd.Epoch)
+}
+
 // GetWeakSubjectivity calls a proposed API endpoint that is unique to prysm
 // This api method does the following:
 // - computes weak subjectivity epoch
 // - finds the highest non-skipped block preceding the epoch
 // - returns the htr of the found block and returns this + the value of state_root from the block
 func (c *Client) GetWeakSubjectivity(ctx context.Context) (*WeakSubjectivityData, error) {
-	body, err := c.Get(ctx, getWeakSubjectivityPath)
+	body, err := c.Get(ctx, GetWeakSubjectivityPath)
 	if err != nil {
 		return nil, err
 	}
@@ -333,31 +314,3 @@ func (c *Client) GetBLStoExecutionChanges(ctx context.Context) (*structs.BLSToEx
 	}
 	return poolResponse, nil
 }
-
-type forkScheduleResponse struct {
-	Data []structs.Fork
-}
-
-func (fsr *forkScheduleResponse) OrderedForkSchedule() (forks.OrderedSchedule, error) {
-	ofs := make(forks.OrderedSchedule, 0)
-	for _, d := range fsr.Data {
-		epoch, err := strconv.ParseUint(d.Epoch, 10, 64)
-		if err != nil {
-			return nil, errors.Wrapf(err, "error parsing epoch %s", d.Epoch)
-		}
-		vSlice, err := hexutil.Decode(d.CurrentVersion)
-		if err != nil {
-			return nil, err
-		}
-		if len(vSlice) != 4 {
-			return nil, fmt.Errorf("got %d byte version, expected 4 bytes. version hex=%s", len(vSlice), d.CurrentVersion)
-		}
-		version := bytesutil.ToBytes4(vSlice)
-		ofs = append(ofs, forks.ForkScheduleEntry{
-			Version: version,
-			Epoch:   primitives.Epoch(epoch),
-		})
-	}
-	sort.Sort(ofs)
-	return ofs, nil
-}

api/client/beacon/client_test.go

@@ -4,8 +4,8 @@ import (
 	"net/url"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/api/client"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/api/client"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 )
 
 func TestParseNodeVersion(t *testing.T) {
@@ -97,31 +97,31 @@ func TestValidHostname(t *testing.T) {
 		{
 			name:    "hostname with port",
 			hostArg: "mydomain.org:3500",
-			path:    getNodeVersionPath,
+			path:    GetNodeVersionPath,
 			joined:  "http://mydomain.org:3500/eth/v1/node/version",
 		},
 		{
 			name:    "https scheme, hostname with port",
 			hostArg: "https://mydomain.org:3500",
-			path:    getNodeVersionPath,
+			path:    GetNodeVersionPath,
 			joined:  "https://mydomain.org:3500/eth/v1/node/version",
 		},
 		{
 			name:    "http scheme, hostname without port",
 			hostArg: "http://mydomain.org",
-			path:    getNodeVersionPath,
+			path:    GetNodeVersionPath,
 			joined:  "http://mydomain.org/eth/v1/node/version",
 		},
 		{
 			name:    "http scheme, trailing slash, hostname without port",
 			hostArg: "http://mydomain.org/",
-			path:    getNodeVersionPath,
+			path:    GetNodeVersionPath,
 			joined:  "http://mydomain.org/eth/v1/node/version",
 		},
 		{
 			name:    "http scheme, hostname with basic auth creds and no port",
 			hostArg: "http://username:pass@mydomain.org/",
-			path:    getNodeVersionPath,
+			path:    GetNodeVersionPath,
 			joined:  "http://username:pass@mydomain.org/eth/v1/node/version",
 		},
 	}

api/client/beacon/health.go

@@ -1,60 +0,0 @@
-package beacon
-
-import (
-	"context"
-	"sync"
-
-	"github.com/prysmaticlabs/prysm/v5/api/client/beacon/iface"
-)
-
-type NodeHealthTracker struct {
-	isHealthy  *bool
-	healthChan chan bool
-	node       iface.HealthNode
-	sync.RWMutex
-}
-
-func NewNodeHealthTracker(node iface.HealthNode) *NodeHealthTracker {
-	return &NodeHealthTracker{
-		node:       node,
-		healthChan: make(chan bool, 1),
-	}
-}
-
-// HealthUpdates provides a read-only channel for health updates.
-func (n *NodeHealthTracker) HealthUpdates() <-chan bool {
-	return n.healthChan
-}
-
-func (n *NodeHealthTracker) IsHealthy() bool {
-	n.RLock()
-	defer n.RUnlock()
-	if n.isHealthy == nil {
-		return false
-	}
-	return *n.isHealthy
-}
-
-func (n *NodeHealthTracker) CheckHealth(ctx context.Context) bool {
-	n.Lock()
-	defer n.Unlock()
-
-	newStatus := n.node.IsHealthy(ctx)
-	if n.isHealthy == nil {
-		n.isHealthy = &newStatus
-	}
-
-	isStatusChanged := newStatus != *n.isHealthy
-	if isStatusChanged {
-		// Update the health status
-		n.isHealthy = &newStatus
-		// Send the new status to the health channel, potentially overwriting the existing value
-		select {
-		case <-n.healthChan:
-			n.healthChan <- newStatus
-		default:
-			n.healthChan <- newStatus
-		}
-	}
-	return newStatus
-}

api/client/beacon/health_test.go

@@ -1,112 +0,0 @@
-package beacon
-
-import (
-	"context"
-	"sync"
-	"testing"
-
-	healthTesting "github.com/prysmaticlabs/prysm/v5/api/client/beacon/testing"
-	"go.uber.org/mock/gomock"
-)
-
-func TestNodeHealth_IsHealthy(t *testing.T) {
-	tests := []struct {
-		name      string
-		isHealthy bool
-		want      bool
-	}{
-		{"initially healthy", true, true},
-		{"initially unhealthy", false, false},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			n := &NodeHealthTracker{
-				isHealthy:  &tt.isHealthy,
-				healthChan: make(chan bool, 1),
-			}
-			if got := n.IsHealthy(); got != tt.want {
-				t.Errorf("IsHealthy() = %v, want %v", got, tt.want)
-			}
-		})
-	}
-}
-
-func TestNodeHealth_UpdateNodeHealth(t *testing.T) {
-	tests := []struct {
-		name       string
-		initial    bool // Initial health status
-		newStatus  bool // Status to update to
-		shouldSend bool // Should a message be sent through the channel
-	}{
-		{"healthy to unhealthy", true, false, true},
-		{"unhealthy to healthy", false, true, true},
-		{"remain healthy", true, true, false},
-		{"remain unhealthy", false, false, false},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			ctrl := gomock.NewController(t)
-			defer ctrl.Finish()
-			client := healthTesting.NewMockHealthClient(ctrl)
-			client.EXPECT().IsHealthy(gomock.Any()).Return(tt.newStatus)
-			n := &NodeHealthTracker{
-				isHealthy:  &tt.initial,
-				node:       client,
-				healthChan: make(chan bool, 1),
-			}
-
-			s := n.CheckHealth(context.Background())
-			// Check if health status was updated
-			if s != tt.newStatus {
-				t.Errorf("UpdateNodeHealth() failed to update isHealthy from %v to %v", tt.initial, tt.newStatus)
-			}
-
-			select {
-			case status := <-n.HealthUpdates():
-				if !tt.shouldSend {
-					t.Errorf("UpdateNodeHealth() unexpectedly sent status %v to HealthCh", status)
-				} else if status != tt.newStatus {
-					t.Errorf("UpdateNodeHealth() sent wrong status %v, want %v", status, tt.newStatus)
-				}
-			default:
-				if tt.shouldSend {
-					t.Error("UpdateNodeHealth() did not send any status to HealthCh when expected")
-				}
-			}
-		})
-	}
-}
-
-func TestNodeHealth_Concurrency(t *testing.T) {
-	ctrl := gomock.NewController(t)
-	defer ctrl.Finish()
-	client := healthTesting.NewMockHealthClient(ctrl)
-	n := NewNodeHealthTracker(client)
-	var wg sync.WaitGroup
-
-	// Number of goroutines to spawn for both reading and writing
-	numGoroutines := 6
-
-	wg.Add(numGoroutines * 2) // for readers and writers
-
-	// Concurrently update health status
-	for i := 0; i < numGoroutines; i++ {
-		go func() {
-			defer wg.Done()
-			client.EXPECT().IsHealthy(gomock.Any()).Return(false).Times(1)
-			n.CheckHealth(context.Background())
-			client.EXPECT().IsHealthy(gomock.Any()).Return(true).Times(1)
-			n.CheckHealth(context.Background())
-		}()
-	}
-
-	// Concurrently read health status
-	for i := 0; i < numGoroutines; i++ {
-		go func() {
-			defer wg.Done()
-			_ = n.IsHealthy() // Just read the value
-		}()
-	}
-
-	wg.Wait() // Wait for all goroutines to finish
-}

api/client/beacon/iface/health.go

@@ -1,13 +0,0 @@
-package iface
-
-import "context"
-
-type HealthTracker interface {
-	HealthUpdates() <-chan bool
-	IsHealthy() bool
-	CheckHealth(ctx context.Context) bool
-}
-
-type HealthNode interface {
-	IsHealthy(ctx context.Context) bool
-}

api/client/beacon/template.go

@@ -0,0 +1,34 @@
+package beacon
+
+import (
+	"bytes"
+	"fmt"
+	"text/template"
+)
+
+type templateFn func(StateOrBlockId) string
+
+var getBlockRootTpl templateFn
+var getForkTpl templateFn
+
+func init() {
+	// idTemplate is used to create template functions that can interpolate StateOrBlockId values.
+	idTemplate := func(ts string) func(StateOrBlockId) string {
+		t := template.Must(template.New("").Parse(ts))
+		f := func(id StateOrBlockId) string {
+			b := bytes.NewBuffer(nil)
+			err := t.Execute(b, struct{ Id string }{Id: string(id)})
+			if err != nil {
+				panic(fmt.Sprintf("invalid idTemplate: %s", ts))
+			}
+			return b.String()
+		}
+		// run the template to ensure that it is valid
+		// this should happen load time (using package scoped vars) to ensure runtime errors aren't possible
+		_ = f(IdGenesis)
+		return f
+	}
+
+	getBlockRootTpl = idTemplate(getBlockRootPath)
+	getForkTpl = idTemplate(getForkForStatePath)
+}

api/client/beacon/testing/BUILD.bazel

@@ -1,12 +0,0 @@
-load("@prysm//tools/go:def.bzl", "go_library")
-
-go_library(
-    name = "go_default_library",
-    srcs = ["mock.go"],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/beacon/testing",
-    visibility = ["//visibility:public"],
-    deps = [
-        "//api/client/beacon/iface:go_default_library",
-        "@org_uber_go_mock//gomock:go_default_library",
-    ],
-)

api/client/beacon/testing/mock.go

@@ -1,59 +0,0 @@
-package testing
-
-import (
-	"context"
-	"reflect"
-	"sync"
-
-	"github.com/prysmaticlabs/prysm/v5/api/client/beacon/iface"
-	"go.uber.org/mock/gomock"
-)
-
-var (
-	_ = iface.HealthNode(&MockHealthClient{})
-)
-
-// MockHealthClient is a mock of HealthClient interface.
-type MockHealthClient struct {
-	ctrl     *gomock.Controller
-	recorder *MockHealthClientMockRecorder
-	sync.Mutex
-}
-
-// MockHealthClientMockRecorder is the mock recorder for MockHealthClient.
-type MockHealthClientMockRecorder struct {
-	mock *MockHealthClient
-}
-
-// IsHealthy mocks base method.
-func (m *MockHealthClient) IsHealthy(arg0 context.Context) bool {
-	m.Lock()
-	defer m.Unlock()
-	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "IsHealthy", arg0)
-	ret0, ok := ret[0].(bool)
-	if !ok {
-		return false
-	}
-	return ret0
-}
-
-// EXPECT returns an object that allows the caller to indicate expected use.
-func (m *MockHealthClient) EXPECT() *MockHealthClientMockRecorder {
-	return m.recorder
-}
-
-// IsHealthy indicates an expected call of IsHealthy.
-func (mr *MockHealthClientMockRecorder) IsHealthy(arg0 any) *gomock.Call {
-	mr.mock.Lock()
-	defer mr.mock.Unlock()
-	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "IsHealthy", reflect.TypeOf((*MockHealthClient)(nil).IsHealthy), arg0)
-}
-
-// NewMockHealthClient creates a new mock instance.
-func NewMockHealthClient(ctrl *gomock.Controller) *MockHealthClient {
-	mock := &MockHealthClient{ctrl: ctrl}
-	mock.recorder = &MockHealthClientMockRecorder{mock}
-	return mock
-}

api/client/builder/BUILD.bazel

@@ -8,12 +8,14 @@ go_library(
         "errors.go",
         "types.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/builder",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/client/builder",
     visibility = ["//visibility:public"],
     deps = [
         "//api:go_default_library",
+        "//api/client:go_default_library",
         "//api/server/structs:go_default_library",
         "//config/fieldparams:go_default_library",
+        "//config/params:go_default_library",
         "//consensus-types:go_default_library",
         "//consensus-types/blocks:go_default_library",
         "//consensus-types/interfaces:go_default_library",
@@ -21,6 +23,7 @@ go_library(
         "//encoding/bytesutil:go_default_library",
         "//math:go_default_library",
         "//monitoring/tracing:go_default_library",
+        "//monitoring/tracing/trace:go_default_library",
         "//proto/engine/v1:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
         "//runtime/version:go_default_library",
@@ -28,7 +31,7 @@ go_library(
         "@com_github_pkg_errors//:go_default_library",
         "@com_github_prysmaticlabs_fastssz//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
-        "@io_opencensus_go//trace:go_default_library",
+        "@io_opentelemetry_go_contrib_instrumentation_net_http_otelhttp//:go_default_library",
         "@org_golang_google_protobuf//proto:go_default_library",
     ],
 )
@@ -42,10 +45,12 @@ go_test(
     data = glob(["testdata/**"]),
     embed = [":go_default_library"],
     deps = [
+        "//api:go_default_library",
         "//api/server/structs:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
         "//consensus-types/blocks:go_default_library",
+        "//consensus-types/interfaces:go_default_library",
         "//consensus-types/primitives:go_default_library",
         "//encoding/bytesutil:go_default_library",
         "//math:go_default_library",

api/client/builder/bid.go

@@ -1,14 +1,14 @@
 package builder
 
 import (
-	"github.com/pkg/errors"
+	consensus_types "github.com/OffchainLabs/prysm/v6/consensus-types"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	v1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	ssz "github.com/prysmaticlabs/fastssz"
-	consensus_types "github.com/prysmaticlabs/prysm/v5/consensus-types"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/runtime/version"
 )
 
 // SignedBid is an interface describing the method set of a signed builder bid.
@@ -22,7 +22,6 @@ type SignedBid interface {
 // Bid is an interface describing the method set of a builder bid.
 type Bid interface {
 	Header() (interfaces.ExecutionData, error)
-	BlobKzgCommitments() ([][]byte, error)
 	Value() primitives.Wei
 	Pubkey() []byte
 	Version() int
@@ -31,6 +30,18 @@ type Bid interface {
 	HashTreeRootWith(hh *ssz.Hasher) error
 }
 
+// BidDeneb is an interface that exposes newly added kzg commitments on top of builder bid
+type BidDeneb interface {
+	Bid
+	BlobKzgCommitments() [][]byte
+}
+
+// BidElectra is an interface that exposes the newly added execution requests on top of the builder bid
+type BidElectra interface {
+	BidDeneb
+	ExecutionRequests() *v1.ExecutionRequests
+}
+
 type signedBuilderBid struct {
 	p *ethpb.SignedBuilderBid
 }
@@ -115,11 +126,6 @@ func (b builderBid) Header() (interfaces.ExecutionData, error) {
 	return blocks.WrappedExecutionPayloadHeader(b.p.Header)
 }
 
-// BlobKzgCommitments --
-func (b builderBid) BlobKzgCommitments() ([][]byte, error) {
-	return [][]byte{}, errors.New("blob kzg commitments not available before Deneb")
-}
-
 // Version --
 func (b builderBid) Version() int {
 	return version.Bellatrix
@@ -169,11 +175,6 @@ func (b builderBidCapella) Header() (interfaces.ExecutionData, error) {
 	return blocks.WrappedExecutionPayloadHeaderCapella(b.p.Header)
 }
 
-// BlobKzgCommitments --
-func (b builderBidCapella) BlobKzgCommitments() ([][]byte, error) {
-	return [][]byte{}, errors.New("blob kzg commitments not available before Deneb")
-}
-
 // Version --
 func (b builderBidCapella) Version() int {
 	return version.Capella
@@ -254,8 +255,8 @@ func (b builderBidDeneb) Header() (interfaces.ExecutionData, error) {
 }
 
 // BlobKzgCommitments --
-func (b builderBidDeneb) BlobKzgCommitments() ([][]byte, error) {
-	return b.p.BlobKzgCommitments, nil
+func (b builderBidDeneb) BlobKzgCommitments() [][]byte {
+	return b.p.BlobKzgCommitments
 }
 
 type signedBuilderBidDeneb struct {
@@ -290,3 +291,95 @@ func (b signedBuilderBidDeneb) Version() int {
 func (b signedBuilderBidDeneb) IsNil() bool {
 	return b.p == nil
 }
+
+type builderBidElectra struct {
+	p *ethpb.BuilderBidElectra
+}
+
+// WrappedBuilderBidElectra is a constructor which wraps a protobuf bid into an interface.
+func WrappedBuilderBidElectra(p *ethpb.BuilderBidElectra) (Bid, error) {
+	w := builderBidElectra{p: p}
+	if w.IsNil() {
+		return nil, consensus_types.ErrNilObjectWrapped
+	}
+	return w, nil
+}
+
+// Version --
+func (b builderBidElectra) Version() int {
+	return version.Electra
+}
+
+// Value --
+func (b builderBidElectra) Value() primitives.Wei {
+	return primitives.LittleEndianBytesToWei(b.p.Value)
+}
+
+// Pubkey --
+func (b builderBidElectra) Pubkey() []byte {
+	return b.p.Pubkey
+}
+
+// IsNil --
+func (b builderBidElectra) IsNil() bool {
+	return b.p == nil
+}
+
+// HashTreeRoot --
+func (b builderBidElectra) HashTreeRoot() ([32]byte, error) {
+	return b.p.HashTreeRoot()
+}
+
+// HashTreeRootWith --
+func (b builderBidElectra) HashTreeRootWith(hh *ssz.Hasher) error {
+	return b.p.HashTreeRootWith(hh)
+}
+
+// Header --
+func (b builderBidElectra) Header() (interfaces.ExecutionData, error) {
+	// We have to convert big endian to little endian because the value is coming from the execution layer.
+	return blocks.WrappedExecutionPayloadHeaderDeneb(b.p.Header)
+}
+
+// ExecutionRequests --
+func (b builderBidElectra) ExecutionRequests() *v1.ExecutionRequests {
+	return b.p.ExecutionRequests // does not copy
+}
+
+// BlobKzgCommitments --
+func (b builderBidElectra) BlobKzgCommitments() [][]byte {
+	return b.p.BlobKzgCommitments
+}
+
+type signedBuilderBidElectra struct {
+	p *ethpb.SignedBuilderBidElectra
+}
+
+// WrappedSignedBuilderBidElectra is a constructor which wraps a protobuf signed bit into an interface.
+func WrappedSignedBuilderBidElectra(p *ethpb.SignedBuilderBidElectra) (SignedBid, error) {
+	w := signedBuilderBidElectra{p: p}
+	if w.IsNil() {
+		return nil, consensus_types.ErrNilObjectWrapped
+	}
+	return w, nil
+}
+
+// Message --
+func (b signedBuilderBidElectra) Message() (Bid, error) {
+	return WrappedBuilderBidElectra(b.p.Message)
+}
+
+// Signature --
+func (b signedBuilderBidElectra) Signature() []byte {
+	return b.p.Signature
+}
+
+// Version --
+func (b signedBuilderBidElectra) Version() int {
+	return version.Electra
+}
+
+// IsNil --
+func (b signedBuilderBidElectra) IsNil() bool {
+	return b.p == nil
+}

api/client/builder/client.go

@@ -12,18 +12,21 @@ import (
 	"strings"
 	"text/template"
 
+	"github.com/OffchainLabs/prysm/v6/api"
+	"github.com/OffchainLabs/prysm/v6/api/client"
+	"github.com/OffchainLabs/prysm/v6/api/server/structs"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	v1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/api"
-	"github.com/prysmaticlabs/prysm/v5/api/server/structs"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/monitoring/tracing"
-	v1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/runtime/version"
 	log "github.com/sirupsen/logrus"
-	"go.opencensus.io/trace"
+	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 )
 
 const (
@@ -33,9 +36,14 @@ const (
 	postRegisterValidatorPath  = "/eth/v1/builder/validators"
 )
 
-var errMalformedHostname = errors.New("hostname must include port, separated by one colon, like example.com:3500")
-var errMalformedRequest = errors.New("required request data are missing")
-var errNotBlinded = errors.New("submitted block is not blinded")
+var (
+	vrExample             = &ethpb.SignedValidatorRegistrationV1{}
+	vrSize                = vrExample.SizeSSZ()
+	errMalformedHostname  = errors.New("hostname must include port, separated by one colon, like example.com:3500")
+	errMalformedRequest   = errors.New("required request data are missing")
+	errNotBlinded         = errors.New("submitted block is not blinded")
+	errVersionUnsupported = errors.New("version is not supported")
+)
 
 // ClientOpt is a functional option for the Client type (http.Client wrapper)
 type ClientOpt func(*Client)
@@ -50,6 +58,12 @@ func WithObserver(m observer) ClientOpt {
 	}
 }
 
+func WithSSZ() ClientOpt {
+	return func(c *Client) {
+		c.sszEnabled = true
+	}
+}
+
 type requestLogger struct{}
 
 func (*requestLogger) observe(r *http.Request) (e error) {
@@ -58,7 +72,7 @@ func (*requestLogger) observe(r *http.Request) (e error) {
 		log.WithFields(log.Fields{
 			"bodyBase64": "(nil value)",
 			"url":        r.URL.String(),
-		}).Info("builder http request")
+		}).Info("Builder http request")
 		return nil
 	}
 	t := io.TeeReader(r.Body, b)
@@ -75,7 +89,7 @@ func (*requestLogger) observe(r *http.Request) (e error) {
 	log.WithFields(log.Fields{
 		"bodyBase64": string(body),
 		"url":        r.URL.String(),
-	}).Info("builder http request")
+	}).Info("Builder http request")
 
 	return nil
 }
@@ -87,15 +101,17 @@ type BuilderClient interface {
 	NodeURL() string
 	GetHeader(ctx context.Context, slot primitives.Slot, parentHash [32]byte, pubkey [48]byte) (SignedBid, error)
 	RegisterValidator(ctx context.Context, svr []*ethpb.SignedValidatorRegistrationV1) error
-	SubmitBlindedBlock(ctx context.Context, sb interfaces.ReadOnlySignedBeaconBlock) (interfaces.ExecutionData, *v1.BlobsBundle, error)
+	SubmitBlindedBlock(ctx context.Context, sb interfaces.ReadOnlySignedBeaconBlock) (interfaces.ExecutionData, v1.BlobsBundler, error)
+	SubmitBlindedBlockPostFulu(ctx context.Context, sb interfaces.ReadOnlySignedBeaconBlock) error
 	Status(ctx context.Context) error
 }
 
 // Client provides a collection of helper methods for calling Builder API endpoints.
 type Client struct {
-	hc      *http.Client
-	baseURL *url.URL
-	obvs    []observer
+	hc         *http.Client
+	baseURL    *url.URL
+	obvs       []observer
+	sszEnabled bool
 }
 
 // NewClient constructs a new client with the provided options (ex WithTimeout).
@@ -107,7 +123,7 @@ func NewClient(host string, opts ...ClientOpt) (*Client, error) {
 		return nil, err
 	}
 	c := &Client{
-		hc:      &http.Client{},
+		hc:      &http.Client{Transport: otelhttp.NewTransport(http.DefaultTransport)},
 		baseURL: u,
 	}
 	for _, o := range opts {
@@ -137,7 +153,8 @@ func (c *Client) NodeURL() string {
 type reqOption func(*http.Request)
 
 // do is a generic, opinionated request function to reduce boilerplate amongst the methods in this package api/client/builder.
-func (c *Client) do(ctx context.Context, method string, path string, body io.Reader, opts ...reqOption) (res []byte, err error) {
+// It validates that the HTTP response status matches the expectedStatus parameter.
+func (c *Client) do(ctx context.Context, method string, path string, body io.Reader, expectedStatus int, opts ...reqOption) (res []byte, header http.Header, err error) {
 	ctx, span := trace.StartSpan(ctx, "builder.client.do")
 	defer func() {
 		tracing.AnnotateError(span, err)
@@ -146,7 +163,7 @@ func (c *Client) do(ctx context.Context, method string, path string, body io.Rea
 
 	u := c.baseURL.ResolveReference(&url.URL{Path: path})
 
-	span.AddAttributes(trace.StringAttribute("url", u.String()),
+	span.SetAttributes(trace.StringAttribute("url", u.String()),
 		trace.StringAttribute("method", method))
 
 	req, err := http.NewRequestWithContext(ctx, method, u.String(), body)
@@ -172,15 +189,16 @@ func (c *Client) do(ctx context.Context, method string, path string, body io.Rea
 			log.WithError(closeErr).Error("Failed to close response body")
 		}
 	}()
-	if r.StatusCode != http.StatusOK {
-		err = non200Err(r)
+	if r.StatusCode != expectedStatus {
+		err = unexpectedStatusErr(r, expectedStatus)
 		return
 	}
-	res, err = io.ReadAll(r.Body)
+	res, err = io.ReadAll(io.LimitReader(r.Body, client.MaxBodySize))
 	if err != nil {
 		err = errors.Wrap(err, "error reading http response body from builder server")
 		return
 	}
+	header = r.Header
 	return
 }
 
@@ -210,48 +228,145 @@ func (c *Client) GetHeader(ctx context.Context, slot primitives.Slot, parentHash
 	if err != nil {
 		return nil, err
 	}
-	hb, err := c.do(ctx, http.MethodGet, path, nil)
+	var getOpts reqOption
+	if c.sszEnabled {
+		getOpts = func(r *http.Request) {
+			r.Header.Set("Accept", api.OctetStreamMediaType)
+		}
+	} else {
+		getOpts = func(r *http.Request) {
+			r.Header.Set("Accept", api.JsonMediaType)
+		}
+	}
+	data, header, err := c.do(ctx, http.MethodGet, path, nil, http.StatusOK, getOpts)
 	if err != nil {
-		return nil, err
+		return nil, errors.Wrap(err, "error getting header from builder server")
 	}
-	v := &VersionResponse{}
-	if err := json.Unmarshal(hb, v); err != nil {
-		return nil, errors.Wrapf(err, "error unmarshaling the builder GetHeader response, using slot=%d, parentHash=%#x, pubkey=%#x", slot, parentHash, pubkey)
+
+	bid, err := c.parseHeaderResponse(data, header, slot)
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"error rendering exec header template with slot=%d, parentHash=%#x, pubkey=%#x",
+			slot,
+			parentHash,
+			pubkey,
+		)
 	}
-	switch strings.ToLower(v.Version) {
-	case strings.ToLower(version.String(version.Deneb)):
-		hr := &ExecHeaderResponseDeneb{}
-		if err := json.Unmarshal(hb, hr); err != nil {
-			return nil, errors.Wrapf(err, "error unmarshaling the builder GetHeader response, using slot=%d, parentHash=%#x, pubkey=%#x", slot, parentHash, pubkey)
+	return bid, nil
+}
+
+func (c *Client) parseHeaderResponse(data []byte, header http.Header, slot primitives.Slot) (SignedBid, error) {
+	var versionHeader string
+	if c.sszEnabled || header.Get(api.VersionHeader) != "" {
+		versionHeader = header.Get(api.VersionHeader)
+	} else {
+		// If we don't have a version header, attempt to parse JSON for version
+		v := &VersionResponse{}
+		if err := json.Unmarshal(data, v); err != nil {
+			return nil, errors.Wrap(
+				err,
+				"error unmarshaling builder GetHeader response",
+			)
 		}
-		p, err := hr.ToProto()
-		if err != nil {
-			return nil, errors.Wrapf(err, "could not extract proto message from header")
-		}
-		return WrappedSignedBuilderBidDeneb(p)
-	case strings.ToLower(version.String(version.Capella)):
-		hr := &ExecHeaderResponseCapella{}
-		if err := json.Unmarshal(hb, hr); err != nil {
-			return nil, errors.Wrapf(err, "error unmarshaling the builder GetHeader response, using slot=%d, parentHash=%#x, pubkey=%#x", slot, parentHash, pubkey)
-		}
-		p, err := hr.ToProto()
-		if err != nil {
-			return nil, errors.Wrapf(err, "could not extract proto message from header")
-		}
-		return WrappedSignedBuilderBidCapella(p)
-	case strings.ToLower(version.String(version.Bellatrix)):
-		hr := &ExecHeaderResponse{}
-		if err := json.Unmarshal(hb, hr); err != nil {
-			return nil, errors.Wrapf(err, "error unmarshaling the builder GetHeader response, using slot=%d, parentHash=%#x, pubkey=%#x", slot, parentHash, pubkey)
-		}
-		p, err := hr.ToProto()
-		if err != nil {
-			return nil, errors.Wrap(err, "could not extract proto message from header")
-		}
-		return WrappedSignedBuilderBid(p)
-	default:
-		return nil, fmt.Errorf("unsupported header version %s", strings.ToLower(v.Version))
+		versionHeader = strings.ToLower(v.Version)
 	}
+
+	ver, err := version.FromString(versionHeader)
+	if err != nil {
+		return nil, errors.Wrap(err, fmt.Sprintf("unsupported header version %s", versionHeader))
+	}
+
+	if ver >= version.Electra {
+		return c.parseHeaderElectra(data, slot)
+	}
+	if ver >= version.Deneb {
+		return c.parseHeaderDeneb(data)
+	}
+	if ver >= version.Capella {
+		return c.parseHeaderCapella(data)
+	}
+	if ver >= version.Bellatrix {
+		return c.parseHeaderBellatrix(data)
+	}
+
+	return nil, fmt.Errorf("unsupported header version %s", versionHeader)
+}
+
+func (c *Client) parseHeaderElectra(data []byte, slot primitives.Slot) (SignedBid, error) {
+	if c.sszEnabled {
+		sb := &ethpb.SignedBuilderBidElectra{}
+		if err := sb.UnmarshalSSZ(data); err != nil {
+			return nil, errors.Wrap(err, "could not unmarshal SignedBuilderBidElectra SSZ")
+		}
+		return WrappedSignedBuilderBidElectra(sb)
+	}
+	hr := &ExecHeaderResponseElectra{}
+	if err := json.Unmarshal(data, hr); err != nil {
+		return nil, errors.Wrap(err, "could not unmarshal ExecHeaderResponseElectra JSON")
+	}
+	p, err := hr.ToProto(slot)
+	if err != nil {
+		return nil, errors.Wrap(err, "could not convert ExecHeaderResponseElectra to proto")
+	}
+	return WrappedSignedBuilderBidElectra(p)
+}
+
+func (c *Client) parseHeaderDeneb(data []byte) (SignedBid, error) {
+	if c.sszEnabled {
+		sb := &ethpb.SignedBuilderBidDeneb{}
+		if err := sb.UnmarshalSSZ(data); err != nil {
+			return nil, errors.Wrap(err, "could not unmarshal SignedBuilderBidDeneb SSZ")
+		}
+		return WrappedSignedBuilderBidDeneb(sb)
+	}
+	hr := &ExecHeaderResponseDeneb{}
+	if err := json.Unmarshal(data, hr); err != nil {
+		return nil, errors.Wrap(err, "could not unmarshal ExecHeaderResponseDeneb JSON")
+	}
+	p, err := hr.ToProto()
+	if err != nil {
+		return nil, errors.Wrap(err, "could not convert ExecHeaderResponseDeneb to proto")
+	}
+	return WrappedSignedBuilderBidDeneb(p)
+}
+
+func (c *Client) parseHeaderCapella(data []byte) (SignedBid, error) {
+	if c.sszEnabled {
+		sb := &ethpb.SignedBuilderBidCapella{}
+		if err := sb.UnmarshalSSZ(data); err != nil {
+			return nil, errors.Wrap(err, "could not unmarshal SignedBuilderBidCapella SSZ")
+		}
+		return WrappedSignedBuilderBidCapella(sb)
+	}
+	hr := &ExecHeaderResponseCapella{}
+	if err := json.Unmarshal(data, hr); err != nil {
+		return nil, errors.Wrap(err, "could not unmarshal ExecHeaderResponseCapella JSON")
+	}
+	p, err := hr.ToProto()
+	if err != nil {
+		return nil, errors.Wrap(err, "could not convert ExecHeaderResponseCapella to proto")
+	}
+	return WrappedSignedBuilderBidCapella(p)
+}
+
+func (c *Client) parseHeaderBellatrix(data []byte) (SignedBid, error) {
+	if c.sszEnabled {
+		sb := &ethpb.SignedBuilderBid{}
+		if err := sb.UnmarshalSSZ(data); err != nil {
+			return nil, errors.Wrap(err, "could not unmarshal SignedBuilderBid SSZ")
+		}
+		return WrappedSignedBuilderBid(sb)
+	}
+	hr := &ExecHeaderResponse{}
+	if err := json.Unmarshal(data, hr); err != nil {
+		return nil, errors.Wrap(err, "could not unmarshal ExecHeaderResponse JSON")
+	}
+	p, err := hr.ToProto()
+	if err != nil {
+		return nil, errors.Wrap(err, "could not convert ExecHeaderResponse to proto")
+	}
+	return WrappedSignedBuilderBid(p)
 }
 
 // RegisterValidator encodes the SignedValidatorRegistrationV1 message to json (including hex-encoding the byte
@@ -259,73 +374,281 @@ func (c *Client) GetHeader(ctx context.Context, slot primitives.Slot, parentHash
 func (c *Client) RegisterValidator(ctx context.Context, svr []*ethpb.SignedValidatorRegistrationV1) error {
 	ctx, span := trace.StartSpan(ctx, "builder.client.RegisterValidator")
 	defer span.End()
-	span.AddAttributes(trace.Int64Attribute("num_reqs", int64(len(svr))))
+	span.SetAttributes(trace.Int64Attribute("num_reqs", int64(len(svr))))
 
 	if len(svr) == 0 {
 		err := errors.Wrap(errMalformedRequest, "empty validator registration list")
 		tracing.AnnotateError(span, err)
 		return err
 	}
+
+	var (
+		body     []byte
+		err      error
+		postOpts reqOption
+	)
+	if c.sszEnabled {
+		postOpts = func(r *http.Request) {
+			r.Header.Set("Content-Type", api.OctetStreamMediaType)
+			r.Header.Set("Accept", api.OctetStreamMediaType)
+		}
+		body, err = sszValidatorRegisterRequest(svr)
+		if err != nil {
+			err := errors.Wrap(err, "error ssz encoding the SignedValidatorRegistration value body in RegisterValidator")
+			tracing.AnnotateError(span, err)
+			return err
+		}
+	} else {
+		postOpts = func(r *http.Request) {
+			r.Header.Set("Content-Type", api.JsonMediaType)
+			r.Header.Set("Accept", api.JsonMediaType)
+		}
+		body, err = jsonValidatorRegisterRequest(svr)
+		if err != nil {
+			err := errors.Wrap(err, "error json encoding the SignedValidatorRegistration value body in RegisterValidator")
+			tracing.AnnotateError(span, err)
+			return err
+		}
+	}
+
+	if _, _, err = c.do(ctx, http.MethodPost, postRegisterValidatorPath, bytes.NewBuffer(body), http.StatusOK, postOpts); err != nil {
+		return errors.Wrap(err, "do")
+	}
+	log.WithField("registrationCount", len(svr)).Debug("Successfully registered validator(s) on builder")
+	return nil
+}
+
+func jsonValidatorRegisterRequest(svr []*ethpb.SignedValidatorRegistrationV1) ([]byte, error) {
 	vs := make([]*structs.SignedValidatorRegistration, len(svr))
 	for i := 0; i < len(svr); i++ {
 		vs[i] = structs.SignedValidatorRegistrationFromConsensus(svr[i])
 	}
 	body, err := json.Marshal(vs)
 	if err != nil {
-		err := errors.Wrap(err, "error encoding the SignedValidatorRegistration value body in RegisterValidator")
-		tracing.AnnotateError(span, err)
-		return err
+		return nil, err
 	}
+	return body, nil
+}
 
-	_, err = c.do(ctx, http.MethodPost, postRegisterValidatorPath, bytes.NewBuffer(body))
-	return err
+func sszValidatorRegisterRequest(svr []*ethpb.SignedValidatorRegistrationV1) ([]byte, error) {
+	if uint64(len(svr)) > params.BeaconConfig().ValidatorRegistryLimit {
+		return nil, errors.Wrap(errMalformedRequest, "validator registry limit exceeded")
+	}
+	ssz := make([]byte, vrSize*len(svr))
+	for i, vr := range svr {
+		sszrep, err := vr.MarshalSSZ()
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to marshal validator registry ssz")
+		}
+		copy(ssz[i*vrSize:(i+1)*vrSize], sszrep)
+	}
+	return ssz, nil
 }
 
 var errResponseVersionMismatch = errors.New("builder API response uses a different version than requested in " + api.VersionHeader + " header")
 
+func getVersionsBlockToPayload(blockVersion int) (int, error) {
+	if blockVersion >= version.Fulu {
+		return version.Fulu, nil
+	}
+	if blockVersion >= version.Deneb {
+		return version.Deneb, nil
+	}
+	if blockVersion == version.Capella {
+		return version.Capella, nil
+	}
+	if blockVersion == version.Bellatrix {
+		return version.Bellatrix, nil
+	}
+	return 0, errors.Wrapf(errVersionUnsupported, "block version %d", blockVersion)
+}
+
 // SubmitBlindedBlock calls the builder API endpoint that binds the validator to the builder and submits the block.
 // The response is the full execution payload used to create the blinded block.
-func (c *Client) SubmitBlindedBlock(ctx context.Context, sb interfaces.ReadOnlySignedBeaconBlock) (interfaces.ExecutionData, *v1.BlobsBundle, error) {
+func (c *Client) SubmitBlindedBlock(ctx context.Context, sb interfaces.ReadOnlySignedBeaconBlock) (interfaces.ExecutionData, v1.BlobsBundler, error) {
+	body, postOpts, err := c.buildBlindedBlockRequest(sb)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// post the blinded block - the execution payload response should contain the unblinded payload, along with the
+	// blobs bundle if it is post deneb.
+	data, header, err := c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body), http.StatusOK, postOpts)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "error posting the blinded block to the builder api")
+	}
+
+	ver, err := c.checkBlockVersion(data, header)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	expectedPayloadVer, err := getVersionsBlockToPayload(sb.Version())
+	if err != nil {
+		return nil, nil, err
+	}
+	gotPayloadVer, err := getVersionsBlockToPayload(ver)
+	if err != nil {
+		return nil, nil, err
+	}
+	if expectedPayloadVer != gotPayloadVer {
+		return nil, nil, errors.Wrapf(errResponseVersionMismatch, "expected payload version %d, got %d", expectedPayloadVer, gotPayloadVer)
+	}
+
+	ed, blobs, err := c.parseBlindedBlockResponse(data, ver)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return ed, blobs, nil
+}
+
+// SubmitBlindedBlockPostFulu calls the builder API endpoint post-Fulu where relays only return status codes.
+// This method is used after the Fulu fork when MEV-boost relays no longer return execution payloads.
+func (c *Client) SubmitBlindedBlockPostFulu(ctx context.Context, sb interfaces.ReadOnlySignedBeaconBlock) error {
+	body, postOpts, err := c.buildBlindedBlockRequest(sb)
+	if err != nil {
+		return err
+	}
+
+	// Post the blinded block - the response should only contain a status code (no payload)
+	_, _, err = c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body), http.StatusAccepted, postOpts)
+	if err != nil {
+		return errors.Wrap(err, "error posting the blinded block to the builder api post-Fulu")
+	}
+
+	// Success is indicated by no error (status 202)
+	return nil
+}
+
+func (c *Client) checkBlockVersion(respBytes []byte, header http.Header) (int, error) {
+	var versionHeader string
+	if c.sszEnabled {
+		versionHeader = strings.ToLower(header.Get(api.VersionHeader))
+	} else {
+		// fallback to JSON-based version extraction
+		v := &VersionResponse{}
+		if err := json.Unmarshal(respBytes, v); err != nil {
+			return 0, errors.Wrapf(err, "error unmarshaling JSON version fallback")
+		}
+		versionHeader = strings.ToLower(v.Version)
+	}
+
+	ver, err := version.FromString(versionHeader)
+	if err != nil {
+		return 0, errors.Wrapf(err, "unsupported header version %s", versionHeader)
+	}
+
+	return ver, nil
+}
+
+// Helper: build request body for SubmitBlindedBlock
+func (c *Client) buildBlindedBlockRequest(sb interfaces.ReadOnlySignedBeaconBlock) ([]byte, reqOption, error) {
 	if !sb.IsBlinded() {
 		return nil, nil, errNotBlinded
 	}
 
-	// massage the proto struct type data into the api response type.
+	if c.sszEnabled {
+		body, err := sb.MarshalSSZ()
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "could not marshal SSZ for blinded block")
+		}
+		opt := func(r *http.Request) {
+			r.Header.Set(api.VersionHeader, version.String(sb.Version()))
+			r.Header.Set("Content-Type", api.OctetStreamMediaType)
+			r.Header.Set("Accept", api.OctetStreamMediaType)
+		}
+		return body, opt, nil
+	}
+
 	mj, err := structs.SignedBeaconBlockMessageJsoner(sb)
 	if err != nil {
 		return nil, nil, errors.Wrap(err, "error generating blinded beacon block post request")
 	}
-
 	body, err := json.Marshal(mj)
 	if err != nil {
-		return nil, nil, errors.Wrap(err, "error marshaling blinded block post request to json")
+		return nil, nil, errors.Wrap(err, "error marshaling blinded block to JSON")
 	}
-	postOpts := func(r *http.Request) {
-		r.Header.Add("Eth-Consensus-Version", version.String(sb.Version()))
+	opt := func(r *http.Request) {
+		r.Header.Set(api.VersionHeader, version.String(sb.Version()))
 		r.Header.Set("Content-Type", api.JsonMediaType)
 		r.Header.Set("Accept", api.JsonMediaType)
 	}
-	// post the blinded block - the execution payload response should contain the unblinded payload, along with the
-	// blobs bundle if it is post deneb.
-	rb, err := c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body), postOpts)
-	if err != nil {
-		return nil, nil, errors.Wrap(err, "error posting the blinded block to the builder api")
+	return body, opt, nil
+}
+
+// Helper: parse the response returned by SubmitBlindedBlock
+func (c *Client) parseBlindedBlockResponse(
+	respBytes []byte,
+	forkVersion int,
+) (interfaces.ExecutionData, v1.BlobsBundler, error) {
+	if c.sszEnabled {
+		return c.parseBlindedBlockResponseSSZ(respBytes, forkVersion)
 	}
-	// ExecutionPayloadResponse parses just the outer container and the Value key, enabling it to use the .Value
-	// key to determine which underlying data type to use to finish the unmarshaling.
+	return c.parseBlindedBlockResponseJSON(respBytes, forkVersion)
+}
+
+func (c *Client) parseBlindedBlockResponseSSZ(
+	respBytes []byte,
+	forkVersion int,
+) (interfaces.ExecutionData, v1.BlobsBundler, error) {
+	if forkVersion >= version.Fulu {
+		payloadAndBlobs := &v1.ExecutionPayloadDenebAndBlobsBundleV2{}
+		if err := payloadAndBlobs.UnmarshalSSZ(respBytes); err != nil {
+			return nil, nil, errors.Wrap(err, "unable to unmarshal ExecutionPayloadDenebAndBlobsBundleV2 SSZ")
+		}
+		ed, err := blocks.NewWrappedExecutionData(payloadAndBlobs.Payload)
+		if err != nil {
+			return nil, nil, errors.Wrapf(err, "unable to wrap execution data for %s", version.String(forkVersion))
+		}
+		return ed, payloadAndBlobs.BlobsBundle, nil
+	} else if forkVersion >= version.Deneb {
+		payloadAndBlobs := &v1.ExecutionPayloadDenebAndBlobsBundle{}
+		if err := payloadAndBlobs.UnmarshalSSZ(respBytes); err != nil {
+			return nil, nil, errors.Wrap(err, "unable to unmarshal ExecutionPayloadDenebAndBlobsBundle SSZ")
+		}
+		ed, err := blocks.NewWrappedExecutionData(payloadAndBlobs.Payload)
+		if err != nil {
+			return nil, nil, errors.Wrapf(err, "unable to wrap execution data for %s", version.String(forkVersion))
+		}
+		return ed, payloadAndBlobs.BlobsBundle, nil
+	} else if forkVersion >= version.Capella {
+		payload := &v1.ExecutionPayloadCapella{}
+		if err := payload.UnmarshalSSZ(respBytes); err != nil {
+			return nil, nil, errors.Wrap(err, "unable to unmarshal ExecutionPayloadCapella SSZ")
+		}
+		ed, err := blocks.NewWrappedExecutionData(payload)
+		if err != nil {
+			return nil, nil, errors.Wrapf(err, "unable to wrap execution data for %s", version.String(forkVersion))
+		}
+		return ed, nil, nil
+	} else if forkVersion >= version.Bellatrix {
+		payload := &v1.ExecutionPayload{}
+		if err := payload.UnmarshalSSZ(respBytes); err != nil {
+			return nil, nil, errors.Wrap(err, "unable to unmarshal ExecutionPayload SSZ")
+		}
+		ed, err := blocks.NewWrappedExecutionData(payload)
+		if err != nil {
+			return nil, nil, errors.Wrapf(err, "unable to wrap execution data for %s", version.String(forkVersion))
+		}
+		return ed, nil, nil
+	} else {
+		return nil, nil, fmt.Errorf("unsupported header version %s", version.String(forkVersion))
+	}
+}
+
+func (c *Client) parseBlindedBlockResponseJSON(
+	respBytes []byte,
+	forkVersion int,
+) (interfaces.ExecutionData, *v1.BlobsBundle, error) {
 	ep := &ExecutionPayloadResponse{}
-	if err := json.Unmarshal(rb, ep); err != nil {
-		return nil, nil, errors.Wrap(err, "error unmarshaling the builder ExecutionPayloadResponse")
+	if err := json.Unmarshal(respBytes, ep); err != nil {
+		return nil, nil, errors.Wrap(err, "error unmarshaling ExecutionPayloadResponse")
 	}
-	if strings.ToLower(ep.Version) != version.String(sb.Version()) {
-		return nil, nil, errors.Wrapf(errResponseVersionMismatch, "req=%s, recv=%s", strings.ToLower(ep.Version), version.String(sb.Version()))
-	}
-	// This parses the rest of the response and returns the inner data field.
 	pp, err := ep.ParsePayload()
 	if err != nil {
-		return nil, nil, errors.Wrapf(err, "failed to parse execution payload from builder with version=%s", ep.Version)
+		return nil, nil, errors.Wrapf(err, "failed to parse payload with version=%s", ep.Version)
 	}
-	// Get the payload as a proto.Message so it can be wrapped as an execution payload interface.
 	pb, err := pp.PayloadProto()
 	if err != nil {
 		return nil, nil, err
@@ -334,11 +657,13 @@ func (c *Client) SubmitBlindedBlock(ctx context.Context, sb interfaces.ReadOnlyS
 	if err != nil {
 		return nil, nil, err
 	}
+
+	// Check if it contains blobs
 	bb, ok := pp.(BlobBundler)
 	if ok {
 		bbpb, err := bb.BundleProto()
 		if err != nil {
-			return nil, nil, errors.Wrapf(err, "failed to extract blobs bundle from builder response with version=%s", ep.Version)
+			return nil, nil, errors.Wrapf(err, "failed to extract blobs bundle from version=%s", ep.Version)
 		}
 		return ed, bbpb, nil
 	}
@@ -349,12 +674,15 @@ func (c *Client) SubmitBlindedBlock(ctx context.Context, sb interfaces.ReadOnlyS
 // response, and an error response may have an error message. This method will return a nil value for error in the
 // happy path, and an error with information about the server response body for a non-200 response.
 func (c *Client) Status(ctx context.Context) error {
-	_, err := c.do(ctx, http.MethodGet, getStatus, nil)
+	getOpts := func(r *http.Request) {
+		r.Header.Set("Accept", api.JsonMediaType)
+	}
+	_, _, err := c.do(ctx, http.MethodGet, getStatus, nil, http.StatusOK, getOpts)
 	return err
 }
 
-func non200Err(response *http.Response) error {
-	bodyBytes, err := io.ReadAll(response.Body)
+func unexpectedStatusErr(response *http.Response, expected int) error {
+	bodyBytes, err := io.ReadAll(io.LimitReader(response.Body, client.MaxErrBodySize))
 	var errMessage ErrorMessage
 	var body string
 	if err != nil {
@@ -362,8 +690,20 @@ func non200Err(response *http.Response) error {
 	} else {
 		body = "response body:\n" + string(bodyBytes)
 	}
-	msg := fmt.Sprintf("code=%d, url=%s, body=%s", response.StatusCode, response.Request.URL, body)
+	msg := fmt.Sprintf("expected=%d, got=%d, url=%s, body=%s", expected, response.StatusCode, response.Request.URL, body)
 	switch response.StatusCode {
+	case http.StatusUnsupportedMediaType:
+		log.WithError(ErrUnsupportedMediaType).Debug(msg)
+		if jsonErr := json.Unmarshal(bodyBytes, &errMessage); jsonErr != nil {
+			return errors.Wrap(jsonErr, "unable to read response body")
+		}
+		return errors.Wrap(ErrUnsupportedMediaType, errMessage.Message)
+	case http.StatusNotAcceptable:
+		log.WithError(ErrNotAcceptable).Debug(msg)
+		if jsonErr := json.Unmarshal(bodyBytes, &errMessage); jsonErr != nil {
+			return errors.Wrap(jsonErr, "unable to read response body")
+		}
+		return errors.Wrap(ErrNotAcceptable, errMessage.Message)
 	case http.StatusNoContent:
 		log.WithError(ErrNoContent).Debug(msg)
 		return ErrNoContent

api/client/builder/errors.go

@@ -15,3 +15,9 @@ var ErrBadRequest = errors.Wrap(ErrNotOK, "recv 400 BadRequest response from API
 // ErrNoContent specifically means that a '204 - No Content' response was received from the API.
 // Typically, a 204 is a success but in this case for the Header API means No header is available
 var ErrNoContent = errors.New("recv 204 no content response from API, No header is available")
+
+// ErrUnsupportedMediaType specifically means that a '415 - Unsupported Media Type' was received from the API.
+var ErrUnsupportedMediaType = errors.Wrap(ErrNotOK, "The media type in \"Content-Type\" header is unsupported, and the request has been rejected. This occurs when a HTTP request supplies a payload in a content-type that the server is not able to handle.")
+
+// ErrNotAcceptable specifically means that a '406 - Not Acceptable' was received from the API.
+var ErrNotAcceptable = errors.Wrap(ErrNotOK, "The accept header value is not acceptable")

api/client/builder/testing/BUILD.bazel

@@ -3,7 +3,7 @@ load("@prysm//tools/go:def.bzl", "go_library")
 go_library(
     name = "go_default_library",
     srcs = ["mock.go"],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/builder/testing",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/client/builder/testing",
     visibility = ["//visibility:public"],
     deps = [
         "//api/client/builder:go_default_library",

api/client/builder/testing/mock.go

@@ -3,12 +3,12 @@ package testing
 import (
 	"context"
 
-	"github.com/prysmaticlabs/prysm/v5/api/client/builder"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	v1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/api/client/builder"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	v1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 )
 
 // MockClient is a mock implementation of BuilderClient.
@@ -41,10 +41,15 @@ func (m MockClient) RegisterValidator(_ context.Context, svr []*ethpb.SignedVali
 }
 
 // SubmitBlindedBlock --
-func (MockClient) SubmitBlindedBlock(_ context.Context, _ interfaces.ReadOnlySignedBeaconBlock) (interfaces.ExecutionData, *v1.BlobsBundle, error) {
+func (MockClient) SubmitBlindedBlock(_ context.Context, _ interfaces.ReadOnlySignedBeaconBlock) (interfaces.ExecutionData, v1.BlobsBundler, error) {
 	return nil, nil, nil
 }
 
+// SubmitBlindedBlockPostFulu --
+func (MockClient) SubmitBlindedBlockPostFulu(_ context.Context, _ interfaces.ReadOnlySignedBeaconBlock) error {
+	return nil
+}
+
 // Status --
 func (MockClient) Status(_ context.Context) error {
 	return nil

api/client/builder/types_test.go

@@ -11,18 +11,18 @@ import (
 	"os"
 	"testing"
 
+	"github.com/OffchainLabs/prysm/v6/api/server/structs"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	consensusblocks "github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/math"
+	v1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	eth "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/go-bitfield"
-	"github.com/prysmaticlabs/prysm/v5/api/server/structs"
-	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
-	consensusblocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/math"
-	v1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/runtime/version"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
 )
 
 func ezDecode(t *testing.T, s string) []byte {
@@ -154,6 +154,64 @@ var testExampleHeaderResponseDeneb = `{
   }
 }`
 
+var testExampleHeaderResponseElectra = `{
+  "version": "electra",
+  "data": {
+    "message": {
+      "header": {
+        "parent_hash": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
+        "fee_recipient": "0xabcf8e0d4e9587369b2301d0790347320302cc09",
+        "state_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
+        "receipts_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
+        "logs_bloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
+        "prev_randao": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
+        "block_number": "1",
+        "gas_limit": "1",
+        "gas_used": "1",
+        "timestamp": "1",
+        "extra_data": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
+        "base_fee_per_gas": "1",
+        "blob_gas_used": "1",
+        "excess_blob_gas": "1",
+        "block_hash": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
+        "transactions_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
+        "withdrawals_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"
+      },
+      "blob_kzg_commitments": [
+        "0xa94170080872584e54a1cf092d845703b13907f2e6b3b1c0ad573b910530499e3bcd48c6378846b80d2bfa58c81cf3d5"
+      ],
+      "execution_requests": {
+        "deposits": [
+          {
+            "pubkey": "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a",
+            "withdrawal_credentials": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
+            "amount": "1",
+            "signature": "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505",
+            "index": "1"
+          }
+        ],
+        "withdrawals": [
+          {
+            "source_address": "0xabcf8e0d4e9587369b2301d0790347320302cc09",
+            "validator_pubkey": "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a",
+            "amount": "1"
+          }
+        ],
+        "consolidations": [
+          {
+            "source_address": "0xabcf8e0d4e9587369b2301d0790347320302cc09",
+            "source_pubkey": "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a",
+            "target_pubkey": "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"
+          }
+        ]
+      },
+      "value": "652312848583266388373324160190187140051835877600158453279131187530910662656",
+      "pubkey": "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"
+    },
+    "signature": "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"
+  }
+}`
+
 var testExampleHeaderResponseDenebNoBundle = `{
   "version": "deneb",
   "data": {
@@ -270,72 +328,72 @@ func TestExecutionHeaderResponseUnmarshal(t *testing.T) {
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.ParentHash),
+			actual:   hr.Data.Message.Header.ParentHash,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.ParentHash",
 		},
 		{
 			expected: "0xabcf8e0d4e9587369b2301d0790347320302cc09",
-			actual:   hexutil.Encode(hr.Data.Message.Header.FeeRecipient),
+			actual:   hr.Data.Message.Header.FeeRecipient,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.FeeRecipient",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.StateRoot),
+			actual:   hr.Data.Message.Header.StateRoot,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.StateRoot",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.ReceiptsRoot),
+			actual:   hr.Data.Message.Header.ReceiptsRoot,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.ReceiptsRoot",
 		},
 		{
 			expected: "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
-			actual:   hexutil.Encode(hr.Data.Message.Header.LogsBloom),
+			actual:   hr.Data.Message.Header.LogsBloom,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.LogsBloom",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.PrevRandao),
+			actual:   hr.Data.Message.Header.PrevRandao,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.PrevRandao",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.BlockNumber),
+			actual:   hr.Data.Message.Header.BlockNumber,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.BlockNumber",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.GasLimit),
+			actual:   hr.Data.Message.Header.GasLimit,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.GasLimit",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.GasUsed),
+			actual:   hr.Data.Message.Header.GasUsed,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.GasUsed",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.Timestamp),
+			actual:   hr.Data.Message.Header.Timestamp,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.Timestamp",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.ExtraData),
+			actual:   hr.Data.Message.Header.ExtraData,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.ExtraData",
 		},
 		{
 			expected: "452312848583266388373324160190187140051835877600158453279131187530910662656",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.BaseFeePerGas),
+			actual:   hr.Data.Message.Header.BaseFeePerGas,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.BaseFeePerGas",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.BlockHash),
+			actual:   hr.Data.Message.Header.BlockHash,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.BlockHash",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.TransactionsRoot),
+			actual:   hr.Data.Message.Header.TransactionsRoot,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.TransactionsRoot",
 		},
 	}
@@ -369,77 +427,77 @@ func TestExecutionHeaderResponseCapellaUnmarshal(t *testing.T) {
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.ParentHash),
+			actual:   hr.Data.Message.Header.ParentHash,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.ParentHash",
 		},
 		{
 			expected: "0xabcf8e0d4e9587369b2301d0790347320302cc09",
-			actual:   hexutil.Encode(hr.Data.Message.Header.FeeRecipient),
+			actual:   hr.Data.Message.Header.FeeRecipient,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.FeeRecipient",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.StateRoot),
+			actual:   hr.Data.Message.Header.StateRoot,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.StateRoot",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.ReceiptsRoot),
+			actual:   hr.Data.Message.Header.ReceiptsRoot,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.ReceiptsRoot",
 		},
 		{
 			expected: "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
-			actual:   hexutil.Encode(hr.Data.Message.Header.LogsBloom),
+			actual:   hr.Data.Message.Header.LogsBloom,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.LogsBloom",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.PrevRandao),
+			actual:   hr.Data.Message.Header.PrevRandao,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.PrevRandao",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.BlockNumber),
+			actual:   hr.Data.Message.Header.BlockNumber,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.BlockNumber",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.GasLimit),
+			actual:   hr.Data.Message.Header.GasLimit,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.GasLimit",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.GasUsed),
+			actual:   hr.Data.Message.Header.GasUsed,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.GasUsed",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.Timestamp),
+			actual:   hr.Data.Message.Header.Timestamp,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.Timestamp",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.ExtraData),
+			actual:   hr.Data.Message.Header.ExtraData,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.ExtraData",
 		},
 		{
 			expected: "452312848583266388373324160190187140051835877600158453279131187530910662656",
-			actual:   fmt.Sprintf("%d", hr.Data.Message.Header.BaseFeePerGas),
+			actual:   hr.Data.Message.Header.BaseFeePerGas,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.BaseFeePerGas",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.BlockHash),
+			actual:   hr.Data.Message.Header.BlockHash,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.BlockHash",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.TransactionsRoot),
+			actual:   hr.Data.Message.Header.TransactionsRoot,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.TransactionsRoot",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(hr.Data.Message.Header.WithdrawalsRoot),
+			actual:   hr.Data.Message.Header.WithdrawalsRoot,
 			name:     "ExecHeaderResponse.ExecutionPayloadHeader.WithdrawalsRoot",
 		},
 	}
@@ -809,88 +867,6 @@ var testExampleExecutionPayloadDenebDifferentProofCount = fmt.Sprintf(`{
   }
 }`, hexutil.Encode(make([]byte, fieldparams.BlobLength)))
 
-func TestExecutionPayloadResponseUnmarshal(t *testing.T) {
-	epr := &ExecPayloadResponse{}
-	require.NoError(t, json.Unmarshal([]byte(testExampleExecutionPayload), epr))
-	cases := []struct {
-		expected string
-		actual   string
-		name     string
-	}{
-		{
-			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ParentHash),
-			name:     "ExecPayloadResponse.ExecutionPayload.ParentHash",
-		},
-		{
-			expected: "0xabcf8e0d4e9587369b2301d0790347320302cc09",
-			actual:   hexutil.Encode(epr.Data.FeeRecipient),
-			name:     "ExecPayloadResponse.ExecutionPayload.FeeRecipient",
-		},
-		{
-			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.StateRoot),
-			name:     "ExecPayloadResponse.ExecutionPayload.StateRoot",
-		},
-		{
-			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ReceiptsRoot),
-			name:     "ExecPayloadResponse.ExecutionPayload.ReceiptsRoot",
-		},
-		{
-			expected: "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
-			actual:   hexutil.Encode(epr.Data.LogsBloom),
-			name:     "ExecPayloadResponse.ExecutionPayload.LogsBloom",
-		},
-		{
-			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.PrevRandao),
-			name:     "ExecPayloadResponse.ExecutionPayload.PrevRandao",
-		},
-		{
-			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.BlockNumber),
-			name:     "ExecPayloadResponse.ExecutionPayload.BlockNumber",
-		},
-		{
-			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.GasLimit),
-			name:     "ExecPayloadResponse.ExecutionPayload.GasLimit",
-		},
-		{
-			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.GasUsed),
-			name:     "ExecPayloadResponse.ExecutionPayload.GasUsed",
-		},
-		{
-			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.Timestamp),
-			name:     "ExecPayloadResponse.ExecutionPayload.Timestamp",
-		},
-		{
-			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ExtraData),
-			name:     "ExecPayloadResponse.ExecutionPayload.ExtraData",
-		},
-		{
-			expected: "452312848583266388373324160190187140051835877600158453279131187530910662656",
-			actual:   fmt.Sprintf("%d", epr.Data.BaseFeePerGas),
-			name:     "ExecPayloadResponse.ExecutionPayload.BaseFeePerGas",
-		},
-		{
-			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.BlockHash),
-			name:     "ExecPayloadResponse.ExecutionPayload.BlockHash",
-		},
-	}
-	for _, c := range cases {
-		require.Equal(t, c.expected, c.actual, fmt.Sprintf("unexpected value for field %s", c.name))
-	}
-	require.Equal(t, 1, len(epr.Data.Transactions))
-	txHash := "0x02f878831469668303f51d843b9ac9f9843b9aca0082520894c93269b73096998db66be0441e836d873535cb9c8894a19041886f000080c001a031cc29234036afbf9a1fb9476b463367cb1f957ac0b919b69bbc798436e604aaa018c4e9c3914eb27aadd0b91e10b18655739fcf8c1fc398763a9f1beecb8ddc86"
-	require.Equal(t, txHash, hexutil.Encode(epr.Data.Transactions[0]))
-}
-
 func TestExecutionPayloadResponseCapellaUnmarshal(t *testing.T) {
 	epr := &ExecPayloadResponseCapella{}
 	require.NoError(t, json.Unmarshal([]byte(testExampleExecutionPayloadCapella), epr))
@@ -901,67 +877,67 @@ func TestExecutionPayloadResponseCapellaUnmarshal(t *testing.T) {
 	}{
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ParentHash),
+			actual:   epr.Data.ParentHash,
 			name:     "ExecPayloadResponse.ExecutionPayload.ParentHash",
 		},
 		{
 			expected: "0xabcf8e0d4e9587369b2301d0790347320302cc09",
-			actual:   hexutil.Encode(epr.Data.FeeRecipient),
+			actual:   epr.Data.FeeRecipient,
 			name:     "ExecPayloadResponse.ExecutionPayload.FeeRecipient",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.StateRoot),
+			actual:   epr.Data.StateRoot,
 			name:     "ExecPayloadResponse.ExecutionPayload.StateRoot",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ReceiptsRoot),
+			actual:   epr.Data.ReceiptsRoot,
 			name:     "ExecPayloadResponse.ExecutionPayload.ReceiptsRoot",
 		},
 		{
 			expected: "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
-			actual:   hexutil.Encode(epr.Data.LogsBloom),
+			actual:   epr.Data.LogsBloom,
 			name:     "ExecPayloadResponse.ExecutionPayload.LogsBloom",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.PrevRandao),
+			actual:   epr.Data.PrevRandao,
 			name:     "ExecPayloadResponse.ExecutionPayload.PrevRandao",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.BlockNumber),
+			actual:   epr.Data.BlockNumber,
 			name:     "ExecPayloadResponse.ExecutionPayload.BlockNumber",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.GasLimit),
+			actual:   epr.Data.GasLimit,
 			name:     "ExecPayloadResponse.ExecutionPayload.GasLimit",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.GasUsed),
+			actual:   epr.Data.GasUsed,
 			name:     "ExecPayloadResponse.ExecutionPayload.GasUsed",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.Timestamp),
+			actual:   epr.Data.Timestamp,
 			name:     "ExecPayloadResponse.ExecutionPayload.Timestamp",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ExtraData),
+			actual:   epr.Data.ExtraData,
 			name:     "ExecPayloadResponse.ExecutionPayload.ExtraData",
 		},
 		{
 			expected: "452312848583266388373324160190187140051835877600158453279131187530910662656",
-			actual:   fmt.Sprintf("%d", epr.Data.BaseFeePerGas),
+			actual:   epr.Data.BaseFeePerGas,
 			name:     "ExecPayloadResponse.ExecutionPayload.BaseFeePerGas",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.BlockHash),
+			actual:   epr.Data.BlockHash,
 			name:     "ExecPayloadResponse.ExecutionPayload.BlockHash",
 		},
 	}
@@ -970,14 +946,14 @@ func TestExecutionPayloadResponseCapellaUnmarshal(t *testing.T) {
 	}
 	require.Equal(t, 1, len(epr.Data.Transactions))
 	txHash := "0x02f878831469668303f51d843b9ac9f9843b9aca0082520894c93269b73096998db66be0441e836d873535cb9c8894a19041886f000080c001a031cc29234036afbf9a1fb9476b463367cb1f957ac0b919b69bbc798436e604aaa018c4e9c3914eb27aadd0b91e10b18655739fcf8c1fc398763a9f1beecb8ddc86"
-	require.Equal(t, txHash, hexutil.Encode(epr.Data.Transactions[0]))
+	require.Equal(t, txHash, epr.Data.Transactions[0])
 
 	require.Equal(t, 1, len(epr.Data.Withdrawals))
 	w := epr.Data.Withdrawals[0]
-	assert.Equal(t, uint64(1), w.Index.Uint64())
-	assert.Equal(t, uint64(1), w.ValidatorIndex.Uint64())
-	assert.DeepEqual(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943", w.Address.String())
-	assert.Equal(t, uint64(1), w.Amount.Uint64())
+	assert.Equal(t, "1", w.WithdrawalIndex)
+	assert.Equal(t, "1", w.ValidatorIndex)
+	assert.DeepEqual(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943", w.ExecutionAddress)
+	assert.Equal(t, "1", w.Amount)
 }
 
 func TestExecutionPayloadResponseDenebUnmarshal(t *testing.T) {
@@ -990,77 +966,77 @@ func TestExecutionPayloadResponseDenebUnmarshal(t *testing.T) {
 	}{
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ExecutionPayload.ParentHash),
+			actual:   epr.Data.ExecutionPayload.ParentHash,
 			name:     "ExecPayloadResponse.ExecutionPayload.ParentHash",
 		},
 		{
 			expected: "0xabcf8e0d4e9587369b2301d0790347320302cc09",
-			actual:   hexutil.Encode(epr.Data.ExecutionPayload.FeeRecipient),
+			actual:   epr.Data.ExecutionPayload.FeeRecipient,
 			name:     "ExecPayloadResponse.ExecutionPayload.FeeRecipient",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ExecutionPayload.StateRoot),
+			actual:   epr.Data.ExecutionPayload.StateRoot,
 			name:     "ExecPayloadResponse.ExecutionPayload.StateRoot",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ExecutionPayload.ReceiptsRoot),
+			actual:   epr.Data.ExecutionPayload.ReceiptsRoot,
 			name:     "ExecPayloadResponse.ExecutionPayload.ReceiptsRoot",
 		},
 		{
 			expected: "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
-			actual:   hexutil.Encode(epr.Data.ExecutionPayload.LogsBloom),
+			actual:   epr.Data.ExecutionPayload.LogsBloom,
 			name:     "ExecPayloadResponse.ExecutionPayload.LogsBloom",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ExecutionPayload.PrevRandao),
+			actual:   epr.Data.ExecutionPayload.PrevRandao,
 			name:     "ExecPayloadResponse.ExecutionPayload.PrevRandao",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.ExecutionPayload.BlockNumber),
+			actual:   epr.Data.ExecutionPayload.BlockNumber,
 			name:     "ExecPayloadResponse.ExecutionPayload.BlockNumber",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.ExecutionPayload.GasLimit),
+			actual:   epr.Data.ExecutionPayload.GasLimit,
 			name:     "ExecPayloadResponse.ExecutionPayload.GasLimit",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.ExecutionPayload.GasUsed),
+			actual:   epr.Data.ExecutionPayload.GasUsed,
 			name:     "ExecPayloadResponse.ExecutionPayload.GasUsed",
 		},
 		{
 			expected: "1",
-			actual:   fmt.Sprintf("%d", epr.Data.ExecutionPayload.Timestamp),
+			actual:   epr.Data.ExecutionPayload.Timestamp,
 			name:     "ExecPayloadResponse.ExecutionPayload.Timestamp",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ExecutionPayload.ExtraData),
+			actual:   epr.Data.ExecutionPayload.ExtraData,
 			name:     "ExecPayloadResponse.ExecutionPayload.ExtraData",
 		},
 		{
 			expected: "452312848583266388373324160190187140051835877600158453279131187530910662656",
-			actual:   fmt.Sprintf("%d", epr.Data.ExecutionPayload.BaseFeePerGas),
+			actual:   epr.Data.ExecutionPayload.BaseFeePerGas,
 			name:     "ExecPayloadResponse.ExecutionPayload.BaseFeePerGas",
 		},
 		{
 			expected: "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2",
-			actual:   hexutil.Encode(epr.Data.ExecutionPayload.BlockHash),
+			actual:   epr.Data.ExecutionPayload.BlockHash,
 			name:     "ExecPayloadResponse.ExecutionPayload.BlockHash",
 		},
 		{
 			expected: "2",
-			actual:   fmt.Sprintf("%d", epr.Data.ExecutionPayload.BlobGasUsed),
+			actual:   epr.Data.ExecutionPayload.BlobGasUsed,
 			name:     "ExecPayloadResponse.ExecutionPayload.BlobGasUsed",
 		},
 		{
 			expected: "3",
-			actual:   fmt.Sprintf("%d", epr.Data.ExecutionPayload.ExcessBlobGas),
+			actual:   epr.Data.ExecutionPayload.ExcessBlobGas,
 			name:     "ExecPayloadResponse.ExecutionPayload.ExcessBlobGas",
 		},
 	}
@@ -1069,64 +1045,16 @@ func TestExecutionPayloadResponseDenebUnmarshal(t *testing.T) {
 	}
 	require.Equal(t, 1, len(epr.Data.ExecutionPayload.Transactions))
 	txHash := "0x02f878831469668303f51d843b9ac9f9843b9aca0082520894c93269b73096998db66be0441e836d873535cb9c8894a19041886f000080c001a031cc29234036afbf9a1fb9476b463367cb1f957ac0b919b69bbc798436e604aaa018c4e9c3914eb27aadd0b91e10b18655739fcf8c1fc398763a9f1beecb8ddc86"
-	require.Equal(t, txHash, hexutil.Encode(epr.Data.ExecutionPayload.Transactions[0]))
+	require.Equal(t, txHash, epr.Data.ExecutionPayload.Transactions[0])
 
 	require.Equal(t, 1, len(epr.Data.ExecutionPayload.Withdrawals))
 	w := epr.Data.ExecutionPayload.Withdrawals[0]
-	assert.Equal(t, uint64(1), w.Index.Uint64())
-	assert.Equal(t, uint64(1), w.ValidatorIndex.Uint64())
-	assert.DeepEqual(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943", w.Address.String())
-	assert.Equal(t, uint64(1), w.Amount.Uint64())
-	assert.Equal(t, uint64(2), uint64(epr.Data.ExecutionPayload.BlobGasUsed))
-	assert.Equal(t, uint64(3), uint64(epr.Data.ExecutionPayload.ExcessBlobGas))
-}
-
-func TestExecutionPayloadResponseToProto(t *testing.T) {
-	hr := &ExecPayloadResponse{}
-	require.NoError(t, json.Unmarshal([]byte(testExampleExecutionPayload), hr))
-	p, err := hr.ToProto()
-	require.NoError(t, err)
-
-	parentHash, err := hexutil.Decode("0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
-	require.NoError(t, err)
-	feeRecipient, err := hexutil.Decode("0xabcf8e0d4e9587369b2301d0790347320302cc09")
-	require.NoError(t, err)
-	stateRoot, err := hexutil.Decode("0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
-	require.NoError(t, err)
-	receiptsRoot, err := hexutil.Decode("0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
-	require.NoError(t, err)
-	logsBloom, err := hexutil.Decode("0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000")
-	require.NoError(t, err)
-	prevRandao, err := hexutil.Decode("0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
-	require.NoError(t, err)
-	extraData, err := hexutil.Decode("0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
-	require.NoError(t, err)
-	blockHash, err := hexutil.Decode("0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
-	require.NoError(t, err)
-
-	tx, err := hexutil.Decode("0x02f878831469668303f51d843b9ac9f9843b9aca0082520894c93269b73096998db66be0441e836d873535cb9c8894a19041886f000080c001a031cc29234036afbf9a1fb9476b463367cb1f957ac0b919b69bbc798436e604aaa018c4e9c3914eb27aadd0b91e10b18655739fcf8c1fc398763a9f1beecb8ddc86")
-	require.NoError(t, err)
-	txList := [][]byte{tx}
-
-	bfpg, err := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
-	require.NoError(t, err)
-	expected := &v1.ExecutionPayload{
-		ParentHash:    parentHash,
-		FeeRecipient:  feeRecipient,
-		StateRoot:     stateRoot,
-		ReceiptsRoot:  receiptsRoot,
-		LogsBloom:     logsBloom,
-		PrevRandao:    prevRandao,
-		BlockNumber:   1,
-		GasLimit:      1,
-		GasUsed:       1,
-		Timestamp:     1,
-		ExtraData:     extraData,
-		BaseFeePerGas: bfpg.SSZBytes(),
-		BlockHash:     blockHash,
-		Transactions:  txList,
-	}
-	require.DeepEqual(t, expected, p)
+	assert.Equal(t, "1", w.WithdrawalIndex)
+	assert.Equal(t, "1", w.ValidatorIndex)
+	assert.DeepEqual(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943", w.ExecutionAddress)
+	assert.Equal(t, "1", w.Amount)
+	assert.Equal(t, "2", epr.Data.ExecutionPayload.BlobGasUsed)
+	assert.Equal(t, "3", epr.Data.ExecutionPayload.ExcessBlobGas)
 }
 
 func TestExecutionPayloadResponseCapellaToProto(t *testing.T) {
@@ -1294,16 +1222,6 @@ func pbEth1Data() *eth.Eth1Data {
 	}
 }
 
-func TestEth1DataMarshal(t *testing.T) {
-	ed := &Eth1Data{
-		Eth1Data: pbEth1Data(),
-	}
-	b, err := json.Marshal(ed)
-	require.NoError(t, err)
-	expected := `{"deposit_root":"0x0000000000000000000000000000000000000000000000000000000000000000","deposit_count":"23","block_hash":"0x0000000000000000000000000000000000000000000000000000000000000000"}`
-	require.Equal(t, expected, string(b))
-}
-
 func pbSyncAggregate() *eth.SyncAggregate {
 	return &eth.SyncAggregate{
 		SyncCommitteeSignature: make([]byte, 48),
@@ -1311,14 +1229,6 @@ func pbSyncAggregate() *eth.SyncAggregate {
 	}
 }
 
-func TestSyncAggregate_MarshalJSON(t *testing.T) {
-	sa := &SyncAggregate{pbSyncAggregate()}
-	b, err := json.Marshal(sa)
-	require.NoError(t, err)
-	expected := `{"sync_committee_bits":"0x01","sync_committee_signature":"0x000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"}`
-	require.Equal(t, expected, string(b))
-}
-
 func pbDeposit(t *testing.T) *eth.Deposit {
 	return &eth.Deposit{
 		Proof: [][]byte{ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")},
@@ -1331,16 +1241,6 @@ func pbDeposit(t *testing.T) *eth.Deposit {
 	}
 }
 
-func TestDeposit_MarshalJSON(t *testing.T) {
-	d := &Deposit{
-		Deposit: pbDeposit(t),
-	}
-	b, err := json.Marshal(d)
-	require.NoError(t, err)
-	expected := `{"proof":["0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"],"data":{"pubkey":"0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a","withdrawal_credentials":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","amount":"1","signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}}`
-	require.Equal(t, expected, string(b))
-}
-
 func pbSignedVoluntaryExit(t *testing.T) *eth.SignedVoluntaryExit {
 	return &eth.SignedVoluntaryExit{
 		Exit: &eth.VoluntaryExit{
@@ -1351,16 +1251,6 @@ func pbSignedVoluntaryExit(t *testing.T) *eth.SignedVoluntaryExit {
 	}
 }
 
-func TestVoluntaryExit(t *testing.T) {
-	ve := &SignedVoluntaryExit{
-		SignedVoluntaryExit: pbSignedVoluntaryExit(t),
-	}
-	b, err := json.Marshal(ve)
-	require.NoError(t, err)
-	expected := `{"message":{"epoch":"1","validator_index":"1"},"signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}`
-	require.Equal(t, expected, string(b))
-}
-
 func pbAttestation(t *testing.T) *eth.Attestation {
 	return &eth.Attestation{
 		AggregationBits: bitfield.Bitlist{0x01},
@@ -1381,16 +1271,6 @@ func pbAttestation(t *testing.T) *eth.Attestation {
 	}
 }
 
-func TestAttestationMarshal(t *testing.T) {
-	a := &Attestation{
-		Attestation: pbAttestation(t),
-	}
-	b, err := json.Marshal(a)
-	require.NoError(t, err)
-	expected := `{"aggregation_bits":"0x01","data":{"slot":"1","index":"1","beacon_block_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","source":{"epoch":"1","root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"},"target":{"epoch":"1","root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}},"signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}`
-	require.Equal(t, expected, string(b))
-}
-
 func pbAttesterSlashing(t *testing.T) *eth.AttesterSlashing {
 	return &eth.AttesterSlashing{
 		Attestation_1: &eth.IndexedAttestation{
@@ -1431,9 +1311,7 @@ func pbAttesterSlashing(t *testing.T) *eth.AttesterSlashing {
 }
 
 func TestAttesterSlashing_MarshalJSON(t *testing.T) {
-	as := &AttesterSlashing{
-		AttesterSlashing: pbAttesterSlashing(t),
-	}
+	as := structs.AttesterSlashingFromConsensus(pbAttesterSlashing(t))
 	b, err := json.Marshal(as)
 	require.NoError(t, err)
 	expected := `{"attestation_1":{"attesting_indices":["1"],"data":{"slot":"1","index":"1","beacon_block_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","source":{"epoch":"1","root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"},"target":{"epoch":"1","root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}},"signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"},"attestation_2":{"attesting_indices":["1"],"data":{"slot":"1","index":"1","beacon_block_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","source":{"epoch":"1","root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"},"target":{"epoch":"1","root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}},"signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}}`
@@ -1541,9 +1419,8 @@ func pbExecutionPayloadHeaderDeneb(t *testing.T) *v1.ExecutionPayloadHeaderDeneb
 }
 
 func TestExecutionPayloadHeader_MarshalJSON(t *testing.T) {
-	h := &ExecutionPayloadHeader{
-		ExecutionPayloadHeader: pbExecutionPayloadHeader(t),
-	}
+	h, err := structs.ExecutionPayloadHeaderFromConsensus(pbExecutionPayloadHeader(t))
+	require.NoError(t, err)
 	b, err := json.Marshal(h)
 	require.NoError(t, err)
 	expected := `{"parent_hash":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","fee_recipient":"0xabcf8e0d4e9587369b2301d0790347320302cc09","state_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","receipts_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","logs_bloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","prev_randao":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","block_number":"1","gas_limit":"1","gas_used":"1","timestamp":"1","extra_data":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","base_fee_per_gas":"452312848583266388373324160190187140051835877600158453279131187530910662656","block_hash":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","transactions_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}`
@@ -1551,9 +1428,9 @@ func TestExecutionPayloadHeader_MarshalJSON(t *testing.T) {
 }
 
 func TestExecutionPayloadHeaderCapella_MarshalJSON(t *testing.T) {
-	h := &ExecutionPayloadHeaderCapella{
-		ExecutionPayloadHeaderCapella: pbExecutionPayloadHeaderCapella(t),
-	}
+	h, err := structs.ExecutionPayloadHeaderCapellaFromConsensus(pbExecutionPayloadHeaderCapella(t))
+	require.NoError(t, err)
+	require.NoError(t, err)
 	b, err := json.Marshal(h)
 	require.NoError(t, err)
 	expected := `{"parent_hash":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","fee_recipient":"0xabcf8e0d4e9587369b2301d0790347320302cc09","state_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","receipts_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","logs_bloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","prev_randao":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","block_number":"1","gas_limit":"1","gas_used":"1","timestamp":"1","extra_data":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","base_fee_per_gas":"452312848583266388373324160190187140051835877600158453279131187530910662656","block_hash":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","transactions_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","withdrawals_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}`
@@ -1561,9 +1438,8 @@ func TestExecutionPayloadHeaderCapella_MarshalJSON(t *testing.T) {
 }
 
 func TestExecutionPayloadHeaderDeneb_MarshalJSON(t *testing.T) {
-	h := &ExecutionPayloadHeaderDeneb{
-		ExecutionPayloadHeaderDeneb: pbExecutionPayloadHeaderDeneb(t),
-	}
+	h, err := structs.ExecutionPayloadHeaderDenebFromConsensus(pbExecutionPayloadHeaderDeneb(t))
+	require.NoError(t, err)
 	b, err := json.Marshal(h)
 	require.NoError(t, err)
 	expected := `{"parent_hash":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","fee_recipient":"0xabcf8e0d4e9587369b2301d0790347320302cc09","state_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","receipts_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","logs_bloom":"0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000","prev_randao":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","block_number":"1","gas_limit":"1","gas_used":"1","timestamp":"1","extra_data":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","base_fee_per_gas":"452312848583266388373324160190187140051835877600158453279131187530910662656","block_hash":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","transactions_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","withdrawals_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2","blob_gas_used":"1","excess_blob_gas":"2"}`
@@ -1792,12 +1668,13 @@ func TestRoundTripUint256(t *testing.T) {
 func TestRoundTripProtoUint256(t *testing.T) {
 	h := pbExecutionPayloadHeader(t)
 	h.BaseFeePerGas = []byte{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31}
-	hm := &ExecutionPayloadHeader{ExecutionPayloadHeader: h}
+	hm, err := structs.ExecutionPayloadHeaderFromConsensus(h)
+	require.NoError(t, err)
 	m, err := json.Marshal(hm)
 	require.NoError(t, err)
-	hu := &ExecutionPayloadHeader{}
+	hu := &structs.ExecutionPayloadHeader{}
 	require.NoError(t, json.Unmarshal(m, hu))
-	hp, err := hu.ToProto()
+	hp, err := hu.ToConsensus()
 	require.NoError(t, err)
 	require.DeepEqual(t, h.BaseFeePerGas, hp.BaseFeePerGas)
 }
@@ -1805,7 +1682,7 @@ func TestRoundTripProtoUint256(t *testing.T) {
 func TestExecutionPayloadHeaderRoundtrip(t *testing.T) {
 	expected, err := os.ReadFile("testdata/execution-payload.json")
 	require.NoError(t, err)
-	hu := &ExecutionPayloadHeader{}
+	hu := &structs.ExecutionPayloadHeader{}
 	require.NoError(t, json.Unmarshal(expected, hu))
 	m, err := json.Marshal(hu)
 	require.NoError(t, err)
@@ -1815,14 +1692,14 @@ func TestExecutionPayloadHeaderRoundtrip(t *testing.T) {
 func TestExecutionPayloadHeaderCapellaRoundtrip(t *testing.T) {
 	expected, err := os.ReadFile("testdata/execution-payload-capella.json")
 	require.NoError(t, err)
-	hu := &ExecutionPayloadHeaderCapella{}
+	hu := &structs.ExecutionPayloadHeaderCapella{}
 	require.NoError(t, json.Unmarshal(expected, hu))
 	m, err := json.Marshal(hu)
 	require.NoError(t, err)
 	require.DeepEqual(t, string(expected[0:len(expected)-1]), string(m))
 }
 
-func TestErrorMessage_non200Err(t *testing.T) {
+func TestErrorMessage_unexpectedStatusErr(t *testing.T) {
 	mockRequest := &http.Request{
 		URL: &url.URL{Path: "example.com"},
 	}
@@ -1902,7 +1779,7 @@ func TestErrorMessage_non200Err(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			err := non200Err(tt.args)
+			err := unexpectedStatusErr(tt.args, http.StatusOK)
 			if err != nil && tt.wantMessage != "" {
 				require.ErrorContains(t, tt.wantMessage, err)
 			}
@@ -1924,9 +1801,9 @@ func TestEmptyResponseBody(t *testing.T) {
 		emptyResponse := &ExecutionPayloadResponse{}
 		require.NoError(t, json.Unmarshal(empty, emptyResponse))
 		_, err := emptyResponse.ParsePayload()
-		require.ErrorIs(t, err, consensusblocks.ErrUnsupportedVersion)
+		require.ErrorContains(t, "unsupported version", err)
 	})
-	versions := []int{version.Bellatrix, version.Capella, version.Deneb}
+	versions := []int{version.Bellatrix, version.Capella, version.Deneb, version.Electra}
 	for i := range versions {
 		vstr := version.String(versions[i])
 		t.Run("populated version without payload"+vstr, func(t *testing.T) {
@@ -1936,11 +1813,9 @@ func TestEmptyResponseBody(t *testing.T) {
 			epr := &ExecutionPayloadResponse{}
 			require.NoError(t, json.Unmarshal(encoded, epr))
 			pp, err := epr.ParsePayload()
-			require.NoError(t, err)
-			pb, err := pp.PayloadProto()
 			if err == nil {
 				require.NoError(t, err)
-				require.Equal(t, false, pb == nil)
+				require.Equal(t, false, pp == nil)
 			} else {
 				require.ErrorIs(t, err, consensusblocks.ErrNilObject)
 			}

api/client/client.go

@@ -10,11 +10,18 @@ import (
 	"github.com/pkg/errors"
 )
 
+const (
+	MaxBodySize      int64 = 1 << 23 // 8MB default, WithMaxBodySize can override
+	MaxBodySizeState int64 = 1 << 29 // 512MB
+	MaxErrBodySize   int64 = 1 << 17 // 128KB
+)
+
 // Client is a wrapper object around the HTTP client.
 type Client struct {
-	hc      *http.Client
-	baseURL *url.URL
-	token   string
+	hc          *http.Client
+	baseURL     *url.URL
+	token       string
+	maxBodySize int64
 }
 
 // NewClient constructs a new client with the provided options (ex WithTimeout).
@@ -26,8 +33,9 @@ func NewClient(host string, opts ...ClientOpt) (*Client, error) {
 		return nil, err
 	}
 	c := &Client{
-		hc:      &http.Client{},
-		baseURL: u,
+		hc:          &http.Client{},
+		baseURL:     u,
+		maxBodySize: MaxBodySize,
 	}
 	for _, o := range opts {
 		o(c)
@@ -72,7 +80,7 @@ func (c *Client) NodeURL() string {
 // Get is a generic, opinionated GET function to reduce boilerplate amongst the getters in this package.
 func (c *Client) Get(ctx context.Context, path string, opts ...ReqOption) ([]byte, error) {
 	u := c.baseURL.ResolveReference(&url.URL{Path: path})
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), nil)
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), http.NoBody)
 	if err != nil {
 		return nil, err
 	}
@@ -89,7 +97,7 @@ func (c *Client) Get(ctx context.Context, path string, opts ...ReqOption) ([]byt
 	if r.StatusCode != http.StatusOK {
 		return nil, Non200Err(r)
 	}
-	b, err := io.ReadAll(r.Body)
+	b, err := io.ReadAll(io.LimitReader(r.Body, c.maxBodySize))
 	if err != nil {
 		return nil, errors.Wrap(err, "error reading http response body")
 	}

api/client/client_test.go

@@ -4,7 +4,7 @@ import (
 	"net/url"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 )
 
 func TestValidHostname(t *testing.T) {

api/client/errors.go

@@ -25,16 +25,16 @@ var ErrInvalidNodeVersion = errors.New("invalid node version response")
 var ErrConnectionIssue = errors.New("could not connect")
 
 // Non200Err is a function that parses an HTTP response to handle responses that are not 200 with a formatted error.
-func Non200Err(response *http.Response) error {
-	bodyBytes, err := io.ReadAll(response.Body)
+func Non200Err(r *http.Response) error {
+	b, err := io.ReadAll(io.LimitReader(r.Body, MaxErrBodySize))
 	var body string
 	if err != nil {
 		body = "(Unable to read response body.)"
 	} else {
-		body = "response body:\n" + string(bodyBytes)
+		body = "response body:\n" + string(b)
 	}
-	msg := fmt.Sprintf("code=%d, url=%s, body=%s", response.StatusCode, response.Request.URL, body)
-	switch response.StatusCode {
+	msg := fmt.Sprintf("code=%d, url=%s, body=%s", r.StatusCode, r.Request.URL, body)
+	switch r.StatusCode {
 	case http.StatusNotFound:
 		return errors.Wrap(ErrNotFound, msg)
 	default:

api/client/event/BUILD.bazel

@@ -6,7 +6,7 @@ go_library(
         "event_stream.go",
         "utils.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/event",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/client/event",
     visibility = ["//visibility:public"],
     deps = [
         "//api:go_default_library",

api/client/event/event_stream.go

@@ -7,29 +7,17 @@ import (
 	"net/url"
 	"strings"
 
+	"github.com/OffchainLabs/prysm/v6/api"
+	"github.com/OffchainLabs/prysm/v6/api/client"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/api"
-	"github.com/prysmaticlabs/prysm/v5/api/client"
 	log "github.com/sirupsen/logrus"
 )
 
 const (
-	EventHead                        = "head"
-	EventBlock                       = "block"
-	EventAttestation                 = "attestation"
-	EventVoluntaryExit               = "voluntary_exit"
-	EventBlsToExecutionChange        = "bls_to_execution_change"
-	EventProposerSlashing            = "proposer_slashing"
-	EventAttesterSlashing            = "attester_slashing"
-	EventFinalizedCheckpoint         = "finalized_checkpoint"
-	EventChainReorg                  = "chain_reorg"
-	EventContributionAndProof        = "contribution_and_proof"
-	EventLightClientFinalityUpdate   = "light_client_finality_update"
-	EventLightClientOptimisticUpdate = "light_client_optimistic_update"
-	EventPayloadAttributes           = "payload_attributes"
-	EventBlobSidecar                 = "blob_sidecar"
-	EventError                       = "error"
-	EventConnectionError             = "connection_error"
+	EventHead = "head"
+
+	EventError           = "error"
+	EventConnectionError = "connection_error"
 )
 
 var (
@@ -93,6 +81,7 @@ func (h *EventStream) Subscribe(eventsChannel chan<- *Event) {
 			EventType: EventConnectionError,
 			Data:      []byte(errors.Wrap(err, client.ErrConnectionIssue.Error()).Error()),
 		}
+		return
 	}
 
 	defer func() {

api/client/event/event_stream_test.go

@@ -1,14 +1,13 @@
 package event
 
 import (
-	"context"
 	"fmt"
 	"net/http"
 	"net/http/httptest"
 	"testing"
 	"time"
 
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 	log "github.com/sirupsen/logrus"
 )
 
@@ -30,7 +29,7 @@ func TestNewEventStream(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			_, err := NewEventStream(context.Background(), &http.Client{}, tt.host, tt.topics)
+			_, err := NewEventStream(t.Context(), &http.Client{}, tt.host, tt.topics)
 			if (err != nil) != tt.wantErr {
 				t.Errorf("NewEventStream() error = %v, wantErr %v", err, tt.wantErr)
 			}
@@ -40,7 +39,7 @@ func TestNewEventStream(t *testing.T) {
 
 func TestEventStream(t *testing.T) {
 	mux := http.NewServeMux()
-	mux.HandleFunc("/eth/v1/events", func(w http.ResponseWriter, r *http.Request) {
+	mux.HandleFunc("/eth/v1/events", func(w http.ResponseWriter, _ *http.Request) {
 		flusher, ok := w.(http.Flusher)
 		require.Equal(t, true, ok)
 		for i := 1; i <= 3; i++ {
@@ -56,7 +55,7 @@ func TestEventStream(t *testing.T) {
 
 	topics := []string{"head"}
 	eventsChannel := make(chan *Event, 1)
-	stream, err := NewEventStream(context.Background(), http.DefaultClient, server.URL, topics)
+	stream, err := NewEventStream(t.Context(), http.DefaultClient, server.URL, topics)
 	require.NoError(t, err)
 	go stream.Subscribe(eventsChannel)
 
@@ -79,3 +78,22 @@ func TestEventStream(t *testing.T) {
 		}
 	}
 }
+
+func TestEventStreamRequestError(t *testing.T) {
+	topics := []string{"head"}
+	eventsChannel := make(chan *Event, 1)
+	ctx := t.Context()
+
+	// use valid url that will result in failed request with nil body
+	stream, err := NewEventStream(ctx, http.DefaultClient, "http://badhost:1234", topics)
+	require.NoError(t, err)
+
+	// error will happen when request is made, should be received over events channel
+	go stream.Subscribe(eventsChannel)
+
+	event := <-eventsChannel
+	if event.EventType != EventConnectionError {
+		t.Errorf("Expected event type %q, got %q", EventConnectionError, event.EventType)
+	}
+
+}

api/client/event/utils_test.go

@@ -5,7 +5,7 @@ import (
 	"bytes"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 )
 
 func TestScanLinesWithCarriage(t *testing.T) {

api/client/options.go

@@ -46,3 +46,10 @@ func WithAuthenticationToken(token string) ClientOpt {
 		c.token = token
 	}
 }
+
+// WithMaxBodySize overrides the default max body size of 8MB.
+func WithMaxBodySize(size int64) ClientOpt {
+	return func(c *Client) {
+		c.maxBodySize = size
+	}
+}

api/client/validator/BUILD.bazel

@@ -3,7 +3,7 @@ load("@prysm//tools/go:def.bzl", "go_library")
 go_library(
     name = "go_default_library",
     srcs = ["client.go"],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/validator",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/client/validator",
     visibility = ["//visibility:public"],
     deps = [
         "//api/client:go_default_library",

api/client/validator/client.go

@@ -6,9 +6,9 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/OffchainLabs/prysm/v6/api/client"
+	"github.com/OffchainLabs/prysm/v6/validator/rpc"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/api/client"
-	"github.com/prysmaticlabs/prysm/v5/validator/rpc"
 )
 
 const (

api/gateway/BUILD.bazel

@@ -1,43 +0,0 @@
-load("@prysm//tools/go:def.bzl", "go_library", "go_test")
-
-go_library(
-    name = "go_default_library",
-    srcs = [
-        "gateway.go",
-        "log.go",
-        "modifiers.go",
-        "options.go",
-    ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/gateway",
-    visibility = [
-        "//beacon-chain:__subpackages__",
-        "//validator:__subpackages__",
-    ],
-    deps = [
-        "//api/server/middleware:go_default_library",
-        "//runtime:go_default_library",
-        "@com_github_gorilla_mux//:go_default_library",
-        "@com_github_grpc_ecosystem_grpc_gateway_v2//runtime:go_default_library",
-        "@com_github_pkg_errors//:go_default_library",
-        "@com_github_sirupsen_logrus//:go_default_library",
-        "@org_golang_google_grpc//:go_default_library",
-        "@org_golang_google_grpc//connectivity:go_default_library",
-        "@org_golang_google_grpc//credentials:go_default_library",
-        "@org_golang_google_grpc//credentials/insecure:go_default_library",
-        "@org_golang_google_protobuf//proto:go_default_library",
-    ],
-)
-
-go_test(
-    name = "go_default_test",
-    srcs = ["gateway_test.go"],
-    embed = [":go_default_library"],
-    deps = [
-        "//cmd/beacon-chain/flags:go_default_library",
-        "//testing/assert:go_default_library",
-        "//testing/require:go_default_library",
-        "@com_github_gorilla_mux//:go_default_library",
-        "@com_github_sirupsen_logrus//hooks/test:go_default_library",
-        "@com_github_urfave_cli_v2//:go_default_library",
-    ],
-)

api/gateway/gateway.go

@@ -1,212 +0,0 @@
-// Package gateway defines a grpc-gateway server that serves HTTP-JSON traffic and acts a proxy between HTTP and gRPC.
-package gateway
-
-import (
-	"context"
-	"fmt"
-	"net"
-	"net/http"
-	"time"
-
-	"github.com/gorilla/mux"
-	gwruntime "github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
-	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/api/server/middleware"
-	"github.com/prysmaticlabs/prysm/v5/runtime"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/connectivity"
-	"google.golang.org/grpc/credentials"
-	"google.golang.org/grpc/credentials/insecure"
-)
-
-var _ runtime.Service = (*Gateway)(nil)
-
-// PbMux serves grpc-gateway requests for selected patterns using registered protobuf handlers.
-type PbMux struct {
-	Registrations []PbHandlerRegistration // Protobuf registrations to be registered in Mux.
-	Patterns      []string                // URL patterns that will be handled by Mux.
-	Mux           *gwruntime.ServeMux     // The router that will be used for grpc-gateway requests.
-}
-
-// PbHandlerRegistration is a function that registers a protobuf handler.
-type PbHandlerRegistration func(context.Context, *gwruntime.ServeMux, *grpc.ClientConn) error
-
-// MuxHandler is a function that implements the mux handler functionality.
-type MuxHandler func(
-	h http.HandlerFunc,
-	w http.ResponseWriter,
-	req *http.Request,
-)
-
-// Config parameters for setting up the gateway service.
-type config struct {
-	maxCallRecvMsgSize uint64
-	remoteCert         string
-	gatewayAddr        string
-	remoteAddr         string
-	allowedOrigins     []string
-	muxHandler         MuxHandler
-	pbHandlers         []*PbMux
-	router             *mux.Router
-	timeout            time.Duration
-}
-
-// Gateway is the gRPC gateway to serve HTTP JSON traffic as a proxy and forward it to the gRPC server.
-type Gateway struct {
-	cfg          *config
-	conn         *grpc.ClientConn
-	server       *http.Server
-	cancel       context.CancelFunc
-	ctx          context.Context
-	startFailure error
-}
-
-// New returns a new instance of the Gateway.
-func New(ctx context.Context, opts ...Option) (*Gateway, error) {
-	g := &Gateway{
-		ctx: ctx,
-		cfg: &config{},
-	}
-	for _, opt := range opts {
-		if err := opt(g); err != nil {
-			return nil, err
-		}
-	}
-	if g.cfg.router == nil {
-		g.cfg.router = mux.NewRouter()
-	}
-	return g, nil
-}
-
-// Start the gateway service.
-func (g *Gateway) Start() {
-	ctx, cancel := context.WithCancel(g.ctx)
-	g.cancel = cancel
-
-	conn, err := g.dial(ctx, "tcp", g.cfg.remoteAddr)
-	if err != nil {
-		log.WithError(err).Error("Failed to connect to gRPC server")
-		g.startFailure = err
-		return
-	}
-	g.conn = conn
-
-	for _, h := range g.cfg.pbHandlers {
-		for _, r := range h.Registrations {
-			if err := r(ctx, h.Mux, g.conn); err != nil {
-				log.WithError(err).Error("Failed to register handler")
-				g.startFailure = err
-				return
-			}
-		}
-		for _, p := range h.Patterns {
-			g.cfg.router.PathPrefix(p).Handler(h.Mux)
-		}
-	}
-
-	corsMux := middleware.CorsHandler(g.cfg.allowedOrigins).Middleware(g.cfg.router)
-
-	if g.cfg.muxHandler != nil {
-		g.cfg.router.PathPrefix("/").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			g.cfg.muxHandler(corsMux.ServeHTTP, w, r)
-		})
-	}
-
-	g.server = &http.Server{
-		Addr:              g.cfg.gatewayAddr,
-		Handler:           corsMux,
-		ReadHeaderTimeout: time.Second,
-	}
-
-	go func() {
-		log.WithField("address", g.cfg.gatewayAddr).Info("Starting gRPC gateway")
-		if err := g.server.ListenAndServe(); err != http.ErrServerClosed {
-			log.WithError(err).Error("Failed to start gRPC gateway")
-			g.startFailure = err
-			return
-		}
-	}()
-}
-
-// Status of grpc gateway. Returns an error if this service is unhealthy.
-func (g *Gateway) Status() error {
-	if g.startFailure != nil {
-		return g.startFailure
-	}
-	if s := g.conn.GetState(); s != connectivity.Ready {
-		return fmt.Errorf("grpc server is %s", s)
-	}
-	return nil
-}
-
-// Stop the gateway with a graceful shutdown.
-func (g *Gateway) Stop() error {
-	if g.server != nil {
-		shutdownCtx, shutdownCancel := context.WithTimeout(g.ctx, 2*time.Second)
-		defer shutdownCancel()
-		if err := g.server.Shutdown(shutdownCtx); err != nil {
-			if errors.Is(err, context.DeadlineExceeded) {
-				log.Warn("Existing connections terminated")
-			} else {
-				log.WithError(err).Error("Failed to gracefully shut down server")
-			}
-		}
-	}
-	if g.cancel != nil {
-		g.cancel()
-	}
-	return nil
-}
-
-// dial the gRPC server.
-func (g *Gateway) dial(ctx context.Context, network, addr string) (*grpc.ClientConn, error) {
-	switch network {
-	case "tcp":
-		return g.dialTCP(ctx, addr)
-	case "unix":
-		return g.dialUnix(ctx, addr)
-	default:
-		return nil, fmt.Errorf("unsupported network type %q", network)
-	}
-}
-
-// dialTCP creates a client connection via TCP.
-// "addr" must be a valid TCP address with a port number.
-func (g *Gateway) dialTCP(ctx context.Context, addr string) (*grpc.ClientConn, error) {
-	var security grpc.DialOption
-	if len(g.cfg.remoteCert) > 0 {
-		creds, err := credentials.NewClientTLSFromFile(g.cfg.remoteCert, "")
-		if err != nil {
-			return nil, err
-		}
-		security = grpc.WithTransportCredentials(creds)
-	} else {
-		// Use insecure credentials when there's no remote cert provided.
-		security = grpc.WithTransportCredentials(insecure.NewCredentials())
-	}
-	opts := []grpc.DialOption{
-		security,
-		grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(int(g.cfg.maxCallRecvMsgSize))),
-	}
-	return grpc.DialContext(ctx, addr, opts...)
-}
-
-// dialUnix creates a client connection via a unix domain socket.
-// "addr" must be a valid path to the socket.
-func (g *Gateway) dialUnix(ctx context.Context, addr string) (*grpc.ClientConn, error) {
-	d := func(addr string, timeout time.Duration) (net.Conn, error) {
-		return net.DialTimeout("unix", addr, timeout)
-	}
-	f := func(ctx context.Context, addr string) (net.Conn, error) {
-		if deadline, ok := ctx.Deadline(); ok {
-			return d(addr, time.Until(deadline))
-		}
-		return d(addr, 0)
-	}
-	opts := []grpc.DialOption{
-		grpc.WithTransportCredentials(insecure.NewCredentials()),
-		grpc.WithContextDialer(f),
-		grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(int(g.cfg.maxCallRecvMsgSize))),
-	}
-	return grpc.DialContext(ctx, addr, opts...)
-}

api/gateway/gateway_test.go

@@ -1,107 +0,0 @@
-package gateway
-
-import (
-	"context"
-	"flag"
-	"fmt"
-	"net/http"
-	"net/http/httptest"
-	"net/url"
-	"testing"
-
-	"github.com/gorilla/mux"
-	"github.com/prysmaticlabs/prysm/v5/cmd/beacon-chain/flags"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
-	logTest "github.com/sirupsen/logrus/hooks/test"
-	"github.com/urfave/cli/v2"
-)
-
-func TestGateway_Customized(t *testing.T) {
-	r := mux.NewRouter()
-	cert := "cert"
-	origins := []string{"origin"}
-	size := uint64(100)
-
-	opts := []Option{
-		WithRouter(r),
-		WithRemoteCert(cert),
-		WithAllowedOrigins(origins),
-		WithMaxCallRecvMsgSize(size),
-		WithMuxHandler(func(
-			_ http.HandlerFunc,
-			_ http.ResponseWriter,
-			_ *http.Request,
-		) {
-		}),
-	}
-
-	g, err := New(context.Background(), opts...)
-	require.NoError(t, err)
-
-	assert.Equal(t, r, g.cfg.router)
-	assert.Equal(t, cert, g.cfg.remoteCert)
-	require.Equal(t, 1, len(g.cfg.allowedOrigins))
-	assert.Equal(t, origins[0], g.cfg.allowedOrigins[0])
-	assert.Equal(t, size, g.cfg.maxCallRecvMsgSize)
-}
-
-func TestGateway_StartStop(t *testing.T) {
-	hook := logTest.NewGlobal()
-
-	app := cli.App{}
-	set := flag.NewFlagSet("test", 0)
-	ctx := cli.NewContext(&app, set, nil)
-
-	gatewayPort := ctx.Int(flags.GRPCGatewayPort.Name)
-	gatewayHost := ctx.String(flags.GRPCGatewayHost.Name)
-	rpcHost := ctx.String(flags.RPCHost.Name)
-	selfAddress := fmt.Sprintf("%s:%d", rpcHost, ctx.Int(flags.RPCPort.Name))
-	gatewayAddress := fmt.Sprintf("%s:%d", gatewayHost, gatewayPort)
-
-	opts := []Option{
-		WithGatewayAddr(gatewayAddress),
-		WithRemoteAddr(selfAddress),
-		WithMuxHandler(func(
-			_ http.HandlerFunc,
-			_ http.ResponseWriter,
-			_ *http.Request,
-		) {
-		}),
-	}
-
-	g, err := New(context.Background(), opts...)
-	require.NoError(t, err)
-
-	g.Start()
-	go func() {
-		require.LogsContain(t, hook, "Starting gRPC gateway")
-		require.LogsDoNotContain(t, hook, "Starting API middleware")
-	}()
-	err = g.Stop()
-	require.NoError(t, err)
-}
-
-func TestGateway_NilHandler_NotFoundHandlerRegistered(t *testing.T) {
-	app := cli.App{}
-	set := flag.NewFlagSet("test", 0)
-	ctx := cli.NewContext(&app, set, nil)
-
-	gatewayPort := ctx.Int(flags.GRPCGatewayPort.Name)
-	gatewayHost := ctx.String(flags.GRPCGatewayHost.Name)
-	rpcHost := ctx.String(flags.RPCHost.Name)
-	selfAddress := fmt.Sprintf("%s:%d", rpcHost, ctx.Int(flags.RPCPort.Name))
-	gatewayAddress := fmt.Sprintf("%s:%d", gatewayHost, gatewayPort)
-
-	opts := []Option{
-		WithGatewayAddr(gatewayAddress),
-		WithRemoteAddr(selfAddress),
-	}
-
-	g, err := New(context.Background(), opts...)
-	require.NoError(t, err)
-
-	writer := httptest.NewRecorder()
-	g.cfg.router.ServeHTTP(writer, &http.Request{Method: "GET", Host: "localhost", URL: &url.URL{Path: "/foo"}})
-	assert.Equal(t, http.StatusNotFound, writer.Code)
-}

api/gateway/log.go

@@ -1,5 +0,0 @@
-package gateway
-
-import "github.com/sirupsen/logrus"
-
-var log = logrus.WithField("prefix", "gateway")

api/gateway/modifiers.go

@@ -1,30 +0,0 @@
-package gateway
-
-import (
-	"context"
-	"net/http"
-	"strconv"
-
-	gwruntime "github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
-	"google.golang.org/protobuf/proto"
-)
-
-func HttpResponseModifier(ctx context.Context, w http.ResponseWriter, _ proto.Message) error {
-	md, ok := gwruntime.ServerMetadataFromContext(ctx)
-	if !ok {
-		return nil
-	}
-	// set http status code
-	if vals := md.HeaderMD.Get("x-http-code"); len(vals) > 0 {
-		code, err := strconv.Atoi(vals[0])
-		if err != nil {
-			return err
-		}
-		// delete the headers to not expose any grpc-metadata in http response
-		delete(md.HeaderMD, "x-http-code")
-		delete(w.Header(), "Grpc-Metadata-X-Http-Code")
-		w.WriteHeader(code)
-	}
-
-	return nil
-}

api/gateway/options.go

@@ -1,79 +0,0 @@
-package gateway
-
-import (
-	"time"
-
-	"github.com/gorilla/mux"
-	gwruntime "github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
-)
-
-type Option func(g *Gateway) error
-
-func WithPbHandlers(handlers []*PbMux) Option {
-	return func(g *Gateway) error {
-		g.cfg.pbHandlers = handlers
-		return nil
-	}
-}
-
-func WithMuxHandler(m MuxHandler) Option {
-	return func(g *Gateway) error {
-		g.cfg.muxHandler = m
-		return nil
-	}
-}
-
-func WithGatewayAddr(addr string) Option {
-	return func(g *Gateway) error {
-		g.cfg.gatewayAddr = addr
-		return nil
-	}
-}
-
-func WithRemoteAddr(addr string) Option {
-	return func(g *Gateway) error {
-		g.cfg.remoteAddr = addr
-		return nil
-	}
-}
-
-// WithRouter allows adding a custom mux router to the gateway.
-func WithRouter(r *mux.Router) Option {
-	return func(g *Gateway) error {
-		g.cfg.router = r
-		return nil
-	}
-}
-
-// WithAllowedOrigins allows adding a set of allowed origins to the gateway.
-func WithAllowedOrigins(origins []string) Option {
-	return func(g *Gateway) error {
-		g.cfg.allowedOrigins = origins
-		return nil
-	}
-}
-
-// WithRemoteCert allows adding a custom certificate to the gateway,
-func WithRemoteCert(cert string) Option {
-	return func(g *Gateway) error {
-		g.cfg.remoteCert = cert
-		return nil
-	}
-}
-
-// WithMaxCallRecvMsgSize allows specifying the maximum allowed gRPC message size.
-func WithMaxCallRecvMsgSize(size uint64) Option {
-	return func(g *Gateway) error {
-		g.cfg.maxCallRecvMsgSize = size
-		return nil
-	}
-}
-
-// WithTimeout allows changing the timeout value for API calls.
-func WithTimeout(seconds uint64) Option {
-	return func(g *Gateway) error {
-		g.cfg.timeout = time.Second * time.Duration(seconds)
-		gwruntime.DefaultContextTimeout = time.Second * time.Duration(seconds)
-		return nil
-	}
-}

api/grpc/BUILD.bazel

@@ -6,7 +6,7 @@ go_library(
         "grpcutils.go",
         "parameters.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/grpc",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/grpc",
     visibility = ["//visibility:public"],
     deps = [
         "@com_github_sirupsen_logrus//:go_default_library",
@@ -22,9 +22,7 @@ go_test(
     deps = [
         "//testing/assert:go_default_library",
         "//testing/require:go_default_library",
-        "@com_github_grpc_ecosystem_grpc_gateway_v2//runtime:go_default_library",
         "@com_github_sirupsen_logrus//hooks/test:go_default_library",
-        "@org_golang_google_grpc//:go_default_library",
         "@org_golang_google_grpc//metadata:go_default_library",
     ],
 )

api/grpc/grpcutils.go

@@ -2,8 +2,6 @@ package grpc
 
 import (
 	"context"
-	"encoding/json"
-	"fmt"
 	"strings"
 	"time"
 
@@ -76,21 +74,8 @@ func AppendHeaders(parent context.Context, headers []string) context.Context {
 				logrus.Warnf("Incorrect gRPC header flag format. Skipping %v", keyValue[0])
 				continue
 			}
-			parent = metadata.AppendToOutgoingContext(parent, keyValue[0], strings.Join(keyValue[1:], "="))
+			parent = metadata.AppendToOutgoingContext(parent, keyValue[0], strings.Join(keyValue[1:], "=")) // nolint:fatcontext
 		}
 	}
 	return parent
 }
-
-// AppendCustomErrorHeader sets a CustomErrorMetadataKey gRPC header on the passed in context,
-// using the passed in error data as the header's value. The data is serialized as JSON.
-func AppendCustomErrorHeader(ctx context.Context, errorData interface{}) error {
-	j, err := json.Marshal(errorData)
-	if err != nil {
-		return fmt.Errorf("could not marshal error data into JSON: %w", err)
-	}
-	if err := grpc.SetHeader(ctx, metadata.Pairs(CustomErrorMetadataKey, string(j))); err != nil {
-		return fmt.Errorf("could not set custom error header: %w", err)
-	}
-	return nil
-}

api/grpc/grpcutils_test.go

@@ -1,16 +1,11 @@
 package grpc
 
 import (
-	"context"
-	"encoding/json"
-	"strings"
 	"testing"
 
-	"github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 	logTest "github.com/sirupsen/logrus/hooks/test"
-	"google.golang.org/grpc"
 	"google.golang.org/grpc/metadata"
 )
 
@@ -20,7 +15,7 @@ type customErrorData struct {
 
 func TestAppendHeaders(t *testing.T) {
 	t.Run("one_header", func(t *testing.T) {
-		ctx := AppendHeaders(context.Background(), []string{"first=value1"})
+		ctx := AppendHeaders(t.Context(), []string{"first=value1"})
 		md, ok := metadata.FromOutgoingContext(ctx)
 		require.Equal(t, true, ok, "Failed to read context metadata")
 		require.Equal(t, 1, md.Len(), "MetadataV0 contains wrong number of values")
@@ -28,7 +23,7 @@ func TestAppendHeaders(t *testing.T) {
 	})
 
 	t.Run("multiple_headers", func(t *testing.T) {
-		ctx := AppendHeaders(context.Background(), []string{"first=value1", "second=value2"})
+		ctx := AppendHeaders(t.Context(), []string{"first=value1", "second=value2"})
 		md, ok := metadata.FromOutgoingContext(ctx)
 		require.Equal(t, true, ok, "Failed to read context metadata")
 		require.Equal(t, 2, md.Len(), "MetadataV0 contains wrong number of values")
@@ -37,7 +32,7 @@ func TestAppendHeaders(t *testing.T) {
 	})
 
 	t.Run("one_empty_header", func(t *testing.T) {
-		ctx := AppendHeaders(context.Background(), []string{"first=value1", ""})
+		ctx := AppendHeaders(t.Context(), []string{"first=value1", ""})
 		md, ok := metadata.FromOutgoingContext(ctx)
 		require.Equal(t, true, ok, "Failed to read context metadata")
 		require.Equal(t, 1, md.Len(), "MetadataV0 contains wrong number of values")
@@ -46,7 +41,7 @@ func TestAppendHeaders(t *testing.T) {
 
 	t.Run("incorrect_header", func(t *testing.T) {
 		logHook := logTest.NewGlobal()
-		ctx := AppendHeaders(context.Background(), []string{"first=value1", "second"})
+		ctx := AppendHeaders(t.Context(), []string{"first=value1", "second"})
 		md, ok := metadata.FromOutgoingContext(ctx)
 		require.Equal(t, true, ok, "Failed to read context metadata")
 		require.Equal(t, 1, md.Len(), "MetadataV0 contains wrong number of values")
@@ -55,24 +50,10 @@ func TestAppendHeaders(t *testing.T) {
 	})
 
 	t.Run("header_value_with_equal_sign", func(t *testing.T) {
-		ctx := AppendHeaders(context.Background(), []string{"first=value=1"})
+		ctx := AppendHeaders(t.Context(), []string{"first=value=1"})
 		md, ok := metadata.FromOutgoingContext(ctx)
 		require.Equal(t, true, ok, "Failed to read context metadata")
 		require.Equal(t, 1, md.Len(), "MetadataV0 contains wrong number of values")
 		assert.Equal(t, "value=1", md.Get("first")[0])
 	})
 }
-
-func TestAppendCustomErrorHeader(t *testing.T) {
-	stream := &runtime.ServerTransportStream{}
-	ctx := grpc.NewContextWithServerTransportStream(context.Background(), stream)
-	data := &customErrorData{Message: "foo"}
-	require.NoError(t, AppendCustomErrorHeader(ctx, data))
-	// The stream used in test setup sets the metadata key in lowercase.
-	value, ok := stream.Header()[strings.ToLower(CustomErrorMetadataKey)]
-	require.Equal(t, true, ok, "Failed to retrieve custom error metadata value")
-	expected, err := json.Marshal(data)
-	require.NoError(t, err)
-	assert.Equal(t, string(expected), value[0])
-
-}

api/headers.go

@@ -1,5 +1,7 @@
 package api
 
+import "net/http"
+
 const (
 	VersionHeader                 = "Eth-Consensus-Version"
 	ExecutionPayloadBlindedHeader = "Eth-Execution-Payload-Blinded"
@@ -10,3 +12,9 @@ const (
 	EventStreamMediaType          = "text/event-stream"
 	KeepAlive                     = "keep-alive"
 )
+
+// SetSSEHeaders sets the headers needed for a server-sent event response.
+func SetSSEHeaders(w http.ResponseWriter) {
+	w.Header().Set("Content-Type", EventStreamMediaType)
+	w.Header().Set("Connection", KeepAlive)
+}

api/jwt.go

@@ -1,9 +1,9 @@
 package api
 
 import (
+	"github.com/OffchainLabs/prysm/v6/crypto/rand"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/crypto/rand"
 )
 
 // GenerateRandomHexString generates a random hex string that follows the standards for jwt token

api/jwt_test.go

@@ -3,7 +3,7 @@ package api
 import (
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 )
 
 func TestGenerateRandomHexString(t *testing.T) {

api/pagination/BUILD.bazel

@@ -3,7 +3,7 @@ load("@prysm//tools/go:def.bzl", "go_library", "go_test")
 go_library(
     name = "go_default_library",
     srcs = ["pagination.go"],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/pagination",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/pagination",
     visibility = ["//visibility:public"],
     deps = [
         "//config/params:go_default_library",

api/pagination/pagination.go

@@ -5,8 +5,8 @@ import (
 	"fmt"
 	"strconv"
 
+	"github.com/OffchainLabs/prysm/v6/config/params"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
 )
 
 // StartAndEndPage takes in the requested page token, wanted page size, total page size.

api/pagination/pagination_test.go

@@ -3,9 +3,9 @@ package pagination_test
 import (
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/api/pagination"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/api/pagination"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 )
 
 func TestStartAndEndPage(t *testing.T) {

api/server/BUILD.bazel

@@ -3,7 +3,7 @@ load("@prysm//tools/go:def.bzl", "go_library", "go_test")
 go_library(
     name = "go_default_library",
     srcs = ["error.go"],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/server",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/server",
     visibility = ["//visibility:public"],
 )
 

api/server/error_test.go

@@ -4,7 +4,7 @@ import (
 	"errors"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
 )
 
 func TestDecodeError(t *testing.T) {

api/server/httprest/BUILD.bazel

@@ -0,0 +1,31 @@
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "log.go",
+        "options.go",
+        "server.go",
+    ],
+    importpath = "github.com/OffchainLabs/prysm/v6/api/server/httprest",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//api/server/middleware:go_default_library",
+        "//runtime:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["server_test.go"],
+    embed = [":go_default_library"],
+    deps = [
+        "//cmd/beacon-chain/flags:go_default_library",
+        "//testing/assert:go_default_library",
+        "//testing/require:go_default_library",
+        "@com_github_sirupsen_logrus//hooks/test:go_default_library",
+        "@com_github_urfave_cli_v2//:go_default_library",
+    ],
+)

api/server/httprest/log.go

@@ -0,0 +1,5 @@
+package httprest
+
+import "github.com/sirupsen/logrus"
+
+var log = logrus.WithField("prefix", "httprest")

api/server/httprest/options.go

@@ -0,0 +1,44 @@
+package httprest
+
+import (
+	"time"
+
+	"net/http"
+
+	"github.com/OffchainLabs/prysm/v6/api/server/middleware"
+)
+
+// Option is a http rest server functional parameter type.
+type Option func(g *Server) error
+
+// WithMiddlewares sets the list of middlewares to be applied on routes.
+func WithMiddlewares(mw []middleware.Middleware) Option {
+	return func(g *Server) error {
+		g.cfg.middlewares = mw
+		return nil
+	}
+}
+
+// WithHTTPAddr sets the full address ( host and port ) of the server.
+func WithHTTPAddr(addr string) Option {
+	return func(g *Server) error {
+		g.cfg.httpAddr = addr
+		return nil
+	}
+}
+
+// WithRouter sets the internal router of the server, this is required.
+func WithRouter(r *http.ServeMux) Option {
+	return func(g *Server) error {
+		g.cfg.router = r
+		return nil
+	}
+}
+
+// WithTimeout allows changing the timeout value for API calls.
+func WithTimeout(duration time.Duration) Option {
+	return func(g *Server) error {
+		g.cfg.timeout = duration
+		return nil
+	}
+}

api/server/httprest/server.go

@@ -0,0 +1,101 @@
+package httprest
+
+import (
+	"context"
+	"net/http"
+	"time"
+
+	"github.com/OffchainLabs/prysm/v6/api/server/middleware"
+	"github.com/OffchainLabs/prysm/v6/runtime"
+	"github.com/pkg/errors"
+)
+
+var _ runtime.Service = (*Server)(nil)
+
+// Config parameters for setting up the http-rest service.
+type config struct {
+	httpAddr    string
+	middlewares []middleware.Middleware
+	router      http.Handler
+	timeout     time.Duration
+}
+
+// Server serves HTTP traffic.
+type Server struct {
+	cfg          *config
+	server       *http.Server
+	cancel       context.CancelFunc
+	ctx          context.Context
+	startFailure error
+}
+
+// New returns a new instance of the Server.
+func New(ctx context.Context, opts ...Option) (*Server, error) {
+	g := &Server{
+		ctx: ctx,
+		cfg: &config{},
+	}
+	for _, opt := range opts {
+		if err := opt(g); err != nil {
+			return nil, err
+		}
+	}
+	if g.cfg.router == nil {
+		return nil, errors.New("router option not configured")
+	}
+	var handler http.Handler
+	defaultReadHeaderTimeout := time.Second
+	handler = middleware.MiddlewareChain(g.cfg.router, g.cfg.middlewares)
+	if g.cfg.timeout > 0*time.Second {
+		defaultReadHeaderTimeout = g.cfg.timeout
+		handler = http.TimeoutHandler(handler, g.cfg.timeout, "request timed out")
+	}
+	g.server = &http.Server{
+		Addr:              g.cfg.httpAddr,
+		Handler:           handler,
+		ReadHeaderTimeout: defaultReadHeaderTimeout,
+	}
+
+	return g, nil
+}
+
+// Start the http rest service.
+func (g *Server) Start() {
+	g.ctx, g.cancel = context.WithCancel(g.ctx)
+
+	go func() {
+		log.WithField("address", g.cfg.httpAddr).Info("Starting HTTP server")
+		if err := g.server.ListenAndServe(); err != http.ErrServerClosed {
+			log.WithError(err).Error("Failed to start HTTP server")
+			g.startFailure = err
+			return
+		}
+	}()
+}
+
+// Status of the HTTP server. Returns an error if this service is unhealthy.
+func (g *Server) Status() error {
+	if g.startFailure != nil {
+		return g.startFailure
+	}
+	return nil
+}
+
+// Stop the HTTP server with a graceful shutdown.
+func (g *Server) Stop() error {
+	if g.server != nil {
+		shutdownCtx, shutdownCancel := context.WithTimeout(g.ctx, 2*time.Second)
+		defer shutdownCancel()
+		if err := g.server.Shutdown(shutdownCtx); err != nil {
+			if errors.Is(err, context.DeadlineExceeded) {
+				log.Warn("Existing connections terminated")
+			} else {
+				log.WithError(err).Error("Failed to gracefully shut down server")
+			}
+		}
+	}
+	if g.cancel != nil {
+		g.cancel()
+	}
+	return nil
+}

api/server/httprest/server_test.go

@@ -0,0 +1,70 @@
+package httprest
+
+import (
+	"flag"
+	"fmt"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+
+	"github.com/OffchainLabs/prysm/v6/cmd/beacon-chain/flags"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	logTest "github.com/sirupsen/logrus/hooks/test"
+	"github.com/urfave/cli/v2"
+)
+
+func TestServer_StartStop(t *testing.T) {
+	hook := logTest.NewGlobal()
+
+	app := cli.App{}
+	set := flag.NewFlagSet("test", 0)
+	ctx := cli.NewContext(&app, set, nil)
+
+	port := ctx.Int(flags.HTTPServerPort.Name)
+	portStr := fmt.Sprintf("%d", port) // Convert port to string
+	host := ctx.String(flags.HTTPServerHost.Name)
+	address := net.JoinHostPort(host, portStr)
+	handler := http.NewServeMux()
+	opts := []Option{
+		WithHTTPAddr(address),
+		WithRouter(handler),
+	}
+
+	g, err := New(t.Context(), opts...)
+	require.NoError(t, err)
+
+	g.Start()
+	go func() {
+		require.LogsContain(t, hook, "Starting HTTP server")
+		require.LogsDoNotContain(t, hook, "Starting API middleware")
+	}()
+	err = g.Stop()
+	require.NoError(t, err)
+}
+
+func TestServer_NilHandler_NotFoundHandlerRegistered(t *testing.T) {
+	app := cli.App{}
+	set := flag.NewFlagSet("test", 0)
+	ctx := cli.NewContext(&app, set, nil)
+
+	handler := http.NewServeMux()
+	port := ctx.Int(flags.HTTPServerPort.Name)
+	portStr := fmt.Sprintf("%d", port) // Convert port to string
+	host := ctx.String(flags.HTTPServerHost.Name)
+	address := net.JoinHostPort(host, portStr)
+
+	opts := []Option{
+		WithHTTPAddr(address),
+		WithRouter(handler),
+	}
+
+	g, err := New(t.Context(), opts...)
+	require.NoError(t, err)
+
+	writer := httptest.NewRecorder()
+	g.cfg.router.ServeHTTP(writer, &http.Request{Method: "GET", Host: "localhost", URL: &url.URL{Path: "/foo"}})
+	assert.Equal(t, http.StatusNotFound, writer.Code)
+}

api/server/middleware/BUILD.bazel

@@ -6,11 +6,13 @@ go_library(
         "middleware.go",
         "util.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/server/middleware",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/server/middleware",
     visibility = ["//visibility:public"],
     deps = [
-        "@com_github_gorilla_mux//:go_default_library",
+        "//api:go_default_library",
+        "//api/apiutil:go_default_library",
         "@com_github_rs_cors//:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
     ],
 )
 
@@ -25,5 +27,6 @@ go_test(
         "//api:go_default_library",
         "//testing/assert:go_default_library",
         "//testing/require:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
     ],
 )

api/server/middleware/middleware.go

@@ -1,14 +1,19 @@
 package middleware
 
 import (
+	"compress/gzip"
 	"fmt"
 	"net/http"
 	"strings"
 
-	"github.com/gorilla/mux"
+	"github.com/OffchainLabs/prysm/v6/api"
+	"github.com/OffchainLabs/prysm/v6/api/apiutil"
 	"github.com/rs/cors"
+	log "github.com/sirupsen/logrus"
 )
 
+type Middleware func(http.Handler) http.Handler
+
 // NormalizeQueryValuesHandler normalizes an input query of "key=value1,value2,value3" to "key=value1&key=value2&key=value3"
 func NormalizeQueryValuesHandler(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
@@ -21,7 +26,7 @@ func NormalizeQueryValuesHandler(next http.Handler) http.Handler {
 }
 
 // CorsHandler sets the cors settings on api endpoints
-func CorsHandler(allowOrigins []string) mux.MiddlewareFunc {
+func CorsHandler(allowOrigins []string) Middleware {
 	c := cors.New(cors.Options{
 		AllowedOrigins:   allowOrigins,
 		AllowedMethods:   []string{http.MethodPost, http.MethodGet, http.MethodDelete, http.MethodOptions},
@@ -34,7 +39,7 @@ func CorsHandler(allowOrigins []string) mux.MiddlewareFunc {
 }
 
 // ContentTypeHandler checks request for the appropriate media types otherwise returning a http.StatusUnsupportedMediaType error
-func ContentTypeHandler(acceptedMediaTypes []string) mux.MiddlewareFunc {
+func ContentTypeHandler(acceptedMediaTypes []string) Middleware {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			// skip the GET request
@@ -67,46 +72,75 @@ func ContentTypeHandler(acceptedMediaTypes []string) mux.MiddlewareFunc {
 }
 
 // AcceptHeaderHandler checks if the client's response preference is handled
-func AcceptHeaderHandler(serverAcceptedTypes []string) mux.MiddlewareFunc {
+func AcceptHeaderHandler(serverAcceptedTypes []string) Middleware {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			acceptHeader := r.Header.Get("Accept")
-			// header is optional and should skip if not provided
-			if acceptHeader == "" {
-				next.ServeHTTP(w, r)
+			if _, ok := apiutil.Negotiate(r.Header.Get("Accept"), serverAcceptedTypes); !ok {
+				http.Error(w, "Not Acceptable", http.StatusNotAcceptable)
 				return
 			}
-
-			accepted := false
-			acceptTypes := strings.Split(acceptHeader, ",")
-			// follows rules defined in https://datatracker.ietf.org/doc/html/rfc2616#section-14.1
-			for _, acceptType := range acceptTypes {
-				acceptType = strings.TrimSpace(acceptType)
-				if acceptType == "*/*" {
-					accepted = true
-					break
-				}
-				for _, serverAcceptedType := range serverAcceptedTypes {
-					if strings.HasPrefix(acceptType, serverAcceptedType) {
-						accepted = true
-						break
-					}
-					if acceptType != "/*" && strings.HasSuffix(acceptType, "/*") && strings.HasPrefix(serverAcceptedType, acceptType[:len(acceptType)-2]) {
-						accepted = true
-						break
-					}
-				}
-				if accepted {
-					break
-				}
-			}
-
-			if !accepted {
-				http.Error(w, fmt.Sprintf("Not Acceptable: %s", acceptHeader), http.StatusNotAcceptable)
-				return
-			}
-
 			next.ServeHTTP(w, r)
 		})
 	}
 }
+
+// AcceptEncodingHeaderHandler compresses the response before sending it back to the client, if gzip is supported.
+func AcceptEncodingHeaderHandler() Middleware {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
+				next.ServeHTTP(w, r)
+				return
+			}
+
+			gz := gzip.NewWriter(w)
+			gzipRW := &gzipResponseWriter{gz: gz, ResponseWriter: w}
+			defer func() {
+				if !gzipRW.zip {
+					return
+				}
+				if err := gz.Close(); err != nil {
+					log.WithError(err).Error("Failed to close gzip writer")
+				}
+			}()
+
+			next.ServeHTTP(gzipRW, r)
+		})
+	}
+}
+
+type gzipResponseWriter struct {
+	gz *gzip.Writer
+	http.ResponseWriter
+	zip bool
+}
+
+func (g *gzipResponseWriter) WriteHeader(statusCode int) {
+	if strings.Contains(g.Header().Get("Content-Type"), api.JsonMediaType) {
+		// Removing the current Content-Length because zipping will change it.
+		g.Header().Del("Content-Length")
+		g.Header().Set("Content-Encoding", "gzip")
+		g.zip = true
+	}
+
+	g.ResponseWriter.WriteHeader(statusCode)
+}
+
+func (g *gzipResponseWriter) Write(b []byte) (int, error) {
+	if g.zip {
+		return g.gz.Write(b)
+	}
+	return g.ResponseWriter.Write(b)
+}
+
+func MiddlewareChain(h http.Handler, mw []Middleware) http.Handler {
+	if len(mw) < 1 {
+		return h
+	}
+
+	wrapped := h
+	for i := len(mw) - 1; i >= 0; i-- {
+		wrapped = mw[i](wrapped)
+	}
+	return wrapped
+}

api/server/middleware/middleware_test.go

@@ -1,14 +1,35 @@
 package middleware
 
 import (
+	"bytes"
+	"compress/gzip"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/api"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/api"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	log "github.com/sirupsen/logrus"
 )
 
+// frozenHeaderRecorder allows asserting that response headers were not modified
+// after the call to WriteHeader.
+//
+// Its purpose is to have a regression test for https://github.com/OffchainLabs/prysm/pull/15499.
+type frozenHeaderRecorder struct {
+	*httptest.ResponseRecorder
+	frozenHeader http.Header
+}
+
+func (r *frozenHeaderRecorder) WriteHeader(code int) {
+	if r.frozenHeader != nil {
+		return
+	}
+	r.ResponseRecorder.WriteHeader(code)
+	r.frozenHeader = r.ResponseRecorder.Header().Clone()
+}
+
 func TestNormalizeQueryValuesHandler(t *testing.T) {
 	nextHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		_, err := w.Write([]byte("next handler"))
@@ -124,6 +145,90 @@ func TestContentTypeHandler(t *testing.T) {
 	}
 }
 
+func TestAcceptEncodingHeaderHandler(t *testing.T) {
+	dummyContent := "Test gzip middleware content"
+	nextHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", r.Header.Get("Accept"))
+		w.WriteHeader(http.StatusOK)
+		_, err := w.Write([]byte(dummyContent))
+		require.NoError(t, err)
+	})
+
+	handler := AcceptEncodingHeaderHandler()(nextHandler)
+
+	tests := []struct {
+		name             string
+		accept           string
+		acceptEncoding   string
+		expectCompressed bool
+	}{
+		{
+			name:             "Accept gzip",
+			accept:           api.JsonMediaType,
+			acceptEncoding:   "gzip",
+			expectCompressed: true,
+		},
+		{
+			name:             "Accept multiple encodings",
+			accept:           api.JsonMediaType,
+			acceptEncoding:   "deflate, gzip",
+			expectCompressed: true,
+		},
+		{
+			name:             "Accept unsupported encoding",
+			accept:           api.JsonMediaType,
+			acceptEncoding:   "deflate",
+			expectCompressed: false,
+		},
+		{
+			name:             "No accept encoding header",
+			accept:           api.JsonMediaType,
+			acceptEncoding:   "",
+			expectCompressed: false,
+		},
+		{
+			name:             "SSZ",
+			accept:           api.OctetStreamMediaType,
+			acceptEncoding:   "gzip",
+			expectCompressed: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := httptest.NewRequest("GET", "/", nil)
+			req.Header.Set("Accept", tt.accept)
+			if tt.acceptEncoding != "" {
+				req.Header.Set("Accept-Encoding", tt.acceptEncoding)
+			}
+			rr := &frozenHeaderRecorder{ResponseRecorder: httptest.NewRecorder()}
+
+			handler.ServeHTTP(rr, req)
+
+			if tt.expectCompressed {
+				require.Equal(t, "gzip", rr.frozenHeader.Get("Content-Encoding"), "Expected Content-Encoding header to be 'gzip'")
+
+				compressedBody := rr.Body.Bytes()
+				require.NotEqual(t, dummyContent, string(compressedBody), "Response body should be compressed and differ from the original")
+
+				gzReader, err := gzip.NewReader(bytes.NewReader(compressedBody))
+				require.NoError(t, err, "Failed to create gzipReader")
+				defer func() {
+					if err := gzReader.Close(); err != nil {
+						log.WithError(err).Error("Failed to close gzip reader")
+					}
+				}()
+
+				decompressedBody, err := io.ReadAll(gzReader)
+				require.NoError(t, err, "Failed to decompress response body")
+				require.Equal(t, dummyContent, string(decompressedBody), "Decompressed content should match the original")
+			} else {
+				require.Equal(t, dummyContent, rr.Body.String(), "Response body should be uncompressed and match the original")
+			}
+		})
+	}
+}
+
 func TestAcceptHeaderHandler(t *testing.T) {
 	acceptedTypes := []string{"application/json", "application/octet-stream"}
 

api/server/middleware/util_test.go

@@ -3,8 +3,8 @@ package middleware
 import (
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 )
 
 func TestNormalizeQueryValues(t *testing.T) {

api/server/structs/BUILD.bazel

@@ -4,8 +4,12 @@ go_library(
     name = "go_default_library",
     srcs = [
         "block.go",
+        "block_execution.go",
         "conversions.go",
+        "conversions_blob.go",
         "conversions_block.go",
+        "conversions_block_execution.go",
+        "conversions_lightclient.go",
         "conversions_state.go",
         "endpoints_beacon.go",
         "endpoints_blob.go",
@@ -20,32 +24,45 @@ go_library(
         "other.go",
         "state.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/server/structs",
+    importpath = "github.com/OffchainLabs/prysm/v6/api/server/structs",
     visibility = ["//visibility:public"],
     deps = [
         "//api/server:go_default_library",
         "//beacon-chain/state:go_default_library",
         "//config/fieldparams:go_default_library",
+        "//config/params:go_default_library",
+        "//consensus-types/blocks:go_default_library",
         "//consensus-types/interfaces:go_default_library",
         "//consensus-types/primitives:go_default_library",
         "//consensus-types/validator:go_default_library",
         "//container/slice:go_default_library",
+        "//crypto/bls:go_default_library",
         "//encoding/bytesutil:go_default_library",
         "//math:go_default_library",
         "//proto/engine/v1:go_default_library",
+        "//proto/eth/v1:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
+        "//runtime/version:go_default_library",
         "@com_github_ethereum_go_ethereum//common:go_default_library",
         "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
+        "@org_golang_google_protobuf//proto:go_default_library",
     ],
 )
 
 go_test(
     name = "go_default_test",
-    srcs = ["conversions_test.go"],
+    srcs = [
+        "conversions_block_execution_test.go",
+        "conversions_test.go",
+    ],
     embed = [":go_default_library"],
     deps = [
+        "//proto/engine/v1:go_default_library",
         "//proto/prysm/v1alpha1:go_default_library",
+        "//testing/assert:go_default_library",
         "//testing/require:go_default_library",
+        "@com_github_ethereum_go_ethereum//common:go_default_library",
+        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
     ],
 )

api/server/structs/block.go

@@ -14,6 +14,10 @@ type SignedMessageJsoner interface {
 	SigString() string
 }
 
+// ----------------------------------------------------------------------------
+// Phase 0
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlock struct {
 	Message   *BeaconBlock `json:"message"`
 	Signature string       `json:"signature"`
@@ -48,6 +52,29 @@ type BeaconBlockBody struct {
 	VoluntaryExits    []*SignedVoluntaryExit `json:"voluntary_exits"`
 }
 
+type SignedBeaconBlockHeaderContainer struct {
+	Header    *SignedBeaconBlockHeader `json:"header"`
+	Root      string                   `json:"root"`
+	Canonical bool                     `json:"canonical"`
+}
+
+type SignedBeaconBlockHeader struct {
+	Message   *BeaconBlockHeader `json:"message"`
+	Signature string             `json:"signature"`
+}
+
+type BeaconBlockHeader struct {
+	Slot          string `json:"slot"`
+	ProposerIndex string `json:"proposer_index"`
+	ParentRoot    string `json:"parent_root"`
+	StateRoot     string `json:"state_root"`
+	BodyRoot      string `json:"body_root"`
+}
+
+// ----------------------------------------------------------------------------
+// Altair
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockAltair struct {
 	Message   *BeaconBlockAltair `json:"message"`
 	Signature string             `json:"signature"`
@@ -83,6 +110,10 @@ type BeaconBlockBodyAltair struct {
 	SyncAggregate     *SyncAggregate         `json:"sync_aggregate"`
 }
 
+// ----------------------------------------------------------------------------
+// Bellatrix
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockBellatrix struct {
 	Message   *BeaconBlockBellatrix `json:"message"`
 	Signature string                `json:"signature"`
@@ -155,6 +186,10 @@ type BlindedBeaconBlockBodyBellatrix struct {
 	ExecutionPayloadHeader *ExecutionPayloadHeader `json:"execution_payload_header"`
 }
 
+// ----------------------------------------------------------------------------
+// Capella
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockCapella struct {
 	Message   *BeaconBlockCapella `json:"message"`
 	Signature string              `json:"signature"`
@@ -229,6 +264,10 @@ type BlindedBeaconBlockBodyCapella struct {
 	BLSToExecutionChanges  []*SignedBLSToExecutionChange  `json:"bls_to_execution_changes"`
 }
 
+// ----------------------------------------------------------------------------
+// Deneb
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockContentsDeneb struct {
 	SignedBlock *SignedBeaconBlockDeneb `json:"signed_block"`
 	KzgProofs   []string                `json:"kzg_proofs"`
@@ -317,6 +356,10 @@ type BlindedBeaconBlockBodyDeneb struct {
 	BlobKzgCommitments     []string                      `json:"blob_kzg_commitments"`
 }
 
+// ----------------------------------------------------------------------------
+// Electra
+// ----------------------------------------------------------------------------
+
 type SignedBeaconBlockContentsElectra struct {
 	SignedBlock *SignedBeaconBlockElectra `json:"signed_block"`
 	KzgProofs   []string                  `json:"kzg_proofs"`
@@ -362,9 +405,10 @@ type BeaconBlockBodyElectra struct {
 	Deposits              []*Deposit                    `json:"deposits"`
 	VoluntaryExits        []*SignedVoluntaryExit        `json:"voluntary_exits"`
 	SyncAggregate         *SyncAggregate                `json:"sync_aggregate"`
-	ExecutionPayload      *ExecutionPayloadElectra      `json:"execution_payload"`
+	ExecutionPayload      *ExecutionPayloadDeneb        `json:"execution_payload"`
 	BLSToExecutionChanges []*SignedBLSToExecutionChange `json:"bls_to_execution_changes"`
 	BlobKzgCommitments    []string                      `json:"blob_kzg_commitments"`
+	ExecutionRequests     *ExecutionRequests            `json:"execution_requests"`
 }
 
 type BlindedBeaconBlockElectra struct {
@@ -391,191 +435,71 @@ func (s *SignedBlindedBeaconBlockElectra) SigString() string {
 }
 
 type BlindedBeaconBlockBodyElectra struct {
-	RandaoReveal           string                         `json:"randao_reveal"`
-	Eth1Data               *Eth1Data                      `json:"eth1_data"`
-	Graffiti               string                         `json:"graffiti"`
-	ProposerSlashings      []*ProposerSlashing            `json:"proposer_slashings"`
-	AttesterSlashings      []*AttesterSlashingElectra     `json:"attester_slashings"`
-	Attestations           []*AttestationElectra          `json:"attestations"`
-	Deposits               []*Deposit                     `json:"deposits"`
-	VoluntaryExits         []*SignedVoluntaryExit         `json:"voluntary_exits"`
-	SyncAggregate          *SyncAggregate                 `json:"sync_aggregate"`
-	ExecutionPayloadHeader *ExecutionPayloadHeaderElectra `json:"execution_payload_header"`
-	BLSToExecutionChanges  []*SignedBLSToExecutionChange  `json:"bls_to_execution_changes"`
-	BlobKzgCommitments     []string                       `json:"blob_kzg_commitments"`
+	RandaoReveal           string                        `json:"randao_reveal"`
+	Eth1Data               *Eth1Data                     `json:"eth1_data"`
+	Graffiti               string                        `json:"graffiti"`
+	ProposerSlashings      []*ProposerSlashing           `json:"proposer_slashings"`
+	AttesterSlashings      []*AttesterSlashingElectra    `json:"attester_slashings"`
+	Attestations           []*AttestationElectra         `json:"attestations"`
+	Deposits               []*Deposit                    `json:"deposits"`
+	VoluntaryExits         []*SignedVoluntaryExit        `json:"voluntary_exits"`
+	SyncAggregate          *SyncAggregate                `json:"sync_aggregate"`
+	ExecutionPayloadHeader *ExecutionPayloadHeaderDeneb  `json:"execution_payload_header"`
+	BLSToExecutionChanges  []*SignedBLSToExecutionChange `json:"bls_to_execution_changes"`
+	BlobKzgCommitments     []string                      `json:"blob_kzg_commitments"`
+	ExecutionRequests      *ExecutionRequests            `json:"execution_requests"`
 }
 
-type SignedBeaconBlockHeaderContainer struct {
-	Header    *SignedBeaconBlockHeader `json:"header"`
-	Root      string                   `json:"root"`
-	Canonical bool                     `json:"canonical"`
+// ----------------------------------------------------------------------------
+// Fulu
+// ----------------------------------------------------------------------------
+
+type SignedBeaconBlockContentsFulu struct {
+	SignedBlock *SignedBeaconBlockFulu `json:"signed_block"`
+	KzgProofs   []string               `json:"kzg_proofs"`
+	Blobs       []string               `json:"blobs"`
 }
 
-type SignedBeaconBlockHeader struct {
-	Message   *BeaconBlockHeader `json:"message"`
-	Signature string             `json:"signature"`
+type BeaconBlockContentsFulu struct {
+	Block     *BeaconBlockElectra `json:"block"`
+	KzgProofs []string            `json:"kzg_proofs"`
+	Blobs     []string            `json:"blobs"`
 }
 
-type BeaconBlockHeader struct {
-	Slot          string `json:"slot"`
-	ProposerIndex string `json:"proposer_index"`
-	ParentRoot    string `json:"parent_root"`
-	StateRoot     string `json:"state_root"`
-	BodyRoot      string `json:"body_root"`
+type SignedBeaconBlockFulu struct {
+	Message   *BeaconBlockElectra `json:"message"`
+	Signature string              `json:"signature"`
 }
 
-type ExecutionPayload struct {
-	ParentHash    string   `json:"parent_hash"`
-	FeeRecipient  string   `json:"fee_recipient"`
-	StateRoot     string   `json:"state_root"`
-	ReceiptsRoot  string   `json:"receipts_root"`
-	LogsBloom     string   `json:"logs_bloom"`
-	PrevRandao    string   `json:"prev_randao"`
-	BlockNumber   string   `json:"block_number"`
-	GasLimit      string   `json:"gas_limit"`
-	GasUsed       string   `json:"gas_used"`
-	Timestamp     string   `json:"timestamp"`
-	ExtraData     string   `json:"extra_data"`
-	BaseFeePerGas string   `json:"base_fee_per_gas"`
-	BlockHash     string   `json:"block_hash"`
-	Transactions  []string `json:"transactions"`
+var _ SignedMessageJsoner = &SignedBeaconBlockFulu{}
+
+func (s *SignedBeaconBlockFulu) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
 }
 
-type ExecutionPayloadHeader struct {
-	ParentHash       string `json:"parent_hash"`
-	FeeRecipient     string `json:"fee_recipient"`
-	StateRoot        string `json:"state_root"`
-	ReceiptsRoot     string `json:"receipts_root"`
-	LogsBloom        string `json:"logs_bloom"`
-	PrevRandao       string `json:"prev_randao"`
-	BlockNumber      string `json:"block_number"`
-	GasLimit         string `json:"gas_limit"`
-	GasUsed          string `json:"gas_used"`
-	Timestamp        string `json:"timestamp"`
-	ExtraData        string `json:"extra_data"`
-	BaseFeePerGas    string `json:"base_fee_per_gas"`
-	BlockHash        string `json:"block_hash"`
-	TransactionsRoot string `json:"transactions_root"`
+func (s *SignedBeaconBlockFulu) SigString() string {
+	return s.Signature
 }
 
-type ExecutionPayloadCapella struct {
-	ParentHash    string        `json:"parent_hash"`
-	FeeRecipient  string        `json:"fee_recipient"`
-	StateRoot     string        `json:"state_root"`
-	ReceiptsRoot  string        `json:"receipts_root"`
-	LogsBloom     string        `json:"logs_bloom"`
-	PrevRandao    string        `json:"prev_randao"`
-	BlockNumber   string        `json:"block_number"`
-	GasLimit      string        `json:"gas_limit"`
-	GasUsed       string        `json:"gas_used"`
-	Timestamp     string        `json:"timestamp"`
-	ExtraData     string        `json:"extra_data"`
-	BaseFeePerGas string        `json:"base_fee_per_gas"`
-	BlockHash     string        `json:"block_hash"`
-	Transactions  []string      `json:"transactions"`
-	Withdrawals   []*Withdrawal `json:"withdrawals"`
+type BlindedBeaconBlockFulu struct {
+	Slot          string                         `json:"slot"`
+	ProposerIndex string                         `json:"proposer_index"`
+	ParentRoot    string                         `json:"parent_root"`
+	StateRoot     string                         `json:"state_root"`
+	Body          *BlindedBeaconBlockBodyElectra `json:"body"`
 }
 
-type ExecutionPayloadHeaderCapella struct {
-	ParentHash       string `json:"parent_hash"`
-	FeeRecipient     string `json:"fee_recipient"`
-	StateRoot        string `json:"state_root"`
-	ReceiptsRoot     string `json:"receipts_root"`
-	LogsBloom        string `json:"logs_bloom"`
-	PrevRandao       string `json:"prev_randao"`
-	BlockNumber      string `json:"block_number"`
-	GasLimit         string `json:"gas_limit"`
-	GasUsed          string `json:"gas_used"`
-	Timestamp        string `json:"timestamp"`
-	ExtraData        string `json:"extra_data"`
-	BaseFeePerGas    string `json:"base_fee_per_gas"`
-	BlockHash        string `json:"block_hash"`
-	TransactionsRoot string `json:"transactions_root"`
-	WithdrawalsRoot  string `json:"withdrawals_root"`
+type SignedBlindedBeaconBlockFulu struct {
+	Message   *BlindedBeaconBlockFulu `json:"message"`
+	Signature string                  `json:"signature"`
 }
 
-type ExecutionPayloadDeneb struct {
-	ParentHash    string        `json:"parent_hash"`
-	FeeRecipient  string        `json:"fee_recipient"`
-	StateRoot     string        `json:"state_root"`
-	ReceiptsRoot  string        `json:"receipts_root"`
-	LogsBloom     string        `json:"logs_bloom"`
-	PrevRandao    string        `json:"prev_randao"`
-	BlockNumber   string        `json:"block_number"`
-	GasLimit      string        `json:"gas_limit"`
-	GasUsed       string        `json:"gas_used"`
-	Timestamp     string        `json:"timestamp"`
-	ExtraData     string        `json:"extra_data"`
-	BaseFeePerGas string        `json:"base_fee_per_gas"`
-	BlockHash     string        `json:"block_hash"`
-	Transactions  []string      `json:"transactions"`
-	Withdrawals   []*Withdrawal `json:"withdrawals"`
-	BlobGasUsed   string        `json:"blob_gas_used"`
-	ExcessBlobGas string        `json:"excess_blob_gas"`
+var _ SignedMessageJsoner = &SignedBlindedBeaconBlockFulu{}
+
+func (s *SignedBlindedBeaconBlockFulu) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
 }
 
-type ExecutionPayloadHeaderDeneb struct {
-	ParentHash       string `json:"parent_hash"`
-	FeeRecipient     string `json:"fee_recipient"`
-	StateRoot        string `json:"state_root"`
-	ReceiptsRoot     string `json:"receipts_root"`
-	LogsBloom        string `json:"logs_bloom"`
-	PrevRandao       string `json:"prev_randao"`
-	BlockNumber      string `json:"block_number"`
-	GasLimit         string `json:"gas_limit"`
-	GasUsed          string `json:"gas_used"`
-	Timestamp        string `json:"timestamp"`
-	ExtraData        string `json:"extra_data"`
-	BaseFeePerGas    string `json:"base_fee_per_gas"`
-	BlockHash        string `json:"block_hash"`
-	TransactionsRoot string `json:"transactions_root"`
-	WithdrawalsRoot  string `json:"withdrawals_root"`
-	BlobGasUsed      string `json:"blob_gas_used"`
-	ExcessBlobGas    string `json:"excess_blob_gas"`
-}
-
-type ExecutionPayloadElectra struct {
-	ParentHash            string                  `json:"parent_hash"`
-	FeeRecipient          string                  `json:"fee_recipient"`
-	StateRoot             string                  `json:"state_root"`
-	ReceiptsRoot          string                  `json:"receipts_root"`
-	LogsBloom             string                  `json:"logs_bloom"`
-	PrevRandao            string                  `json:"prev_randao"`
-	BlockNumber           string                  `json:"block_number"`
-	GasLimit              string                  `json:"gas_limit"`
-	GasUsed               string                  `json:"gas_used"`
-	Timestamp             string                  `json:"timestamp"`
-	ExtraData             string                  `json:"extra_data"`
-	BaseFeePerGas         string                  `json:"base_fee_per_gas"`
-	BlockHash             string                  `json:"block_hash"`
-	Transactions          []string                `json:"transactions"`
-	Withdrawals           []*Withdrawal           `json:"withdrawals"`
-	BlobGasUsed           string                  `json:"blob_gas_used"`
-	ExcessBlobGas         string                  `json:"excess_blob_gas"`
-	DepositRequests       []*DepositRequest       `json:"deposit_requests"`
-	WithdrawalRequests    []*WithdrawalRequest    `json:"withdrawal_requests"`
-	ConsolidationRequests []*ConsolidationRequest `json:"consolidation_requests"`
-}
-
-type ExecutionPayloadHeaderElectra struct {
-	ParentHash                string `json:"parent_hash"`
-	FeeRecipient              string `json:"fee_recipient"`
-	StateRoot                 string `json:"state_root"`
-	ReceiptsRoot              string `json:"receipts_root"`
-	LogsBloom                 string `json:"logs_bloom"`
-	PrevRandao                string `json:"prev_randao"`
-	BlockNumber               string `json:"block_number"`
-	GasLimit                  string `json:"gas_limit"`
-	GasUsed                   string `json:"gas_used"`
-	Timestamp                 string `json:"timestamp"`
-	ExtraData                 string `json:"extra_data"`
-	BaseFeePerGas             string `json:"base_fee_per_gas"`
-	BlockHash                 string `json:"block_hash"`
-	TransactionsRoot          string `json:"transactions_root"`
-	WithdrawalsRoot           string `json:"withdrawals_root"`
-	BlobGasUsed               string `json:"blob_gas_used"`
-	ExcessBlobGas             string `json:"excess_blob_gas"`
-	DepositRequestsRoot       string `json:"deposit_requests_root"`
-	WithdrawalRequestsRoot    string `json:"withdrawal_requests_root"`
-	ConsolidationRequestsRoot string `json:"consolidation_requests_root"`
+func (s *SignedBlindedBeaconBlockFulu) SigString() string {
+	return s.Signature
 }

api/server/structs/block_execution.go

@@ -0,0 +1,157 @@
+package structs
+
+// ----------------------------------------------------------------------------
+// Bellatrix
+// ----------------------------------------------------------------------------
+
+type ExecutionPayload struct {
+	ParentHash    string   `json:"parent_hash"`
+	FeeRecipient  string   `json:"fee_recipient"`
+	StateRoot     string   `json:"state_root"`
+	ReceiptsRoot  string   `json:"receipts_root"`
+	LogsBloom     string   `json:"logs_bloom"`
+	PrevRandao    string   `json:"prev_randao"`
+	BlockNumber   string   `json:"block_number"`
+	GasLimit      string   `json:"gas_limit"`
+	GasUsed       string   `json:"gas_used"`
+	Timestamp     string   `json:"timestamp"`
+	ExtraData     string   `json:"extra_data"`
+	BaseFeePerGas string   `json:"base_fee_per_gas"`
+	BlockHash     string   `json:"block_hash"`
+	Transactions  []string `json:"transactions"`
+}
+
+type ExecutionPayloadHeader struct {
+	ParentHash       string `json:"parent_hash"`
+	FeeRecipient     string `json:"fee_recipient"`
+	StateRoot        string `json:"state_root"`
+	ReceiptsRoot     string `json:"receipts_root"`
+	LogsBloom        string `json:"logs_bloom"`
+	PrevRandao       string `json:"prev_randao"`
+	BlockNumber      string `json:"block_number"`
+	GasLimit         string `json:"gas_limit"`
+	GasUsed          string `json:"gas_used"`
+	Timestamp        string `json:"timestamp"`
+	ExtraData        string `json:"extra_data"`
+	BaseFeePerGas    string `json:"base_fee_per_gas"`
+	BlockHash        string `json:"block_hash"`
+	TransactionsRoot string `json:"transactions_root"`
+}
+
+// ----------------------------------------------------------------------------
+// Capella
+// ----------------------------------------------------------------------------
+
+type ExecutionPayloadCapella struct {
+	ParentHash    string        `json:"parent_hash"`
+	FeeRecipient  string        `json:"fee_recipient"`
+	StateRoot     string        `json:"state_root"`
+	ReceiptsRoot  string        `json:"receipts_root"`
+	LogsBloom     string        `json:"logs_bloom"`
+	PrevRandao    string        `json:"prev_randao"`
+	BlockNumber   string        `json:"block_number"`
+	GasLimit      string        `json:"gas_limit"`
+	GasUsed       string        `json:"gas_used"`
+	Timestamp     string        `json:"timestamp"`
+	ExtraData     string        `json:"extra_data"`
+	BaseFeePerGas string        `json:"base_fee_per_gas"`
+	BlockHash     string        `json:"block_hash"`
+	Transactions  []string      `json:"transactions"`
+	Withdrawals   []*Withdrawal `json:"withdrawals"`
+}
+
+type ExecutionPayloadHeaderCapella struct {
+	ParentHash       string `json:"parent_hash"`
+	FeeRecipient     string `json:"fee_recipient"`
+	StateRoot        string `json:"state_root"`
+	ReceiptsRoot     string `json:"receipts_root"`
+	LogsBloom        string `json:"logs_bloom"`
+	PrevRandao       string `json:"prev_randao"`
+	BlockNumber      string `json:"block_number"`
+	GasLimit         string `json:"gas_limit"`
+	GasUsed          string `json:"gas_used"`
+	Timestamp        string `json:"timestamp"`
+	ExtraData        string `json:"extra_data"`
+	BaseFeePerGas    string `json:"base_fee_per_gas"`
+	BlockHash        string `json:"block_hash"`
+	TransactionsRoot string `json:"transactions_root"`
+	WithdrawalsRoot  string `json:"withdrawals_root"`
+}
+
+// ----------------------------------------------------------------------------
+// Deneb
+// ----------------------------------------------------------------------------
+
+type ExecutionPayloadDeneb struct {
+	ParentHash    string        `json:"parent_hash"`
+	FeeRecipient  string        `json:"fee_recipient"`
+	StateRoot     string        `json:"state_root"`
+	ReceiptsRoot  string        `json:"receipts_root"`
+	LogsBloom     string        `json:"logs_bloom"`
+	PrevRandao    string        `json:"prev_randao"`
+	BlockNumber   string        `json:"block_number"`
+	GasLimit      string        `json:"gas_limit"`
+	GasUsed       string        `json:"gas_used"`
+	Timestamp     string        `json:"timestamp"`
+	ExtraData     string        `json:"extra_data"`
+	BaseFeePerGas string        `json:"base_fee_per_gas"`
+	BlockHash     string        `json:"block_hash"`
+	Transactions  []string      `json:"transactions"`
+	Withdrawals   []*Withdrawal `json:"withdrawals"`
+	BlobGasUsed   string        `json:"blob_gas_used"`
+	ExcessBlobGas string        `json:"excess_blob_gas"`
+}
+
+type ExecutionPayloadHeaderDeneb struct {
+	ParentHash       string `json:"parent_hash"`
+	FeeRecipient     string `json:"fee_recipient"`
+	StateRoot        string `json:"state_root"`
+	ReceiptsRoot     string `json:"receipts_root"`
+	LogsBloom        string `json:"logs_bloom"`
+	PrevRandao       string `json:"prev_randao"`
+	BlockNumber      string `json:"block_number"`
+	GasLimit         string `json:"gas_limit"`
+	GasUsed          string `json:"gas_used"`
+	Timestamp        string `json:"timestamp"`
+	ExtraData        string `json:"extra_data"`
+	BaseFeePerGas    string `json:"base_fee_per_gas"`
+	BlockHash        string `json:"block_hash"`
+	TransactionsRoot string `json:"transactions_root"`
+	WithdrawalsRoot  string `json:"withdrawals_root"`
+	BlobGasUsed      string `json:"blob_gas_used"`
+	ExcessBlobGas    string `json:"excess_blob_gas"`
+}
+
+// ----------------------------------------------------------------------------
+// Electra
+// ----------------------------------------------------------------------------
+
+type ExecutionRequests struct {
+	Deposits       []*DepositRequest       `json:"deposits"`
+	Withdrawals    []*WithdrawalRequest    `json:"withdrawals"`
+	Consolidations []*ConsolidationRequest `json:"consolidations"`
+}
+
+type DepositRequest struct {
+	Pubkey                string `json:"pubkey"`
+	WithdrawalCredentials string `json:"withdrawal_credentials"`
+	Amount                string `json:"amount"`
+	Signature             string `json:"signature"`
+	Index                 string `json:"index"`
+}
+
+type WithdrawalRequest struct {
+	SourceAddress   string `json:"source_address"`
+	ValidatorPubkey string `json:"validator_pubkey"`
+	Amount          string `json:"amount"`
+}
+
+type ConsolidationRequest struct {
+	SourceAddress string `json:"source_address"`
+	SourcePubkey  string `json:"source_pubkey"`
+	TargetPubkey  string `json:"target_pubkey"`
+}
+
+// ----------------------------------------------------------------------------
+// Fulu
+// ----------------------------------------------------------------------------

api/server/structs/conversions.go

@@ -4,18 +4,21 @@ import (
 	"fmt"
 	"strconv"
 
+	"github.com/OffchainLabs/prysm/v6/api/server"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/validator"
+	"github.com/OffchainLabs/prysm/v6/container/slice"
+	"github.com/OffchainLabs/prysm/v6/crypto/bls"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	"github.com/OffchainLabs/prysm/v6/math"
+	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	ethv1 "github.com/OffchainLabs/prysm/v6/proto/eth/v1"
+	eth "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/api/server"
-	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/validator"
-	"github.com/prysmaticlabs/prysm/v5/container/slice"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	"github.com/prysmaticlabs/prysm/v5/math"
-	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 )
 
 var errNilValue = errors.New("nil value")
@@ -50,6 +53,9 @@ func HistoricalSummaryFromConsensus(s *eth.HistoricalSummary) *HistoricalSummary
 }
 
 func (s *SignedBLSToExecutionChange) ToConsensus() (*eth.SignedBLSToExecutionChange, error) {
+	if s.Message == nil {
+		return nil, server.NewDecodeError(errNilValue, "Message")
+	}
 	change, err := s.Message.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Message")
@@ -101,14 +107,17 @@ func SignedBLSChangeFromConsensus(ch *eth.SignedBLSToExecutionChange) *SignedBLS
 
 func SignedBLSChangesToConsensus(src []*SignedBLSToExecutionChange) ([]*eth.SignedBLSToExecutionChange, error) {
 	if src == nil {
-		return nil, errNilValue
+		return nil, server.NewDecodeError(errNilValue, "SignedBLSToExecutionChanges")
 	}
 	err := slice.VerifyMaxLength(src, 16)
 	if err != nil {
-		return nil, err
+		return nil, server.NewDecodeError(err, "SignedBLSToExecutionChanges")
 	}
 	changes := make([]*eth.SignedBLSToExecutionChange, len(src))
 	for i, ch := range src {
+		if ch == nil {
+			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d]", i))
+		}
 		changes[i], err = ch.ToConsensus()
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d]", i))
@@ -154,6 +163,9 @@ func ForkFromConsensus(f *eth.Fork) *Fork {
 }
 
 func (s *SignedValidatorRegistration) ToConsensus() (*eth.SignedValidatorRegistrationV1, error) {
+	if s.Message == nil {
+		return nil, server.NewDecodeError(errNilValue, "Message")
+	}
 	msg, err := s.Message.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Message")
@@ -210,6 +222,9 @@ func SignedValidatorRegistrationFromConsensus(vr *eth.SignedValidatorRegistratio
 }
 
 func (s *SignedContributionAndProof) ToConsensus() (*eth.SignedContributionAndProof, error) {
+	if s.Message == nil {
+		return nil, server.NewDecodeError(errNilValue, "Message")
+	}
 	msg, err := s.Message.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Message")
@@ -234,6 +249,9 @@ func SignedContributionAndProofFromConsensus(c *eth.SignedContributionAndProof)
 }
 
 func (c *ContributionAndProof) ToConsensus() (*eth.ContributionAndProof, error) {
+	if c.Contribution == nil {
+		return nil, server.NewDecodeError(errNilValue, "Contribution")
+	}
 	contribution, err := c.Contribution.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Contribution")
@@ -242,7 +260,7 @@ func (c *ContributionAndProof) ToConsensus() (*eth.ContributionAndProof, error)
 	if err != nil {
 		return nil, server.NewDecodeError(err, "AggregatorIndex")
 	}
-	selectionProof, err := bytesutil.DecodeHexWithLength(c.SelectionProof, 96)
+	selectionProof, err := bytesutil.DecodeHexWithLength(c.SelectionProof, fieldparams.BLSSignatureLength)
 	if err != nil {
 		return nil, server.NewDecodeError(err, "SelectionProof")
 	}
@@ -305,6 +323,9 @@ func SyncCommitteeContributionFromConsensus(c *eth.SyncCommitteeContribution) *S
 }
 
 func (s *SignedAggregateAttestationAndProof) ToConsensus() (*eth.SignedAggregateAttestationAndProof, error) {
+	if s.Message == nil {
+		return nil, server.NewDecodeError(errNilValue, "Message")
+	}
 	msg, err := s.Message.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Message")
@@ -325,11 +346,14 @@ func (a *AggregateAttestationAndProof) ToConsensus() (*eth.AggregateAttestationA
 	if err != nil {
 		return nil, server.NewDecodeError(err, "AggregatorIndex")
 	}
+	if a.Aggregate == nil {
+		return nil, server.NewDecodeError(errNilValue, "Aggregate")
+	}
 	agg, err := a.Aggregate.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Aggregate")
 	}
-	proof, err := bytesutil.DecodeHexWithLength(a.SelectionProof, 96)
+	proof, err := bytesutil.DecodeHexWithLength(a.SelectionProof, fieldparams.BLSSignatureLength)
 	if err != nil {
 		return nil, server.NewDecodeError(err, "SelectionProof")
 	}
@@ -341,6 +365,9 @@ func (a *AggregateAttestationAndProof) ToConsensus() (*eth.AggregateAttestationA
 }
 
 func (s *SignedAggregateAttestationAndProofElectra) ToConsensus() (*eth.SignedAggregateAttestationAndProofElectra, error) {
+	if s.Message == nil {
+		return nil, server.NewDecodeError(errNilValue, "Message")
+	}
 	msg, err := s.Message.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Message")
@@ -361,11 +388,14 @@ func (a *AggregateAttestationAndProofElectra) ToConsensus() (*eth.AggregateAttes
 	if err != nil {
 		return nil, server.NewDecodeError(err, "AggregatorIndex")
 	}
+	if a.Aggregate == nil {
+		return nil, server.NewDecodeError(errNilValue, "Aggregate")
+	}
 	agg, err := a.Aggregate.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Aggregate")
 	}
-	proof, err := bytesutil.DecodeHexWithLength(a.SelectionProof, 96)
+	proof, err := bytesutil.DecodeHexWithLength(a.SelectionProof, fieldparams.BLSSignatureLength)
 	if err != nil {
 		return nil, server.NewDecodeError(err, "SelectionProof")
 	}
@@ -381,6 +411,9 @@ func (a *Attestation) ToConsensus() (*eth.Attestation, error) {
 	if err != nil {
 		return nil, server.NewDecodeError(err, "AggregationBits")
 	}
+	if a.Data == nil {
+		return nil, server.NewDecodeError(errNilValue, "Data")
+	}
 	data, err := a.Data.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Data")
@@ -410,6 +443,9 @@ func (a *AttestationElectra) ToConsensus() (*eth.AttestationElectra, error) {
 	if err != nil {
 		return nil, server.NewDecodeError(err, "AggregationBits")
 	}
+	if a.Data == nil {
+		return nil, server.NewDecodeError(errNilValue, "Data")
+	}
 	data, err := a.Data.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Data")
@@ -431,6 +467,44 @@ func (a *AttestationElectra) ToConsensus() (*eth.AttestationElectra, error) {
 	}, nil
 }
 
+func SingleAttFromConsensus(a *eth.SingleAttestation) *SingleAttestation {
+	return &SingleAttestation{
+		CommitteeIndex: fmt.Sprintf("%d", a.CommitteeId),
+		AttesterIndex:  fmt.Sprintf("%d", a.AttesterIndex),
+		Data:           AttDataFromConsensus(a.Data),
+		Signature:      hexutil.Encode(a.Signature),
+	}
+}
+
+func (a *SingleAttestation) ToConsensus() (*eth.SingleAttestation, error) {
+	ci, err := strconv.ParseUint(a.CommitteeIndex, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "CommitteeIndex")
+	}
+	ai, err := strconv.ParseUint(a.AttesterIndex, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "AttesterIndex")
+	}
+	if a.Data == nil {
+		return nil, server.NewDecodeError(errNilValue, "Data")
+	}
+	data, err := a.Data.ToConsensus()
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Data")
+	}
+	sig, err := bytesutil.DecodeHexWithLength(a.Signature, fieldparams.BLSSignatureLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Signature")
+	}
+
+	return &eth.SingleAttestation{
+		CommitteeId:   primitives.CommitteeIndex(ci),
+		AttesterIndex: primitives.ValidatorIndex(ai),
+		Data:          data,
+		Signature:     sig,
+	}, nil
+}
+
 func AttElectraFromConsensus(a *eth.AttestationElectra) *AttestationElectra {
 	return &AttestationElectra{
 		AggregationBits: hexutil.Encode(a.AggregationBits),
@@ -453,10 +527,16 @@ func (a *AttestationData) ToConsensus() (*eth.AttestationData, error) {
 	if err != nil {
 		return nil, server.NewDecodeError(err, "BeaconBlockRoot")
 	}
+	if a.Source == nil {
+		return nil, server.NewDecodeError(errNilValue, "Source")
+	}
 	source, err := a.Source.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Source")
 	}
+	if a.Target == nil {
+		return nil, server.NewDecodeError(errNilValue, "Target")
+	}
 	target, err := a.Target.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Target")
@@ -556,15 +636,17 @@ func (b *BeaconCommitteeSubscription) ToConsensus() (*validator.BeaconCommitteeS
 }
 
 func (e *SignedVoluntaryExit) ToConsensus() (*eth.SignedVoluntaryExit, error) {
-	sig, err := bytesutil.DecodeHexWithLength(e.Signature, fieldparams.BLSSignatureLength)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "Signature")
+	if e.Message == nil {
+		return nil, server.NewDecodeError(errNilValue, "Message")
 	}
 	exit, err := e.Message.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Message")
 	}
-
+	sig, err := bytesutil.DecodeHexWithLength(e.Signature, fieldparams.BLSSignatureLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Signature")
+	}
 	return &eth.SignedVoluntaryExit{
 		Exit:      exit,
 		Signature: sig,
@@ -618,6 +700,11 @@ func (m *SyncCommitteeMessage) ToConsensus() (*eth.SyncCommitteeMessage, error)
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Signature")
 	}
+	// Add validation to check if the signature is valid BLS format
+	_, err = bls.SignatureFromBytes(sig)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Signature")
+	}
 
 	return &eth.SyncCommitteeMessage{
 		Slot:           primitives.Slot(slot),
@@ -667,10 +754,16 @@ func Eth1DataFromConsensus(e1d *eth.Eth1Data) *Eth1Data {
 }
 
 func (s *ProposerSlashing) ToConsensus() (*eth.ProposerSlashing, error) {
+	if s.SignedHeader1 == nil {
+		return nil, server.NewDecodeError(errNilValue, "SignedHeader1")
+	}
 	h1, err := s.SignedHeader1.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "SignedHeader1")
 	}
+	if s.SignedHeader2 == nil {
+		return nil, server.NewDecodeError(errNilValue, "SignedHeader2")
+	}
 	h2, err := s.SignedHeader2.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "SignedHeader2")
@@ -683,10 +776,16 @@ func (s *ProposerSlashing) ToConsensus() (*eth.ProposerSlashing, error) {
 }
 
 func (s *AttesterSlashing) ToConsensus() (*eth.AttesterSlashing, error) {
+	if s.Attestation1 == nil {
+		return nil, server.NewDecodeError(errNilValue, "Attestation1")
+	}
 	att1, err := s.Attestation1.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Attestation1")
 	}
+	if s.Attestation2 == nil {
+		return nil, server.NewDecodeError(errNilValue, "Attestation2")
+	}
 	att2, err := s.Attestation2.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Attestation2")
@@ -695,10 +794,16 @@ func (s *AttesterSlashing) ToConsensus() (*eth.AttesterSlashing, error) {
 }
 
 func (s *AttesterSlashingElectra) ToConsensus() (*eth.AttesterSlashingElectra, error) {
+	if s.Attestation1 == nil {
+		return nil, server.NewDecodeError(errNilValue, "Attestation1")
+	}
 	att1, err := s.Attestation1.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Attestation1")
 	}
+	if s.Attestation2 == nil {
+		return nil, server.NewDecodeError(errNilValue, "Attestation2")
+	}
 	att2, err := s.Attestation2.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Attestation2")
@@ -707,6 +812,10 @@ func (s *AttesterSlashingElectra) ToConsensus() (*eth.AttesterSlashingElectra, e
 }
 
 func (a *IndexedAttestation) ToConsensus() (*eth.IndexedAttestation, error) {
+	if err := slice.VerifyMaxLength(a.AttestingIndices, params.BeaconConfig().MaxValidatorsPerCommittee); err != nil {
+		return nil, err
+	}
+
 	indices := make([]uint64, len(a.AttestingIndices))
 	var err error
 	for i, ix := range a.AttestingIndices {
@@ -715,6 +824,9 @@ func (a *IndexedAttestation) ToConsensus() (*eth.IndexedAttestation, error) {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("AttestingIndices[%d]", i))
 		}
 	}
+	if a.Data == nil {
+		return nil, server.NewDecodeError(errNilValue, "Data")
+	}
 	data, err := a.Data.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Data")
@@ -732,6 +844,13 @@ func (a *IndexedAttestation) ToConsensus() (*eth.IndexedAttestation, error) {
 }
 
 func (a *IndexedAttestationElectra) ToConsensus() (*eth.IndexedAttestationElectra, error) {
+	if err := slice.VerifyMaxLength(
+		a.AttestingIndices,
+		params.BeaconConfig().MaxValidatorsPerCommittee*params.BeaconConfig().MaxCommitteesPerSlot,
+	); err != nil {
+		return nil, err
+	}
+
 	indices := make([]uint64, len(a.AttestingIndices))
 	var err error
 	for i, ix := range a.AttestingIndices {
@@ -740,6 +859,9 @@ func (a *IndexedAttestationElectra) ToConsensus() (*eth.IndexedAttestationElectr
 			return nil, server.NewDecodeError(err, fmt.Sprintf("AttestingIndices[%d]", i))
 		}
 	}
+	if a.Data == nil {
+		return nil, server.NewDecodeError(errNilValue, "Data")
+	}
 	data, err := a.Data.ToConsensus()
 	if err != nil {
 		return nil, server.NewDecodeError(err, "Data")
@@ -773,133 +895,13 @@ func WithdrawalFromConsensus(w *enginev1.Withdrawal) *Withdrawal {
 	}
 }
 
-func WithdrawalRequestsFromConsensus(ws []*enginev1.WithdrawalRequest) []*WithdrawalRequest {
-	result := make([]*WithdrawalRequest, len(ws))
-	for i, w := range ws {
-		result[i] = WithdrawalRequestFromConsensus(w)
-	}
-	return result
-}
-
-func WithdrawalRequestFromConsensus(w *enginev1.WithdrawalRequest) *WithdrawalRequest {
-	return &WithdrawalRequest{
-		SourceAddress:   hexutil.Encode(w.SourceAddress),
-		ValidatorPubkey: hexutil.Encode(w.ValidatorPubkey),
-		Amount:          fmt.Sprintf("%d", w.Amount),
-	}
-}
-
-func (w *WithdrawalRequest) ToConsensus() (*enginev1.WithdrawalRequest, error) {
-	src, err := bytesutil.DecodeHexWithLength(w.SourceAddress, common.AddressLength)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "SourceAddress")
-	}
-	pubkey, err := bytesutil.DecodeHexWithLength(w.ValidatorPubkey, fieldparams.BLSPubkeyLength)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "ValidatorPubkey")
-	}
-	amount, err := strconv.ParseUint(w.Amount, 10, 64)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "Amount")
-	}
-	return &enginev1.WithdrawalRequest{
-		SourceAddress:   src,
-		ValidatorPubkey: pubkey,
-		Amount:          amount,
-	}, nil
-}
-
-func ConsolidationRequestsFromConsensus(cs []*enginev1.ConsolidationRequest) []*ConsolidationRequest {
-	result := make([]*ConsolidationRequest, len(cs))
-	for i, c := range cs {
-		result[i] = ConsolidationRequestFromConsensus(c)
-	}
-	return result
-}
-
-func ConsolidationRequestFromConsensus(c *enginev1.ConsolidationRequest) *ConsolidationRequest {
-	return &ConsolidationRequest{
-		SourceAddress: hexutil.Encode(c.SourceAddress),
-		SourcePubkey:  hexutil.Encode(c.SourcePubkey),
-		TargetPubkey:  hexutil.Encode(c.TargetPubkey),
-	}
-}
-
-func (c *ConsolidationRequest) ToConsensus() (*enginev1.ConsolidationRequest, error) {
-	srcAddress, err := bytesutil.DecodeHexWithLength(c.SourceAddress, common.AddressLength)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "SourceAddress")
-	}
-	srcPubkey, err := bytesutil.DecodeHexWithLength(c.SourcePubkey, fieldparams.BLSPubkeyLength)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "SourcePubkey")
-	}
-	targetPubkey, err := bytesutil.DecodeHexWithLength(c.TargetPubkey, fieldparams.BLSPubkeyLength)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "TargetPubkey")
-	}
-	return &enginev1.ConsolidationRequest{
-		SourceAddress: srcAddress,
-		SourcePubkey:  srcPubkey,
-		TargetPubkey:  targetPubkey,
-	}, nil
-}
-
-func DepositRequestsFromConsensus(ds []*enginev1.DepositRequest) []*DepositRequest {
-	result := make([]*DepositRequest, len(ds))
-	for i, d := range ds {
-		result[i] = DepositRequestFromConsensus(d)
-	}
-	return result
-}
-
-func DepositRequestFromConsensus(d *enginev1.DepositRequest) *DepositRequest {
-	return &DepositRequest{
-		Pubkey:                hexutil.Encode(d.Pubkey),
-		WithdrawalCredentials: hexutil.Encode(d.WithdrawalCredentials),
-		Amount:                fmt.Sprintf("%d", d.Amount),
-		Signature:             hexutil.Encode(d.Signature),
-		Index:                 fmt.Sprintf("%d", d.Index),
-	}
-}
-
-func (d *DepositRequest) ToConsensus() (*enginev1.DepositRequest, error) {
-	pubkey, err := bytesutil.DecodeHexWithLength(d.Pubkey, fieldparams.BLSPubkeyLength)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "Pubkey")
-	}
-	withdrawalCredentials, err := bytesutil.DecodeHexWithLength(d.WithdrawalCredentials, fieldparams.RootLength)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "WithdrawalCredentials")
-	}
-	amount, err := strconv.ParseUint(d.Amount, 10, 64)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "Amount")
-	}
-	sig, err := bytesutil.DecodeHexWithLength(d.Signature, fieldparams.BLSSignatureLength)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "Signature")
-	}
-	index, err := strconv.ParseUint(d.Index, 10, 64)
-	if err != nil {
-		return nil, server.NewDecodeError(err, "Index")
-	}
-	return &enginev1.DepositRequest{
-		Pubkey:                pubkey,
-		WithdrawalCredentials: withdrawalCredentials,
-		Amount:                amount,
-		Signature:             sig,
-		Index:                 index,
-	}, nil
-}
-
 func ProposerSlashingsToConsensus(src []*ProposerSlashing) ([]*eth.ProposerSlashing, error) {
 	if src == nil {
-		return nil, errNilValue
+		return nil, server.NewDecodeError(errNilValue, "ProposerSlashings")
 	}
 	err := slice.VerifyMaxLength(src, 16)
 	if err != nil {
-		return nil, err
+		return nil, server.NewDecodeError(err, "ProposerSlashings")
 	}
 	proposerSlashings := make([]*eth.ProposerSlashing, len(src))
 	for i, s := range src {
@@ -1028,11 +1030,11 @@ func ProposerSlashingFromConsensus(src *eth.ProposerSlashing) *ProposerSlashing
 
 func AttesterSlashingsToConsensus(src []*AttesterSlashing) ([]*eth.AttesterSlashing, error) {
 	if src == nil {
-		return nil, errNilValue
+		return nil, server.NewDecodeError(errNilValue, "AttesterSlashings")
 	}
 	err := slice.VerifyMaxLength(src, 2)
 	if err != nil {
-		return nil, err
+		return nil, server.NewDecodeError(err, "AttesterSlashings")
 	}
 
 	attesterSlashings := make([]*eth.AttesterSlashing, len(src))
@@ -1043,10 +1045,19 @@ func AttesterSlashingsToConsensus(src []*AttesterSlashing) ([]*eth.AttesterSlash
 		if s.Attestation1 == nil {
 			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d].Attestation1", i))
 		}
+
+		if s.Attestation1.Data == nil {
+			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d].Attestation1.Data", i))
+		}
+
 		if s.Attestation2 == nil {
 			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d].Attestation2", i))
 		}
 
+		if s.Attestation2.Data == nil {
+			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d].Attestation2.Data", i))
+		}
+
 		a1Sig, err := bytesutil.DecodeHexWithLength(s.Attestation1.Signature, fieldparams.BLSSignatureLength)
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d].Attestation1.Signature", i))
@@ -1063,6 +1074,7 @@ func AttesterSlashingsToConsensus(src []*AttesterSlashing) ([]*eth.AttesterSlash
 			}
 			a1AttestingIndices[j] = attestingIndex
 		}
+
 		a1Data, err := s.Attestation1.Data.ToConsensus()
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d].Attestation1.Data", i))
@@ -1160,11 +1172,11 @@ func AttesterSlashingFromConsensus(src *eth.AttesterSlashing) *AttesterSlashing
 
 func AttesterSlashingsElectraToConsensus(src []*AttesterSlashingElectra) ([]*eth.AttesterSlashingElectra, error) {
 	if src == nil {
-		return nil, errNilValue
+		return nil, server.NewDecodeError(errNilValue, "AttesterSlashingsElectra")
 	}
-	err := slice.VerifyMaxLength(src, 2)
+	err := slice.VerifyMaxLength(src, fieldparams.MaxAttesterSlashingsElectra)
 	if err != nil {
-		return nil, err
+		return nil, server.NewDecodeError(err, "AttesterSlashingsElectra")
 	}
 
 	attesterSlashings := make([]*eth.AttesterSlashingElectra, len(src))
@@ -1172,18 +1184,28 @@ func AttesterSlashingsElectraToConsensus(src []*AttesterSlashingElectra) ([]*eth
 		if s == nil {
 			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d]", i))
 		}
+
 		if s.Attestation1 == nil {
 			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d].Attestation1", i))
 		}
+
+		if s.Attestation1.Data == nil {
+			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d].Attestation1.Data", i))
+		}
+
 		if s.Attestation2 == nil {
 			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d].Attestation2", i))
 		}
 
+		if s.Attestation2.Data == nil {
+			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d].Attestation2.Data", i))
+		}
+
 		a1Sig, err := bytesutil.DecodeHexWithLength(s.Attestation1.Signature, fieldparams.BLSSignatureLength)
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d].Attestation1.Signature", i))
 		}
-		err = slice.VerifyMaxLength(s.Attestation1.AttestingIndices, 2048)
+		err = slice.VerifyMaxLength(s.Attestation1.AttestingIndices, params.BeaconConfig().MaxValidatorsPerCommittee*params.BeaconConfig().MaxCommitteesPerSlot)
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d].Attestation1.AttestingIndices", i))
 		}
@@ -1203,7 +1225,7 @@ func AttesterSlashingsElectraToConsensus(src []*AttesterSlashingElectra) ([]*eth
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d].Attestation2.Signature", i))
 		}
-		err = slice.VerifyMaxLength(s.Attestation2.AttestingIndices, 2048)
+		err = slice.VerifyMaxLength(s.Attestation2.AttestingIndices, params.BeaconConfig().MaxValidatorsPerCommittee*params.BeaconConfig().MaxCommitteesPerSlot)
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d].Attestation2.AttestingIndices", i))
 		}
@@ -1292,15 +1314,18 @@ func AttesterSlashingElectraFromConsensus(src *eth.AttesterSlashingElectra) *Att
 
 func AttsToConsensus(src []*Attestation) ([]*eth.Attestation, error) {
 	if src == nil {
-		return nil, errNilValue
+		return nil, server.NewDecodeError(errNilValue, "Attestations")
 	}
 	err := slice.VerifyMaxLength(src, 128)
 	if err != nil {
-		return nil, err
+		return nil, server.NewDecodeError(err, "Attestations")
 	}
 
 	atts := make([]*eth.Attestation, len(src))
 	for i, a := range src {
+		if a == nil {
+			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d]", i))
+		}
 		atts[i], err = a.ToConsensus()
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d]", i))
@@ -1319,15 +1344,18 @@ func AttsFromConsensus(src []*eth.Attestation) []*Attestation {
 
 func AttsElectraToConsensus(src []*AttestationElectra) ([]*eth.AttestationElectra, error) {
 	if src == nil {
-		return nil, errNilValue
+		return nil, server.NewDecodeError(errNilValue, "AttestationsElectra")
 	}
 	err := slice.VerifyMaxLength(src, 8)
 	if err != nil {
-		return nil, err
+		return nil, server.NewDecodeError(err, "AttestationsElectra")
 	}
 
 	atts := make([]*eth.AttestationElectra, len(src))
 	for i, a := range src {
+		if a == nil {
+			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d]", i))
+		}
 		atts[i], err = a.ToConsensus()
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d]", i))
@@ -1346,11 +1374,11 @@ func AttsElectraFromConsensus(src []*eth.AttestationElectra) []*AttestationElect
 
 func DepositsToConsensus(src []*Deposit) ([]*eth.Deposit, error) {
 	if src == nil {
-		return nil, errNilValue
+		return nil, server.NewDecodeError(errNilValue, "Deposits")
 	}
 	err := slice.VerifyMaxLength(src, 16)
 	if err != nil {
-		return nil, err
+		return nil, server.NewDecodeError(err, "Deposits")
 	}
 
 	deposits := make([]*eth.Deposit, len(src))
@@ -1422,15 +1450,18 @@ func DepositsFromConsensus(src []*eth.Deposit) []*Deposit {
 
 func SignedExitsToConsensus(src []*SignedVoluntaryExit) ([]*eth.SignedVoluntaryExit, error) {
 	if src == nil {
-		return nil, errNilValue
+		return nil, server.NewDecodeError(errNilValue, "SignedVoluntaryExits")
 	}
 	err := slice.VerifyMaxLength(src, 16)
 	if err != nil {
-		return nil, err
+		return nil, server.NewDecodeError(err, "SignedVoluntaryExits")
 	}
 
 	exits := make([]*eth.SignedVoluntaryExit, len(src))
 	for i, e := range src {
+		if e == nil {
+			return nil, server.NewDecodeError(errNilValue, fmt.Sprintf("[%d]", i))
+		}
 		exits[i], err = e.ToConsensus()
 		if err != nil {
 			return nil, server.NewDecodeError(err, fmt.Sprintf("[%d]", i))
@@ -1475,12 +1506,15 @@ func DepositSnapshotFromConsensus(ds *eth.DepositSnapshot) *DepositSnapshot {
 	}
 }
 
-func PendingBalanceDepositsFromConsensus(ds []*eth.PendingBalanceDeposit) []*PendingBalanceDeposit {
-	deposits := make([]*PendingBalanceDeposit, len(ds))
+func PendingDepositsFromConsensus(ds []*eth.PendingDeposit) []*PendingDeposit {
+	deposits := make([]*PendingDeposit, len(ds))
 	for i, d := range ds {
-		deposits[i] = &PendingBalanceDeposit{
-			Index:  fmt.Sprintf("%d", d.Index),
-			Amount: fmt.Sprintf("%d", d.Amount),
+		deposits[i] = &PendingDeposit{
+			Pubkey:                hexutil.Encode(d.PublicKey),
+			WithdrawalCredentials: hexutil.Encode(d.WithdrawalCredentials),
+			Amount:                fmt.Sprintf("%d", d.Amount),
+			Signature:             hexutil.Encode(d.Signature),
+			Slot:                  fmt.Sprintf("%d", d.Slot),
 		}
 	}
 	return deposits
@@ -1508,3 +1542,44 @@ func PendingConsolidationsFromConsensus(cs []*eth.PendingConsolidation) []*Pendi
 	}
 	return consolidations
 }
+
+func HeadEventFromV1(event *ethv1.EventHead) *HeadEvent {
+	return &HeadEvent{
+		Slot:                      fmt.Sprintf("%d", event.Slot),
+		Block:                     hexutil.Encode(event.Block),
+		State:                     hexutil.Encode(event.State),
+		EpochTransition:           event.EpochTransition,
+		ExecutionOptimistic:       event.ExecutionOptimistic,
+		PreviousDutyDependentRoot: hexutil.Encode(event.PreviousDutyDependentRoot),
+		CurrentDutyDependentRoot:  hexutil.Encode(event.CurrentDutyDependentRoot),
+	}
+}
+
+func FinalizedCheckpointEventFromV1(event *ethv1.EventFinalizedCheckpoint) *FinalizedCheckpointEvent {
+	return &FinalizedCheckpointEvent{
+		Block:               hexutil.Encode(event.Block),
+		State:               hexutil.Encode(event.State),
+		Epoch:               fmt.Sprintf("%d", event.Epoch),
+		ExecutionOptimistic: event.ExecutionOptimistic,
+	}
+}
+
+func EventChainReorgFromV1(event *ethv1.EventChainReorg) *ChainReorgEvent {
+	return &ChainReorgEvent{
+		Slot:                fmt.Sprintf("%d", event.Slot),
+		Depth:               fmt.Sprintf("%d", event.Depth),
+		OldHeadBlock:        hexutil.Encode(event.OldHeadBlock),
+		NewHeadBlock:        hexutil.Encode(event.NewHeadBlock),
+		OldHeadState:        hexutil.Encode(event.OldHeadState),
+		NewHeadState:        hexutil.Encode(event.NewHeadState),
+		Epoch:               fmt.Sprintf("%d", event.Epoch),
+		ExecutionOptimistic: event.ExecutionOptimistic,
+	}
+}
+
+func SyncAggregateFromConsensus(sa *eth.SyncAggregate) *SyncAggregate {
+	return &SyncAggregate{
+		SyncCommitteeBits:      hexutil.Encode(sa.SyncCommitteeBits),
+		SyncCommitteeSignature: hexutil.Encode(sa.SyncCommitteeSignature),
+	}
+}

api/server/structs/conversions_blob.go

@@ -0,0 +1,61 @@
+package structs
+
+import (
+	"strconv"
+
+	"github.com/OffchainLabs/prysm/v6/api/server"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	eth "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+)
+
+func (sc *Sidecar) ToConsensus() (*eth.BlobSidecar, error) {
+	if sc == nil {
+		return nil, errNilValue
+	}
+
+	index, err := strconv.ParseUint(sc.Index, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Index")
+	}
+
+	blob, err := bytesutil.DecodeHexWithLength(sc.Blob, 131072)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Blob")
+	}
+
+	kzgCommitment, err := bytesutil.DecodeHexWithLength(sc.KzgCommitment, 48)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "KzgCommitment")
+	}
+
+	kzgProof, err := bytesutil.DecodeHexWithLength(sc.KzgProof, 48)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "KzgProof")
+	}
+
+	header, err := sc.SignedBeaconBlockHeader.ToConsensus()
+	if err != nil {
+		return nil, server.NewDecodeError(err, "SignedBeaconBlockHeader")
+	}
+
+	// decode the commitment inclusion proof
+	var commitmentInclusionProof [][]byte
+	for _, proof := range sc.CommitmentInclusionProof {
+		proofBytes, err := bytesutil.DecodeHexWithLength(proof, 32)
+		if err != nil {
+			return nil, server.NewDecodeError(err, "CommitmentInclusionProof")
+		}
+		commitmentInclusionProof = append(commitmentInclusionProof, proofBytes)
+	}
+
+	bsc := &eth.BlobSidecar{
+		Index:                    index,
+		Blob:                     blob,
+		KzgCommitment:            kzgCommitment,
+		KzgProof:                 kzgProof,
+		SignedBlockHeader:        header,
+		CommitmentInclusionProof: commitmentInclusionProof,
+	}
+
+	return bsc, nil
+}

api/server/structs/conversions_block_execution.go

@@ -0,0 +1,990 @@
+package structs
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/OffchainLabs/prysm/v6/api/server"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	consensusblocks "github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/container/slice"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/pkg/errors"
+	"google.golang.org/protobuf/proto"
+)
+
+// ----------------------------------------------------------------------------
+// Bellatrix
+// ----------------------------------------------------------------------------
+
+func ExecutionPayloadFromConsensus(payload *enginev1.ExecutionPayload) (*ExecutionPayload, error) {
+	baseFeePerGas, err := sszBytesToUint256String(payload.BaseFeePerGas)
+	if err != nil {
+		return nil, err
+	}
+	transactions := make([]string, len(payload.Transactions))
+	for i, tx := range payload.Transactions {
+		transactions[i] = hexutil.Encode(tx)
+	}
+
+	return &ExecutionPayload{
+		ParentHash:    hexutil.Encode(payload.ParentHash),
+		FeeRecipient:  hexutil.Encode(payload.FeeRecipient),
+		StateRoot:     hexutil.Encode(payload.StateRoot),
+		ReceiptsRoot:  hexutil.Encode(payload.ReceiptsRoot),
+		LogsBloom:     hexutil.Encode(payload.LogsBloom),
+		PrevRandao:    hexutil.Encode(payload.PrevRandao),
+		BlockNumber:   fmt.Sprintf("%d", payload.BlockNumber),
+		GasLimit:      fmt.Sprintf("%d", payload.GasLimit),
+		GasUsed:       fmt.Sprintf("%d", payload.GasUsed),
+		Timestamp:     fmt.Sprintf("%d", payload.Timestamp),
+		ExtraData:     hexutil.Encode(payload.ExtraData),
+		BaseFeePerGas: baseFeePerGas,
+		BlockHash:     hexutil.Encode(payload.BlockHash),
+		Transactions:  transactions,
+	}, nil
+}
+
+func (e *ExecutionPayload) ToConsensus() (*enginev1.ExecutionPayload, error) {
+	if e == nil {
+		return nil, server.NewDecodeError(errNilValue, "ExecutionPayload")
+	}
+	payloadParentHash, err := bytesutil.DecodeHexWithLength(e.ParentHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ParentHash")
+	}
+	payloadFeeRecipient, err := bytesutil.DecodeHexWithLength(e.FeeRecipient, fieldparams.FeeRecipientLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.FeeRecipient")
+	}
+	payloadStateRoot, err := bytesutil.DecodeHexWithLength(e.StateRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.StateRoot")
+	}
+	payloadReceiptsRoot, err := bytesutil.DecodeHexWithLength(e.ReceiptsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ReceiptsRoot")
+	}
+	payloadLogsBloom, err := bytesutil.DecodeHexWithLength(e.LogsBloom, fieldparams.LogsBloomLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.LogsBloom")
+	}
+	payloadPrevRandao, err := bytesutil.DecodeHexWithLength(e.PrevRandao, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.PrevRandao")
+	}
+	payloadBlockNumber, err := strconv.ParseUint(e.BlockNumber, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BlockNumber")
+	}
+	payloadGasLimit, err := strconv.ParseUint(e.GasLimit, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.GasLimit")
+	}
+	payloadGasUsed, err := strconv.ParseUint(e.GasUsed, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.GasUsed")
+	}
+	payloadTimestamp, err := strconv.ParseUint(e.Timestamp, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.Timestamp")
+	}
+	payloadExtraData, err := bytesutil.DecodeHexWithMaxLength(e.ExtraData, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ExtraData")
+	}
+	payloadBaseFeePerGas, err := bytesutil.Uint256ToSSZBytes(e.BaseFeePerGas)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BaseFeePerGas")
+	}
+	payloadBlockHash, err := bytesutil.DecodeHexWithLength(e.BlockHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BlockHash")
+	}
+	err = slice.VerifyMaxLength(e.Transactions, fieldparams.MaxTxsPerPayloadLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.Transactions")
+	}
+	payloadTxs := make([][]byte, len(e.Transactions))
+	for i, tx := range e.Transactions {
+		payloadTxs[i], err = bytesutil.DecodeHexWithMaxLength(tx, fieldparams.MaxBytesPerTxLength)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Transactions[%d]", i))
+		}
+	}
+	return &enginev1.ExecutionPayload{
+		ParentHash:    payloadParentHash,
+		FeeRecipient:  payloadFeeRecipient,
+		StateRoot:     payloadStateRoot,
+		ReceiptsRoot:  payloadReceiptsRoot,
+		LogsBloom:     payloadLogsBloom,
+		PrevRandao:    payloadPrevRandao,
+		BlockNumber:   payloadBlockNumber,
+		GasLimit:      payloadGasLimit,
+		GasUsed:       payloadGasUsed,
+		Timestamp:     payloadTimestamp,
+		ExtraData:     payloadExtraData,
+		BaseFeePerGas: payloadBaseFeePerGas,
+		BlockHash:     payloadBlockHash,
+		Transactions:  payloadTxs,
+	}, nil
+}
+
+func (r *ExecutionPayload) PayloadProto() (proto.Message, error) {
+	if r == nil {
+		return nil, errors.Wrap(consensusblocks.ErrNilObject, "nil execution payload")
+	}
+	return r.ToConsensus()
+}
+
+func ExecutionPayloadHeaderFromConsensus(payload *enginev1.ExecutionPayloadHeader) (*ExecutionPayloadHeader, error) {
+	baseFeePerGas, err := sszBytesToUint256String(payload.BaseFeePerGas)
+	if err != nil {
+		return nil, err
+	}
+
+	return &ExecutionPayloadHeader{
+		ParentHash:       hexutil.Encode(payload.ParentHash),
+		FeeRecipient:     hexutil.Encode(payload.FeeRecipient),
+		StateRoot:        hexutil.Encode(payload.StateRoot),
+		ReceiptsRoot:     hexutil.Encode(payload.ReceiptsRoot),
+		LogsBloom:        hexutil.Encode(payload.LogsBloom),
+		PrevRandao:       hexutil.Encode(payload.PrevRandao),
+		BlockNumber:      fmt.Sprintf("%d", payload.BlockNumber),
+		GasLimit:         fmt.Sprintf("%d", payload.GasLimit),
+		GasUsed:          fmt.Sprintf("%d", payload.GasUsed),
+		Timestamp:        fmt.Sprintf("%d", payload.Timestamp),
+		ExtraData:        hexutil.Encode(payload.ExtraData),
+		BaseFeePerGas:    baseFeePerGas,
+		BlockHash:        hexutil.Encode(payload.BlockHash),
+		TransactionsRoot: hexutil.Encode(payload.TransactionsRoot),
+	}, nil
+}
+
+func (e *ExecutionPayloadHeader) ToConsensus() (*enginev1.ExecutionPayloadHeader, error) {
+	if e == nil {
+		return nil, server.NewDecodeError(errNilValue, "ExecutionPayloadHeader")
+	}
+	payloadParentHash, err := bytesutil.DecodeHexWithLength(e.ParentHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.ParentHash")
+	}
+	payloadFeeRecipient, err := bytesutil.DecodeHexWithLength(e.FeeRecipient, fieldparams.FeeRecipientLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.FeeRecipient")
+	}
+	payloadStateRoot, err := bytesutil.DecodeHexWithLength(e.StateRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.StateRoot")
+	}
+	payloadReceiptsRoot, err := bytesutil.DecodeHexWithLength(e.ReceiptsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.ReceiptsRoot")
+	}
+	payloadLogsBloom, err := bytesutil.DecodeHexWithLength(e.LogsBloom, fieldparams.LogsBloomLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.LogsBloom")
+	}
+	payloadPrevRandao, err := bytesutil.DecodeHexWithLength(e.PrevRandao, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.PrevRandao")
+	}
+	payloadBlockNumber, err := strconv.ParseUint(e.BlockNumber, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.BlockNumber")
+	}
+	payloadGasLimit, err := strconv.ParseUint(e.GasLimit, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.GasLimit")
+	}
+	payloadGasUsed, err := strconv.ParseUint(e.GasUsed, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.GasUsed")
+	}
+	payloadTimestamp, err := strconv.ParseUint(e.Timestamp, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.Timestamp")
+	}
+	payloadExtraData, err := bytesutil.DecodeHexWithMaxLength(e.ExtraData, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.ExtraData")
+	}
+	payloadBaseFeePerGas, err := bytesutil.Uint256ToSSZBytes(e.BaseFeePerGas)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.BaseFeePerGas")
+	}
+	payloadBlockHash, err := bytesutil.DecodeHexWithLength(e.BlockHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.BlockHash")
+	}
+	payloadTxsRoot, err := bytesutil.DecodeHexWithLength(e.TransactionsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.TransactionsRoot")
+	}
+
+	return &enginev1.ExecutionPayloadHeader{
+		ParentHash:       payloadParentHash,
+		FeeRecipient:     payloadFeeRecipient,
+		StateRoot:        payloadStateRoot,
+		ReceiptsRoot:     payloadReceiptsRoot,
+		LogsBloom:        payloadLogsBloom,
+		PrevRandao:       payloadPrevRandao,
+		BlockNumber:      payloadBlockNumber,
+		GasLimit:         payloadGasLimit,
+		GasUsed:          payloadGasUsed,
+		Timestamp:        payloadTimestamp,
+		ExtraData:        payloadExtraData,
+		BaseFeePerGas:    payloadBaseFeePerGas,
+		BlockHash:        payloadBlockHash,
+		TransactionsRoot: payloadTxsRoot,
+	}, nil
+}
+
+// ----------------------------------------------------------------------------
+// Capella
+// ----------------------------------------------------------------------------
+
+func ExecutionPayloadCapellaFromConsensus(payload *enginev1.ExecutionPayloadCapella) (*ExecutionPayloadCapella, error) {
+	baseFeePerGas, err := sszBytesToUint256String(payload.BaseFeePerGas)
+	if err != nil {
+		return nil, err
+	}
+	transactions := make([]string, len(payload.Transactions))
+	for i, tx := range payload.Transactions {
+		transactions[i] = hexutil.Encode(tx)
+	}
+
+	return &ExecutionPayloadCapella{
+		ParentHash:    hexutil.Encode(payload.ParentHash),
+		FeeRecipient:  hexutil.Encode(payload.FeeRecipient),
+		StateRoot:     hexutil.Encode(payload.StateRoot),
+		ReceiptsRoot:  hexutil.Encode(payload.ReceiptsRoot),
+		LogsBloom:     hexutil.Encode(payload.LogsBloom),
+		PrevRandao:    hexutil.Encode(payload.PrevRandao),
+		BlockNumber:   fmt.Sprintf("%d", payload.BlockNumber),
+		GasLimit:      fmt.Sprintf("%d", payload.GasLimit),
+		GasUsed:       fmt.Sprintf("%d", payload.GasUsed),
+		Timestamp:     fmt.Sprintf("%d", payload.Timestamp),
+		ExtraData:     hexutil.Encode(payload.ExtraData),
+		BaseFeePerGas: baseFeePerGas,
+		BlockHash:     hexutil.Encode(payload.BlockHash),
+		Transactions:  transactions,
+		Withdrawals:   WithdrawalsFromConsensus(payload.Withdrawals),
+	}, nil
+}
+
+func (e *ExecutionPayloadCapella) ToConsensus() (*enginev1.ExecutionPayloadCapella, error) {
+	if e == nil {
+		return nil, server.NewDecodeError(errNilValue, "ExecutionPayload")
+	}
+	payloadParentHash, err := bytesutil.DecodeHexWithLength(e.ParentHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ParentHash")
+	}
+	payloadFeeRecipient, err := bytesutil.DecodeHexWithLength(e.FeeRecipient, fieldparams.FeeRecipientLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.FeeRecipient")
+	}
+	payloadStateRoot, err := bytesutil.DecodeHexWithLength(e.StateRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.StateRoot")
+	}
+	payloadReceiptsRoot, err := bytesutil.DecodeHexWithLength(e.ReceiptsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ReceiptsRoot")
+	}
+	payloadLogsBloom, err := bytesutil.DecodeHexWithLength(e.LogsBloom, fieldparams.LogsBloomLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.LogsBloom")
+	}
+	payloadPrevRandao, err := bytesutil.DecodeHexWithLength(e.PrevRandao, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.PrevRandao")
+	}
+	payloadBlockNumber, err := strconv.ParseUint(e.BlockNumber, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BlockNumber")
+	}
+	payloadGasLimit, err := strconv.ParseUint(e.GasLimit, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.GasLimit")
+	}
+	payloadGasUsed, err := strconv.ParseUint(e.GasUsed, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.GasUsed")
+	}
+	payloadTimestamp, err := strconv.ParseUint(e.Timestamp, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.Timestamp")
+	}
+	payloadExtraData, err := bytesutil.DecodeHexWithMaxLength(e.ExtraData, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ExtraData")
+	}
+	payloadBaseFeePerGas, err := bytesutil.Uint256ToSSZBytes(e.BaseFeePerGas)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BaseFeePerGas")
+	}
+	payloadBlockHash, err := bytesutil.DecodeHexWithLength(e.BlockHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BlockHash")
+	}
+	err = slice.VerifyMaxLength(e.Transactions, fieldparams.MaxTxsPerPayloadLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.Transactions")
+	}
+	payloadTxs := make([][]byte, len(e.Transactions))
+	for i, tx := range e.Transactions {
+		payloadTxs[i], err = bytesutil.DecodeHexWithMaxLength(tx, fieldparams.MaxBytesPerTxLength)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Transactions[%d]", i))
+		}
+	}
+	err = slice.VerifyMaxLength(e.Withdrawals, fieldparams.MaxWithdrawalsPerPayload)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.Withdrawals")
+	}
+	withdrawals := make([]*enginev1.Withdrawal, len(e.Withdrawals))
+	for i, w := range e.Withdrawals {
+		withdrawalIndex, err := strconv.ParseUint(w.WithdrawalIndex, 10, 64)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Withdrawals[%d].WithdrawalIndex", i))
+		}
+		validatorIndex, err := strconv.ParseUint(w.ValidatorIndex, 10, 64)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Withdrawals[%d].ValidatorIndex", i))
+		}
+		address, err := bytesutil.DecodeHexWithLength(w.ExecutionAddress, common.AddressLength)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Withdrawals[%d].ExecutionAddress", i))
+		}
+		amount, err := strconv.ParseUint(w.Amount, 10, 64)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Withdrawals[%d].Amount", i))
+		}
+		withdrawals[i] = &enginev1.Withdrawal{
+			Index:          withdrawalIndex,
+			ValidatorIndex: primitives.ValidatorIndex(validatorIndex),
+			Address:        address,
+			Amount:         amount,
+		}
+	}
+	return &enginev1.ExecutionPayloadCapella{
+		ParentHash:    payloadParentHash,
+		FeeRecipient:  payloadFeeRecipient,
+		StateRoot:     payloadStateRoot,
+		ReceiptsRoot:  payloadReceiptsRoot,
+		LogsBloom:     payloadLogsBloom,
+		PrevRandao:    payloadPrevRandao,
+		BlockNumber:   payloadBlockNumber,
+		GasLimit:      payloadGasLimit,
+		GasUsed:       payloadGasUsed,
+		Timestamp:     payloadTimestamp,
+		ExtraData:     payloadExtraData,
+		BaseFeePerGas: payloadBaseFeePerGas,
+		BlockHash:     payloadBlockHash,
+		Transactions:  payloadTxs,
+		Withdrawals:   withdrawals,
+	}, nil
+}
+
+func (p *ExecutionPayloadCapella) PayloadProto() (proto.Message, error) {
+	if p == nil {
+		return nil, errors.Wrap(consensusblocks.ErrNilObject, "nil capella execution payload")
+	}
+	return p.ToConsensus()
+}
+
+func ExecutionPayloadHeaderCapellaFromConsensus(payload *enginev1.ExecutionPayloadHeaderCapella) (*ExecutionPayloadHeaderCapella, error) {
+	baseFeePerGas, err := sszBytesToUint256String(payload.BaseFeePerGas)
+	if err != nil {
+		return nil, err
+	}
+
+	return &ExecutionPayloadHeaderCapella{
+		ParentHash:       hexutil.Encode(payload.ParentHash),
+		FeeRecipient:     hexutil.Encode(payload.FeeRecipient),
+		StateRoot:        hexutil.Encode(payload.StateRoot),
+		ReceiptsRoot:     hexutil.Encode(payload.ReceiptsRoot),
+		LogsBloom:        hexutil.Encode(payload.LogsBloom),
+		PrevRandao:       hexutil.Encode(payload.PrevRandao),
+		BlockNumber:      fmt.Sprintf("%d", payload.BlockNumber),
+		GasLimit:         fmt.Sprintf("%d", payload.GasLimit),
+		GasUsed:          fmt.Sprintf("%d", payload.GasUsed),
+		Timestamp:        fmt.Sprintf("%d", payload.Timestamp),
+		ExtraData:        hexutil.Encode(payload.ExtraData),
+		BaseFeePerGas:    baseFeePerGas,
+		BlockHash:        hexutil.Encode(payload.BlockHash),
+		TransactionsRoot: hexutil.Encode(payload.TransactionsRoot),
+		WithdrawalsRoot:  hexutil.Encode(payload.WithdrawalsRoot),
+	}, nil
+}
+
+func (e *ExecutionPayloadHeaderCapella) ToConsensus() (*enginev1.ExecutionPayloadHeaderCapella, error) {
+	if e == nil {
+		return nil, server.NewDecodeError(errNilValue, "ExecutionPayloadHeader")
+	}
+	payloadParentHash, err := bytesutil.DecodeHexWithLength(e.ParentHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.ParentHash")
+	}
+	payloadFeeRecipient, err := bytesutil.DecodeHexWithLength(e.FeeRecipient, fieldparams.FeeRecipientLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.FeeRecipient")
+	}
+	payloadStateRoot, err := bytesutil.DecodeHexWithLength(e.StateRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.StateRoot")
+	}
+	payloadReceiptsRoot, err := bytesutil.DecodeHexWithLength(e.ReceiptsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.ReceiptsRoot")
+	}
+	payloadLogsBloom, err := bytesutil.DecodeHexWithLength(e.LogsBloom, fieldparams.LogsBloomLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.LogsBloom")
+	}
+	payloadPrevRandao, err := bytesutil.DecodeHexWithLength(e.PrevRandao, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.PrevRandao")
+	}
+	payloadBlockNumber, err := strconv.ParseUint(e.BlockNumber, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.BlockNumber")
+	}
+	payloadGasLimit, err := strconv.ParseUint(e.GasLimit, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.GasLimit")
+	}
+	payloadGasUsed, err := strconv.ParseUint(e.GasUsed, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.GasUsed")
+	}
+	payloadTimestamp, err := strconv.ParseUint(e.Timestamp, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.Timestamp")
+	}
+	payloadExtraData, err := bytesutil.DecodeHexWithMaxLength(e.ExtraData, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.ExtraData")
+	}
+	payloadBaseFeePerGas, err := bytesutil.Uint256ToSSZBytes(e.BaseFeePerGas)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.BaseFeePerGas")
+	}
+	payloadBlockHash, err := bytesutil.DecodeHexWithMaxLength(e.BlockHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.BlockHash")
+	}
+	payloadTxsRoot, err := bytesutil.DecodeHexWithMaxLength(e.TransactionsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.TransactionsRoot")
+	}
+	payloadWithdrawalsRoot, err := bytesutil.DecodeHexWithMaxLength(e.WithdrawalsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.WithdrawalsRoot")
+	}
+	return &enginev1.ExecutionPayloadHeaderCapella{
+		ParentHash:       payloadParentHash,
+		FeeRecipient:     payloadFeeRecipient,
+		StateRoot:        payloadStateRoot,
+		ReceiptsRoot:     payloadReceiptsRoot,
+		LogsBloom:        payloadLogsBloom,
+		PrevRandao:       payloadPrevRandao,
+		BlockNumber:      payloadBlockNumber,
+		GasLimit:         payloadGasLimit,
+		GasUsed:          payloadGasUsed,
+		Timestamp:        payloadTimestamp,
+		ExtraData:        payloadExtraData,
+		BaseFeePerGas:    payloadBaseFeePerGas,
+		BlockHash:        payloadBlockHash,
+		TransactionsRoot: payloadTxsRoot,
+		WithdrawalsRoot:  payloadWithdrawalsRoot,
+	}, nil
+}
+
+// ----------------------------------------------------------------------------
+// Deneb
+// ----------------------------------------------------------------------------
+
+func ExecutionPayloadDenebFromConsensus(payload *enginev1.ExecutionPayloadDeneb) (*ExecutionPayloadDeneb, error) {
+	baseFeePerGas, err := sszBytesToUint256String(payload.BaseFeePerGas)
+	if err != nil {
+		return nil, err
+	}
+	transactions := make([]string, len(payload.Transactions))
+	for i, tx := range payload.Transactions {
+		transactions[i] = hexutil.Encode(tx)
+	}
+
+	return &ExecutionPayloadDeneb{
+		ParentHash:    hexutil.Encode(payload.ParentHash),
+		FeeRecipient:  hexutil.Encode(payload.FeeRecipient),
+		StateRoot:     hexutil.Encode(payload.StateRoot),
+		ReceiptsRoot:  hexutil.Encode(payload.ReceiptsRoot),
+		LogsBloom:     hexutil.Encode(payload.LogsBloom),
+		PrevRandao:    hexutil.Encode(payload.PrevRandao),
+		BlockNumber:   fmt.Sprintf("%d", payload.BlockNumber),
+		GasLimit:      fmt.Sprintf("%d", payload.GasLimit),
+		GasUsed:       fmt.Sprintf("%d", payload.GasUsed),
+		Timestamp:     fmt.Sprintf("%d", payload.Timestamp),
+		ExtraData:     hexutil.Encode(payload.ExtraData),
+		BaseFeePerGas: baseFeePerGas,
+		BlockHash:     hexutil.Encode(payload.BlockHash),
+		Transactions:  transactions,
+		Withdrawals:   WithdrawalsFromConsensus(payload.Withdrawals),
+		BlobGasUsed:   fmt.Sprintf("%d", payload.BlobGasUsed),
+		ExcessBlobGas: fmt.Sprintf("%d", payload.ExcessBlobGas),
+	}, nil
+}
+
+func (e *ExecutionPayloadDeneb) ToConsensus() (*enginev1.ExecutionPayloadDeneb, error) {
+	if e == nil {
+		return nil, server.NewDecodeError(errNilValue, "ExecutionPayload")
+	}
+	payloadParentHash, err := bytesutil.DecodeHexWithLength(e.ParentHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ParentHash")
+	}
+	payloadFeeRecipient, err := bytesutil.DecodeHexWithLength(e.FeeRecipient, fieldparams.FeeRecipientLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.FeeRecipient")
+	}
+	payloadStateRoot, err := bytesutil.DecodeHexWithLength(e.StateRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.StateRoot")
+	}
+	payloadReceiptsRoot, err := bytesutil.DecodeHexWithLength(e.ReceiptsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ReceiptsRoot")
+	}
+	payloadLogsBloom, err := bytesutil.DecodeHexWithLength(e.LogsBloom, fieldparams.LogsBloomLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.LogsBloom")
+	}
+	payloadPrevRandao, err := bytesutil.DecodeHexWithLength(e.PrevRandao, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.PrevRandao")
+	}
+	payloadBlockNumber, err := strconv.ParseUint(e.BlockNumber, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BlockNumber")
+	}
+	payloadGasLimit, err := strconv.ParseUint(e.GasLimit, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.GasLimit")
+	}
+	payloadGasUsed, err := strconv.ParseUint(e.GasUsed, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.GasUsed")
+	}
+	payloadTimestamp, err := strconv.ParseUint(e.Timestamp, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.Timestamp")
+	}
+	payloadExtraData, err := bytesutil.DecodeHexWithMaxLength(e.ExtraData, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ExtraData")
+	}
+	payloadBaseFeePerGas, err := bytesutil.Uint256ToSSZBytes(e.BaseFeePerGas)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BaseFeePerGas")
+	}
+	payloadBlockHash, err := bytesutil.DecodeHexWithLength(e.BlockHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BlockHash")
+	}
+	err = slice.VerifyMaxLength(e.Transactions, fieldparams.MaxTxsPerPayloadLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.Transactions")
+	}
+	txs := make([][]byte, len(e.Transactions))
+	for i, tx := range e.Transactions {
+		txs[i], err = bytesutil.DecodeHexWithMaxLength(tx, fieldparams.MaxBytesPerTxLength)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Transactions[%d]", i))
+		}
+	}
+	err = slice.VerifyMaxLength(e.Withdrawals, fieldparams.MaxWithdrawalsPerPayload)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.Withdrawals")
+	}
+	withdrawals := make([]*enginev1.Withdrawal, len(e.Withdrawals))
+	for i, w := range e.Withdrawals {
+		withdrawalIndex, err := strconv.ParseUint(w.WithdrawalIndex, 10, 64)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Withdrawals[%d].WithdrawalIndex", i))
+		}
+		validatorIndex, err := strconv.ParseUint(w.ValidatorIndex, 10, 64)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Withdrawals[%d].ValidatorIndex", i))
+		}
+		address, err := bytesutil.DecodeHexWithLength(w.ExecutionAddress, common.AddressLength)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Withdrawals[%d].ExecutionAddress", i))
+		}
+		amount, err := strconv.ParseUint(w.Amount, 10, 64)
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionPayload.Withdrawals[%d].Amount", i))
+		}
+		withdrawals[i] = &enginev1.Withdrawal{
+			Index:          withdrawalIndex,
+			ValidatorIndex: primitives.ValidatorIndex(validatorIndex),
+			Address:        address,
+			Amount:         amount,
+		}
+	}
+
+	payloadBlobGasUsed, err := strconv.ParseUint(e.BlobGasUsed, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BlobGasUsed")
+	}
+	payloadExcessBlobGas, err := strconv.ParseUint(e.ExcessBlobGas, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ExcessBlobGas")
+	}
+	return &enginev1.ExecutionPayloadDeneb{
+		ParentHash:    payloadParentHash,
+		FeeRecipient:  payloadFeeRecipient,
+		StateRoot:     payloadStateRoot,
+		ReceiptsRoot:  payloadReceiptsRoot,
+		LogsBloom:     payloadLogsBloom,
+		PrevRandao:    payloadPrevRandao,
+		BlockNumber:   payloadBlockNumber,
+		GasLimit:      payloadGasLimit,
+		GasUsed:       payloadGasUsed,
+		Timestamp:     payloadTimestamp,
+		ExtraData:     payloadExtraData,
+		BaseFeePerGas: payloadBaseFeePerGas,
+		BlockHash:     payloadBlockHash,
+		Transactions:  txs,
+		Withdrawals:   withdrawals,
+		BlobGasUsed:   payloadBlobGasUsed,
+		ExcessBlobGas: payloadExcessBlobGas,
+	}, nil
+}
+
+func ExecutionPayloadHeaderDenebFromConsensus(payload *enginev1.ExecutionPayloadHeaderDeneb) (*ExecutionPayloadHeaderDeneb, error) {
+	baseFeePerGas, err := sszBytesToUint256String(payload.BaseFeePerGas)
+	if err != nil {
+		return nil, err
+	}
+
+	return &ExecutionPayloadHeaderDeneb{
+		ParentHash:       hexutil.Encode(payload.ParentHash),
+		FeeRecipient:     hexutil.Encode(payload.FeeRecipient),
+		StateRoot:        hexutil.Encode(payload.StateRoot),
+		ReceiptsRoot:     hexutil.Encode(payload.ReceiptsRoot),
+		LogsBloom:        hexutil.Encode(payload.LogsBloom),
+		PrevRandao:       hexutil.Encode(payload.PrevRandao),
+		BlockNumber:      fmt.Sprintf("%d", payload.BlockNumber),
+		GasLimit:         fmt.Sprintf("%d", payload.GasLimit),
+		GasUsed:          fmt.Sprintf("%d", payload.GasUsed),
+		Timestamp:        fmt.Sprintf("%d", payload.Timestamp),
+		ExtraData:        hexutil.Encode(payload.ExtraData),
+		BaseFeePerGas:    baseFeePerGas,
+		BlockHash:        hexutil.Encode(payload.BlockHash),
+		TransactionsRoot: hexutil.Encode(payload.TransactionsRoot),
+		WithdrawalsRoot:  hexutil.Encode(payload.WithdrawalsRoot),
+		BlobGasUsed:      fmt.Sprintf("%d", payload.BlobGasUsed),
+		ExcessBlobGas:    fmt.Sprintf("%d", payload.ExcessBlobGas),
+	}, nil
+}
+
+func (e *ExecutionPayloadHeaderDeneb) ToConsensus() (*enginev1.ExecutionPayloadHeaderDeneb, error) {
+	if e == nil {
+		return nil, server.NewDecodeError(errNilValue, "ExecutionPayloadHeader")
+	}
+	payloadParentHash, err := bytesutil.DecodeHexWithLength(e.ParentHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.ParentHash")
+	}
+	payloadFeeRecipient, err := bytesutil.DecodeHexWithLength(e.FeeRecipient, fieldparams.FeeRecipientLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.FeeRecipient")
+	}
+	payloadStateRoot, err := bytesutil.DecodeHexWithLength(e.StateRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.StateRoot")
+	}
+	payloadReceiptsRoot, err := bytesutil.DecodeHexWithLength(e.ReceiptsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.ReceiptsRoot")
+	}
+	payloadLogsBloom, err := bytesutil.DecodeHexWithLength(e.LogsBloom, fieldparams.LogsBloomLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.LogsBloom")
+	}
+	payloadPrevRandao, err := bytesutil.DecodeHexWithLength(e.PrevRandao, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.PrevRandao")
+	}
+	payloadBlockNumber, err := strconv.ParseUint(e.BlockNumber, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.BlockNumber")
+	}
+	payloadGasLimit, err := strconv.ParseUint(e.GasLimit, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.GasLimit")
+	}
+	payloadGasUsed, err := strconv.ParseUint(e.GasUsed, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.GasUsed")
+	}
+	payloadTimestamp, err := strconv.ParseUint(e.Timestamp, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.Timestamp")
+	}
+	payloadExtraData, err := bytesutil.DecodeHexWithMaxLength(e.ExtraData, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.ExtraData")
+	}
+	payloadBaseFeePerGas, err := bytesutil.Uint256ToSSZBytes(e.BaseFeePerGas)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.BaseFeePerGas")
+	}
+	payloadBlockHash, err := bytesutil.DecodeHexWithLength(e.BlockHash, common.HashLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.BlockHash")
+	}
+	payloadTxsRoot, err := bytesutil.DecodeHexWithLength(e.TransactionsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.TransactionsRoot")
+	}
+	payloadWithdrawalsRoot, err := bytesutil.DecodeHexWithLength(e.WithdrawalsRoot, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayloadHeader.WithdrawalsRoot")
+	}
+	payloadBlobGasUsed, err := strconv.ParseUint(e.BlobGasUsed, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.BlobGasUsed")
+	}
+	payloadExcessBlobGas, err := strconv.ParseUint(e.ExcessBlobGas, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ExecutionPayload.ExcessBlobGas")
+	}
+	return &enginev1.ExecutionPayloadHeaderDeneb{
+		ParentHash:       payloadParentHash,
+		FeeRecipient:     payloadFeeRecipient,
+		StateRoot:        payloadStateRoot,
+		ReceiptsRoot:     payloadReceiptsRoot,
+		LogsBloom:        payloadLogsBloom,
+		PrevRandao:       payloadPrevRandao,
+		BlockNumber:      payloadBlockNumber,
+		GasLimit:         payloadGasLimit,
+		GasUsed:          payloadGasUsed,
+		Timestamp:        payloadTimestamp,
+		ExtraData:        payloadExtraData,
+		BaseFeePerGas:    payloadBaseFeePerGas,
+		BlockHash:        payloadBlockHash,
+		TransactionsRoot: payloadTxsRoot,
+		WithdrawalsRoot:  payloadWithdrawalsRoot,
+		BlobGasUsed:      payloadBlobGasUsed,
+		ExcessBlobGas:    payloadExcessBlobGas,
+	}, nil
+}
+
+// ----------------------------------------------------------------------------
+// Electra
+// ----------------------------------------------------------------------------
+
+var (
+	ExecutionPayloadElectraFromConsensus       = ExecutionPayloadDenebFromConsensus
+	ExecutionPayloadHeaderElectraFromConsensus = ExecutionPayloadHeaderDenebFromConsensus
+)
+
+func WithdrawalRequestsFromConsensus(ws []*enginev1.WithdrawalRequest) []*WithdrawalRequest {
+	result := make([]*WithdrawalRequest, len(ws))
+	for i, w := range ws {
+		result[i] = WithdrawalRequestFromConsensus(w)
+	}
+	return result
+}
+
+func WithdrawalRequestFromConsensus(w *enginev1.WithdrawalRequest) *WithdrawalRequest {
+	return &WithdrawalRequest{
+		SourceAddress:   hexutil.Encode(w.SourceAddress),
+		ValidatorPubkey: hexutil.Encode(w.ValidatorPubkey),
+		Amount:          fmt.Sprintf("%d", w.Amount),
+	}
+}
+
+func (w *WithdrawalRequest) ToConsensus() (*enginev1.WithdrawalRequest, error) {
+	if w == nil {
+		return nil, server.NewDecodeError(errNilValue, "WithdrawalRequest")
+	}
+	src, err := bytesutil.DecodeHexWithLength(w.SourceAddress, common.AddressLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "SourceAddress")
+	}
+	pubkey, err := bytesutil.DecodeHexWithLength(w.ValidatorPubkey, fieldparams.BLSPubkeyLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "ValidatorPubkey")
+	}
+	amount, err := strconv.ParseUint(w.Amount, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Amount")
+	}
+	return &enginev1.WithdrawalRequest{
+		SourceAddress:   src,
+		ValidatorPubkey: pubkey,
+		Amount:          amount,
+	}, nil
+}
+
+func ConsolidationRequestsFromConsensus(cs []*enginev1.ConsolidationRequest) []*ConsolidationRequest {
+	result := make([]*ConsolidationRequest, len(cs))
+	for i, c := range cs {
+		result[i] = ConsolidationRequestFromConsensus(c)
+	}
+	return result
+}
+
+func ConsolidationRequestFromConsensus(c *enginev1.ConsolidationRequest) *ConsolidationRequest {
+	return &ConsolidationRequest{
+		SourceAddress: hexutil.Encode(c.SourceAddress),
+		SourcePubkey:  hexutil.Encode(c.SourcePubkey),
+		TargetPubkey:  hexutil.Encode(c.TargetPubkey),
+	}
+}
+
+func (c *ConsolidationRequest) ToConsensus() (*enginev1.ConsolidationRequest, error) {
+	if c == nil {
+		return nil, server.NewDecodeError(errNilValue, "ConsolidationRequest")
+	}
+	srcAddress, err := bytesutil.DecodeHexWithLength(c.SourceAddress, common.AddressLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "SourceAddress")
+	}
+	srcPubkey, err := bytesutil.DecodeHexWithLength(c.SourcePubkey, fieldparams.BLSPubkeyLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "SourcePubkey")
+	}
+	targetPubkey, err := bytesutil.DecodeHexWithLength(c.TargetPubkey, fieldparams.BLSPubkeyLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "TargetPubkey")
+	}
+	return &enginev1.ConsolidationRequest{
+		SourceAddress: srcAddress,
+		SourcePubkey:  srcPubkey,
+		TargetPubkey:  targetPubkey,
+	}, nil
+}
+
+func DepositRequestsFromConsensus(ds []*enginev1.DepositRequest) []*DepositRequest {
+	result := make([]*DepositRequest, len(ds))
+	for i, d := range ds {
+		result[i] = DepositRequestFromConsensus(d)
+	}
+	return result
+}
+
+func DepositRequestFromConsensus(d *enginev1.DepositRequest) *DepositRequest {
+	return &DepositRequest{
+		Pubkey:                hexutil.Encode(d.Pubkey),
+		WithdrawalCredentials: hexutil.Encode(d.WithdrawalCredentials),
+		Amount:                fmt.Sprintf("%d", d.Amount),
+		Signature:             hexutil.Encode(d.Signature),
+		Index:                 fmt.Sprintf("%d", d.Index),
+	}
+}
+
+func (d *DepositRequest) ToConsensus() (*enginev1.DepositRequest, error) {
+	if d == nil {
+		return nil, server.NewDecodeError(errNilValue, "DepositRequest")
+	}
+	pubkey, err := bytesutil.DecodeHexWithLength(d.Pubkey, fieldparams.BLSPubkeyLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Pubkey")
+	}
+	withdrawalCredentials, err := bytesutil.DecodeHexWithLength(d.WithdrawalCredentials, fieldparams.RootLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "WithdrawalCredentials")
+	}
+	amount, err := strconv.ParseUint(d.Amount, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Amount")
+	}
+	sig, err := bytesutil.DecodeHexWithLength(d.Signature, fieldparams.BLSSignatureLength)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Signature")
+	}
+	index, err := strconv.ParseUint(d.Index, 10, 64)
+	if err != nil {
+		return nil, server.NewDecodeError(err, "Index")
+	}
+	return &enginev1.DepositRequest{
+		Pubkey:                pubkey,
+		WithdrawalCredentials: withdrawalCredentials,
+		Amount:                amount,
+		Signature:             sig,
+		Index:                 index,
+	}, nil
+}
+
+func ExecutionRequestsFromConsensus(er *enginev1.ExecutionRequests) *ExecutionRequests {
+	return &ExecutionRequests{
+		Deposits:       DepositRequestsFromConsensus(er.Deposits),
+		Withdrawals:    WithdrawalRequestsFromConsensus(er.Withdrawals),
+		Consolidations: ConsolidationRequestsFromConsensus(er.Consolidations),
+	}
+}
+
+func (e *ExecutionRequests) ToConsensus() (*enginev1.ExecutionRequests, error) {
+	if e == nil {
+		return nil, server.NewDecodeError(errNilValue, "ExecutionRequests")
+	}
+	var err error
+	if err = slice.VerifyMaxLength(e.Deposits, params.BeaconConfig().MaxDepositRequestsPerPayload); err != nil {
+		return nil, err
+	}
+	depositRequests := make([]*enginev1.DepositRequest, len(e.Deposits))
+	for i, d := range e.Deposits {
+		depositRequests[i], err = d.ToConsensus()
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionRequests.Deposits[%d]", i))
+		}
+	}
+
+	if err = slice.VerifyMaxLength(e.Withdrawals, params.BeaconConfig().MaxWithdrawalRequestsPerPayload); err != nil {
+		return nil, err
+	}
+	withdrawalRequests := make([]*enginev1.WithdrawalRequest, len(e.Withdrawals))
+	for i, w := range e.Withdrawals {
+		withdrawalRequests[i], err = w.ToConsensus()
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionRequests.Withdrawals[%d]", i))
+		}
+	}
+
+	if err = slice.VerifyMaxLength(e.Consolidations, params.BeaconConfig().MaxConsolidationsRequestsPerPayload); err != nil {
+		return nil, err
+	}
+	consolidationRequests := make([]*enginev1.ConsolidationRequest, len(e.Consolidations))
+	for i, c := range e.Consolidations {
+		consolidationRequests[i], err = c.ToConsensus()
+		if err != nil {
+			return nil, server.NewDecodeError(err, fmt.Sprintf("ExecutionRequests.Consolidations[%d]", i))
+		}
+	}
+	return &enginev1.ExecutionRequests{
+		Deposits:       depositRequests,
+		Withdrawals:    withdrawalRequests,
+		Consolidations: consolidationRequests,
+	}, nil
+}
+
+// ----------------------------------------------------------------------------
+// Fulu
+// ----------------------------------------------------------------------------
+
+var (
+	ExecutionPayloadFuluFromConsensus       = ExecutionPayloadDenebFromConsensus
+	ExecutionPayloadHeaderFuluFromConsensus = ExecutionPayloadHeaderDenebFromConsensus
+	BeaconBlockFuluFromConsensus            = BeaconBlockElectraFromConsensus
+)

api/server/structs/conversions_block_execution_test.go

@@ -0,0 +1,563 @@
+package structs
+
+import (
+	"fmt"
+	"testing"
+
+	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+)
+
+func fillByteSlice(sliceLength int, value byte) []byte {
+	bytes := make([]byte, sliceLength)
+
+	for index := range bytes {
+		bytes[index] = value
+	}
+
+	return bytes
+}
+
+// TestExecutionPayloadFromConsensus_HappyPath checks the
+// ExecutionPayloadFromConsensus function under normal conditions.
+func TestExecutionPayloadFromConsensus_HappyPath(t *testing.T) {
+	consensusPayload := &enginev1.ExecutionPayload{
+		ParentHash:    fillByteSlice(common.HashLength, 0xaa),
+		FeeRecipient:  fillByteSlice(20, 0xbb),
+		StateRoot:     fillByteSlice(32, 0xcc),
+		ReceiptsRoot:  fillByteSlice(32, 0xdd),
+		LogsBloom:     fillByteSlice(256, 0xee),
+		PrevRandao:    fillByteSlice(32, 0xff),
+		BlockNumber:   12345,
+		GasLimit:      15000000,
+		GasUsed:       8000000,
+		Timestamp:     1680000000,
+		ExtraData:     fillByteSlice(8, 0x11),
+		BaseFeePerGas: fillByteSlice(32, 0x01),
+		BlockHash:     fillByteSlice(common.HashLength, 0x22),
+		Transactions: [][]byte{
+			fillByteSlice(10, 0x33),
+			fillByteSlice(10, 0x44),
+		},
+	}
+
+	result, err := ExecutionPayloadFromConsensus(consensusPayload)
+	require.NoError(t, err)
+	require.NotNil(t, result)
+	require.Equal(t, hexutil.Encode(consensusPayload.ParentHash), result.ParentHash)
+	require.Equal(t, hexutil.Encode(consensusPayload.FeeRecipient), result.FeeRecipient)
+	require.Equal(t, hexutil.Encode(consensusPayload.StateRoot), result.StateRoot)
+	require.Equal(t, hexutil.Encode(consensusPayload.ReceiptsRoot), result.ReceiptsRoot)
+	require.Equal(t, fmt.Sprintf("%d", consensusPayload.BlockNumber), result.BlockNumber)
+}
+
+// TestExecutionPayload_ToConsensus_HappyPath checks the
+// (*ExecutionPayload).ToConsensus function under normal conditions.
+func TestExecutionPayload_ToConsensus_HappyPath(t *testing.T) {
+	payload := &ExecutionPayload{
+		ParentHash:    hexutil.Encode(fillByteSlice(common.HashLength, 0xaa)),
+		FeeRecipient:  hexutil.Encode(fillByteSlice(20, 0xbb)),
+		StateRoot:     hexutil.Encode(fillByteSlice(32, 0xcc)),
+		ReceiptsRoot:  hexutil.Encode(fillByteSlice(32, 0xdd)),
+		LogsBloom:     hexutil.Encode(fillByteSlice(256, 0xee)),
+		PrevRandao:    hexutil.Encode(fillByteSlice(32, 0xff)),
+		BlockNumber:   "12345",
+		GasLimit:      "15000000",
+		GasUsed:       "8000000",
+		Timestamp:     "1680000000",
+		ExtraData:     "0x11111111",
+		BaseFeePerGas: "1234",
+		BlockHash:     hexutil.Encode(fillByteSlice(common.HashLength, 0x22)),
+		Transactions: []string{
+			hexutil.Encode(fillByteSlice(10, 0x33)),
+			hexutil.Encode(fillByteSlice(10, 0x44)),
+		},
+	}
+
+	result, err := payload.ToConsensus()
+	require.NoError(t, err)
+	require.DeepEqual(t, result.ParentHash, fillByteSlice(common.HashLength, 0xaa))
+	require.DeepEqual(t, result.FeeRecipient, fillByteSlice(20, 0xbb))
+	require.DeepEqual(t, result.StateRoot, fillByteSlice(32, 0xcc))
+}
+
+// TestExecutionPayloadHeaderFromConsensus_HappyPath checks the
+// ExecutionPayloadHeaderFromConsensus function under normal conditions.
+func TestExecutionPayloadHeaderFromConsensus_HappyPath(t *testing.T) {
+	consensusHeader := &enginev1.ExecutionPayloadHeader{
+		ParentHash:       fillByteSlice(common.HashLength, 0xaa),
+		FeeRecipient:     fillByteSlice(20, 0xbb),
+		StateRoot:        fillByteSlice(32, 0xcc),
+		ReceiptsRoot:     fillByteSlice(32, 0xdd),
+		LogsBloom:        fillByteSlice(256, 0xee),
+		PrevRandao:       fillByteSlice(32, 0xff),
+		BlockNumber:      9999,
+		GasLimit:         5000000,
+		GasUsed:          2500000,
+		Timestamp:        1111111111,
+		ExtraData:        fillByteSlice(4, 0x12),
+		BaseFeePerGas:    fillByteSlice(32, 0x34),
+		BlockHash:        fillByteSlice(common.HashLength, 0x56),
+		TransactionsRoot: fillByteSlice(32, 0x78),
+	}
+
+	result, err := ExecutionPayloadHeaderFromConsensus(consensusHeader)
+	require.NoError(t, err)
+	require.NotNil(t, result)
+	require.Equal(t, hexutil.Encode(consensusHeader.ParentHash), result.ParentHash)
+	require.Equal(t, fmt.Sprintf("%d", consensusHeader.BlockNumber), result.BlockNumber)
+}
+
+// TestExecutionPayloadHeader_ToConsensus_HappyPath checks the
+// (*ExecutionPayloadHeader).ToConsensus function under normal conditions.
+func TestExecutionPayloadHeader_ToConsensus_HappyPath(t *testing.T) {
+	header := &ExecutionPayloadHeader{
+		ParentHash:       hexutil.Encode(fillByteSlice(common.HashLength, 0xaa)),
+		FeeRecipient:     hexutil.Encode(fillByteSlice(20, 0xbb)),
+		StateRoot:        hexutil.Encode(fillByteSlice(32, 0xcc)),
+		ReceiptsRoot:     hexutil.Encode(fillByteSlice(32, 0xdd)),
+		LogsBloom:        hexutil.Encode(fillByteSlice(256, 0xee)),
+		PrevRandao:       hexutil.Encode(fillByteSlice(32, 0xff)),
+		BlockNumber:      "9999",
+		GasLimit:         "5000000",
+		GasUsed:          "2500000",
+		Timestamp:        "1111111111",
+		ExtraData:        "0x1234abcd",
+		BaseFeePerGas:    "1234",
+		BlockHash:        hexutil.Encode(fillByteSlice(common.HashLength, 0x56)),
+		TransactionsRoot: hexutil.Encode(fillByteSlice(32, 0x78)),
+	}
+
+	result, err := header.ToConsensus()
+	require.NoError(t, err)
+	require.DeepEqual(t, hexutil.Encode(result.ParentHash), header.ParentHash)
+	require.DeepEqual(t, hexutil.Encode(result.FeeRecipient), header.FeeRecipient)
+	require.DeepEqual(t, hexutil.Encode(result.StateRoot), header.StateRoot)
+}
+
+// TestExecutionPayloadCapellaFromConsensus_HappyPath checks the
+// ExecutionPayloadCapellaFromConsensus function under normal conditions.
+func TestExecutionPayloadCapellaFromConsensus_HappyPath(t *testing.T) {
+	capellaPayload := &enginev1.ExecutionPayloadCapella{
+		ParentHash:    fillByteSlice(common.HashLength, 0xaa),
+		FeeRecipient:  fillByteSlice(20, 0xbb),
+		StateRoot:     fillByteSlice(32, 0xcc),
+		ReceiptsRoot:  fillByteSlice(32, 0xdd),
+		LogsBloom:     fillByteSlice(256, 0xee),
+		PrevRandao:    fillByteSlice(32, 0xff),
+		BlockNumber:   123,
+		GasLimit:      9876543,
+		GasUsed:       1234567,
+		Timestamp:     5555555,
+		ExtraData:     fillByteSlice(6, 0x11),
+		BaseFeePerGas: fillByteSlice(32, 0x22),
+		BlockHash:     fillByteSlice(common.HashLength, 0x33),
+		Transactions: [][]byte{
+			fillByteSlice(5, 0x44),
+		},
+		Withdrawals: []*enginev1.Withdrawal{
+			{
+				Index:          1,
+				ValidatorIndex: 2,
+				Address:        fillByteSlice(20, 0xaa),
+				Amount:         100,
+			},
+		},
+	}
+
+	result, err := ExecutionPayloadCapellaFromConsensus(capellaPayload)
+	require.NoError(t, err)
+	require.NotNil(t, result)
+	require.Equal(t, hexutil.Encode(capellaPayload.ParentHash), result.ParentHash)
+	require.Equal(t, len(capellaPayload.Transactions), len(result.Transactions))
+	require.Equal(t, len(capellaPayload.Withdrawals), len(result.Withdrawals))
+}
+
+// TestExecutionPayloadCapella_ToConsensus_HappyPath checks the
+// (*ExecutionPayloadCapella).ToConsensus function under normal conditions.
+func TestExecutionPayloadCapella_ToConsensus_HappyPath(t *testing.T) {
+	capella := &ExecutionPayloadCapella{
+		ParentHash:    hexutil.Encode(fillByteSlice(common.HashLength, 0xaa)),
+		FeeRecipient:  hexutil.Encode(fillByteSlice(20, 0xbb)),
+		StateRoot:     hexutil.Encode(fillByteSlice(32, 0xcc)),
+		ReceiptsRoot:  hexutil.Encode(fillByteSlice(32, 0xdd)),
+		LogsBloom:     hexutil.Encode(fillByteSlice(256, 0xee)),
+		PrevRandao:    hexutil.Encode(fillByteSlice(32, 0xff)),
+		BlockNumber:   "123",
+		GasLimit:      "9876543",
+		GasUsed:       "1234567",
+		Timestamp:     "5555555",
+		ExtraData:     hexutil.Encode(fillByteSlice(6, 0x11)),
+		BaseFeePerGas: "1234",
+		BlockHash:     hexutil.Encode(fillByteSlice(common.HashLength, 0x33)),
+		Transactions: []string{
+			hexutil.Encode(fillByteSlice(5, 0x44)),
+		},
+		Withdrawals: []*Withdrawal{
+			{
+				WithdrawalIndex:  "1",
+				ValidatorIndex:   "2",
+				ExecutionAddress: hexutil.Encode(fillByteSlice(20, 0xaa)),
+				Amount:           "100",
+			},
+		},
+	}
+
+	result, err := capella.ToConsensus()
+	require.NoError(t, err)
+	require.DeepEqual(t, hexutil.Encode(result.ParentHash), capella.ParentHash)
+	require.DeepEqual(t, hexutil.Encode(result.FeeRecipient), capella.FeeRecipient)
+	require.DeepEqual(t, hexutil.Encode(result.StateRoot), capella.StateRoot)
+}
+
+// TestExecutionPayloadDenebFromConsensus_HappyPath checks the
+// ExecutionPayloadDenebFromConsensus function under normal conditions.
+func TestExecutionPayloadDenebFromConsensus_HappyPath(t *testing.T) {
+	denebPayload := &enginev1.ExecutionPayloadDeneb{
+		ParentHash:    fillByteSlice(common.HashLength, 0xaa),
+		FeeRecipient:  fillByteSlice(20, 0xbb),
+		StateRoot:     fillByteSlice(32, 0xcc),
+		ReceiptsRoot:  fillByteSlice(32, 0xdd),
+		LogsBloom:     fillByteSlice(256, 0xee),
+		PrevRandao:    fillByteSlice(32, 0xff),
+		BlockNumber:   999,
+		GasLimit:      2222222,
+		GasUsed:       1111111,
+		Timestamp:     666666,
+		ExtraData:     fillByteSlice(6, 0x11),
+		BaseFeePerGas: fillByteSlice(32, 0x22),
+		BlockHash:     fillByteSlice(common.HashLength, 0x33),
+		Transactions: [][]byte{
+			fillByteSlice(5, 0x44),
+		},
+		Withdrawals: []*enginev1.Withdrawal{
+			{
+				Index:          1,
+				ValidatorIndex: 2,
+				Address:        fillByteSlice(20, 0xaa),
+				Amount:         100,
+			},
+		},
+		BlobGasUsed:   1234,
+		ExcessBlobGas: 5678,
+	}
+
+	result, err := ExecutionPayloadDenebFromConsensus(denebPayload)
+	require.NoError(t, err)
+	require.Equal(t, hexutil.Encode(denebPayload.ParentHash), result.ParentHash)
+	require.Equal(t, len(denebPayload.Transactions), len(result.Transactions))
+	require.Equal(t, len(denebPayload.Withdrawals), len(result.Withdrawals))
+	require.Equal(t, "1234", result.BlobGasUsed)
+	require.Equal(t, fmt.Sprintf("%d", denebPayload.BlockNumber), result.BlockNumber)
+}
+
+// TestExecutionPayloadDeneb_ToConsensus_HappyPath checks the
+// (*ExecutionPayloadDeneb).ToConsensus function under normal conditions.
+func TestExecutionPayloadDeneb_ToConsensus_HappyPath(t *testing.T) {
+	deneb := &ExecutionPayloadDeneb{
+		ParentHash:    hexutil.Encode(fillByteSlice(common.HashLength, 0xaa)),
+		FeeRecipient:  hexutil.Encode(fillByteSlice(20, 0xbb)),
+		StateRoot:     hexutil.Encode(fillByteSlice(32, 0xcc)),
+		ReceiptsRoot:  hexutil.Encode(fillByteSlice(32, 0xdd)),
+		LogsBloom:     hexutil.Encode(fillByteSlice(256, 0xee)),
+		PrevRandao:    hexutil.Encode(fillByteSlice(32, 0xff)),
+		BlockNumber:   "999",
+		GasLimit:      "2222222",
+		GasUsed:       "1111111",
+		Timestamp:     "666666",
+		ExtraData:     hexutil.Encode(fillByteSlice(6, 0x11)),
+		BaseFeePerGas: "1234",
+		BlockHash:     hexutil.Encode(fillByteSlice(common.HashLength, 0x33)),
+		Transactions: []string{
+			hexutil.Encode(fillByteSlice(5, 0x44)),
+		},
+		Withdrawals: []*Withdrawal{
+			{
+				WithdrawalIndex:  "1",
+				ValidatorIndex:   "2",
+				ExecutionAddress: hexutil.Encode(fillByteSlice(20, 0xaa)),
+				Amount:           "100",
+			},
+		},
+		BlobGasUsed:   "1234",
+		ExcessBlobGas: "5678",
+	}
+
+	result, err := deneb.ToConsensus()
+	require.NoError(t, err)
+	require.DeepEqual(t, hexutil.Encode(result.ParentHash), deneb.ParentHash)
+	require.DeepEqual(t, hexutil.Encode(result.FeeRecipient), deneb.FeeRecipient)
+	require.Equal(t, result.BlockNumber, uint64(999))
+}
+
+func TestExecutionPayloadHeaderCapellaFromConsensus_HappyPath(t *testing.T) {
+	capellaHeader := &enginev1.ExecutionPayloadHeaderCapella{
+		ParentHash:       fillByteSlice(common.HashLength, 0xaa),
+		FeeRecipient:     fillByteSlice(20, 0xbb),
+		StateRoot:        fillByteSlice(32, 0xcc),
+		ReceiptsRoot:     fillByteSlice(32, 0xdd),
+		LogsBloom:        fillByteSlice(256, 0xee),
+		PrevRandao:       fillByteSlice(32, 0xff),
+		BlockNumber:      555,
+		GasLimit:         1111111,
+		GasUsed:          222222,
+		Timestamp:        3333333333,
+		ExtraData:        fillByteSlice(4, 0x12),
+		BaseFeePerGas:    fillByteSlice(32, 0x34),
+		BlockHash:        fillByteSlice(common.HashLength, 0x56),
+		TransactionsRoot: fillByteSlice(32, 0x78),
+		WithdrawalsRoot:  fillByteSlice(32, 0x99),
+	}
+
+	result, err := ExecutionPayloadHeaderCapellaFromConsensus(capellaHeader)
+	require.NoError(t, err)
+	require.Equal(t, hexutil.Encode(capellaHeader.ParentHash), result.ParentHash)
+	require.DeepEqual(t, hexutil.Encode(capellaHeader.WithdrawalsRoot), result.WithdrawalsRoot)
+}
+
+func TestExecutionPayloadHeaderCapella_ToConsensus_HappyPath(t *testing.T) {
+	header := &ExecutionPayloadHeaderCapella{
+		ParentHash:       hexutil.Encode(fillByteSlice(common.HashLength, 0xaa)),
+		FeeRecipient:     hexutil.Encode(fillByteSlice(20, 0xbb)),
+		StateRoot:        hexutil.Encode(fillByteSlice(32, 0xcc)),
+		ReceiptsRoot:     hexutil.Encode(fillByteSlice(32, 0xdd)),
+		LogsBloom:        hexutil.Encode(fillByteSlice(256, 0xee)),
+		PrevRandao:       hexutil.Encode(fillByteSlice(32, 0xff)),
+		BlockNumber:      "555",
+		GasLimit:         "1111111",
+		GasUsed:          "222222",
+		Timestamp:        "3333333333",
+		ExtraData:        "0x1234abcd",
+		BaseFeePerGas:    "1234",
+		BlockHash:        hexutil.Encode(fillByteSlice(common.HashLength, 0x56)),
+		TransactionsRoot: hexutil.Encode(fillByteSlice(32, 0x78)),
+		WithdrawalsRoot:  hexutil.Encode(fillByteSlice(32, 0x99)),
+	}
+
+	result, err := header.ToConsensus()
+	require.NoError(t, err)
+	require.DeepEqual(t, hexutil.Encode(result.ParentHash), header.ParentHash)
+	require.DeepEqual(t, hexutil.Encode(result.FeeRecipient), header.FeeRecipient)
+	require.DeepEqual(t, hexutil.Encode(result.StateRoot), header.StateRoot)
+	require.DeepEqual(t, hexutil.Encode(result.ReceiptsRoot), header.ReceiptsRoot)
+	require.DeepEqual(t, hexutil.Encode(result.WithdrawalsRoot), header.WithdrawalsRoot)
+}
+
+func TestExecutionPayloadHeaderDenebFromConsensus_HappyPath(t *testing.T) {
+	denebHeader := &enginev1.ExecutionPayloadHeaderDeneb{
+		ParentHash:       fillByteSlice(common.HashLength, 0xaa),
+		FeeRecipient:     fillByteSlice(20, 0xbb),
+		StateRoot:        fillByteSlice(32, 0xcc),
+		ReceiptsRoot:     fillByteSlice(32, 0xdd),
+		LogsBloom:        fillByteSlice(256, 0xee),
+		PrevRandao:       fillByteSlice(32, 0xff),
+		BlockNumber:      999,
+		GasLimit:         5000000,
+		GasUsed:          2500000,
+		Timestamp:        4444444444,
+		ExtraData:        fillByteSlice(4, 0x12),
+		BaseFeePerGas:    fillByteSlice(32, 0x34),
+		BlockHash:        fillByteSlice(common.HashLength, 0x56),
+		TransactionsRoot: fillByteSlice(32, 0x78),
+		WithdrawalsRoot:  fillByteSlice(32, 0x99),
+		BlobGasUsed:      1234,
+		ExcessBlobGas:    5678,
+	}
+
+	result, err := ExecutionPayloadHeaderDenebFromConsensus(denebHeader)
+	require.NoError(t, err)
+	require.Equal(t, hexutil.Encode(denebHeader.ParentHash), result.ParentHash)
+	require.DeepEqual(t, hexutil.Encode(denebHeader.FeeRecipient), result.FeeRecipient)
+	require.DeepEqual(t, hexutil.Encode(denebHeader.StateRoot), result.StateRoot)
+	require.DeepEqual(t, fmt.Sprintf("%d", denebHeader.BlobGasUsed), result.BlobGasUsed)
+}
+
+func TestExecutionPayloadHeaderDeneb_ToConsensus_HappyPath(t *testing.T) {
+	header := &ExecutionPayloadHeaderDeneb{
+		ParentHash:       hexutil.Encode(fillByteSlice(common.HashLength, 0xaa)),
+		FeeRecipient:     hexutil.Encode(fillByteSlice(20, 0xbb)),
+		StateRoot:        hexutil.Encode(fillByteSlice(32, 0xcc)),
+		ReceiptsRoot:     hexutil.Encode(fillByteSlice(32, 0xdd)),
+		LogsBloom:        hexutil.Encode(fillByteSlice(256, 0xee)),
+		PrevRandao:       hexutil.Encode(fillByteSlice(32, 0xff)),
+		BlockNumber:      "999",
+		GasLimit:         "5000000",
+		GasUsed:          "2500000",
+		Timestamp:        "4444444444",
+		ExtraData:        "0x1234abcd",
+		BaseFeePerGas:    "1234",
+		BlockHash:        hexutil.Encode(fillByteSlice(common.HashLength, 0x56)),
+		TransactionsRoot: hexutil.Encode(fillByteSlice(32, 0x78)),
+		WithdrawalsRoot:  hexutil.Encode(fillByteSlice(32, 0x99)),
+		BlobGasUsed:      "1234",
+		ExcessBlobGas:    "5678",
+	}
+
+	result, err := header.ToConsensus()
+	require.NoError(t, err)
+	require.DeepEqual(t, hexutil.Encode(result.ParentHash), header.ParentHash)
+	require.DeepEqual(t, result.BlobGasUsed, uint64(1234))
+	require.DeepEqual(t, result.ExcessBlobGas, uint64(5678))
+	require.DeepEqual(t, result.BlockNumber, uint64(999))
+}
+
+func TestWithdrawalRequestsFromConsensus_HappyPath(t *testing.T) {
+	consensusRequests := []*enginev1.WithdrawalRequest{
+		{
+			SourceAddress:   fillByteSlice(20, 0xbb),
+			ValidatorPubkey: fillByteSlice(48, 0xbb),
+			Amount:          12345,
+		},
+		{
+			SourceAddress:   fillByteSlice(20, 0xcc),
+			ValidatorPubkey: fillByteSlice(48, 0xcc),
+			Amount:          54321,
+		},
+	}
+
+	result := WithdrawalRequestsFromConsensus(consensusRequests)
+	require.DeepEqual(t, len(result), len(consensusRequests))
+	require.DeepEqual(t, result[0].Amount, fmt.Sprintf("%d", consensusRequests[0].Amount))
+}
+
+func TestWithdrawalRequestFromConsensus_HappyPath(t *testing.T) {
+	req := &enginev1.WithdrawalRequest{
+		SourceAddress:   fillByteSlice(20, 0xbb),
+		ValidatorPubkey: fillByteSlice(48, 0xbb),
+		Amount:          42,
+	}
+	result := WithdrawalRequestFromConsensus(req)
+	require.NotNil(t, result)
+	require.DeepEqual(t, result.SourceAddress, hexutil.Encode(fillByteSlice(20, 0xbb)))
+}
+
+func TestWithdrawalRequest_ToConsensus_HappyPath(t *testing.T) {
+	withdrawalReq := &WithdrawalRequest{
+		SourceAddress:   hexutil.Encode(fillByteSlice(20, 111)),
+		ValidatorPubkey: hexutil.Encode(fillByteSlice(48, 123)),
+		Amount:          "12345",
+	}
+	result, err := withdrawalReq.ToConsensus()
+	require.NoError(t, err)
+	require.DeepEqual(t, result.Amount, uint64(12345))
+}
+
+func TestConsolidationRequestsFromConsensus_HappyPath(t *testing.T) {
+	consensusRequests := []*enginev1.ConsolidationRequest{
+		{
+			SourceAddress: fillByteSlice(20, 111),
+			SourcePubkey:  fillByteSlice(48, 112),
+			TargetPubkey:  fillByteSlice(48, 113),
+		},
+	}
+	result := ConsolidationRequestsFromConsensus(consensusRequests)
+	require.DeepEqual(t, len(result), len(consensusRequests))
+	require.DeepEqual(t, result[0].SourceAddress, "0x6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f6f")
+}
+
+func TestDepositRequestsFromConsensus_HappyPath(t *testing.T) {
+	ds := []*enginev1.DepositRequest{
+		{
+			Pubkey:                fillByteSlice(48, 0xbb),
+			WithdrawalCredentials: fillByteSlice(32, 0xdd),
+			Amount:                98765,
+			Signature:             fillByteSlice(96, 0xff),
+			Index:                 111,
+		},
+	}
+	result := DepositRequestsFromConsensus(ds)
+	require.DeepEqual(t, len(result), len(ds))
+	require.DeepEqual(t, result[0].Amount, "98765")
+}
+
+func TestDepositRequest_ToConsensus_HappyPath(t *testing.T) {
+	req := &DepositRequest{
+		Pubkey:                hexutil.Encode(fillByteSlice(48, 0xbb)),
+		WithdrawalCredentials: hexutil.Encode(fillByteSlice(32, 0xaa)),
+		Amount:                "123",
+		Signature:             hexutil.Encode(fillByteSlice(96, 0xdd)),
+		Index:                 "456",
+	}
+
+	result, err := req.ToConsensus()
+	require.NoError(t, err)
+	require.DeepEqual(t, result.Amount, uint64(123))
+	require.DeepEqual(t, result.Signature, fillByteSlice(96, 0xdd))
+}
+
+func TestExecutionRequestsFromConsensus_HappyPath(t *testing.T) {
+	er := &enginev1.ExecutionRequests{
+		Deposits: []*enginev1.DepositRequest{
+			{
+				Pubkey:                fillByteSlice(48, 0xba),
+				WithdrawalCredentials: fillByteSlice(32, 0xaa),
+				Amount:                33,
+				Signature:             fillByteSlice(96, 0xff),
+				Index:                 44,
+			},
+		},
+		Withdrawals: []*enginev1.WithdrawalRequest{
+			{
+				SourceAddress:   fillByteSlice(20, 0xaa),
+				ValidatorPubkey: fillByteSlice(48, 0xba),
+				Amount:          555,
+			},
+		},
+		Consolidations: []*enginev1.ConsolidationRequest{
+			{
+				SourceAddress: fillByteSlice(20, 0xdd),
+				SourcePubkey:  fillByteSlice(48, 0xdd),
+				TargetPubkey:  fillByteSlice(48, 0xcc),
+			},
+		},
+	}
+
+	result := ExecutionRequestsFromConsensus(er)
+	require.NotNil(t, result)
+	require.Equal(t, 1, len(result.Deposits))
+	require.Equal(t, "33", result.Deposits[0].Amount)
+	require.Equal(t, 1, len(result.Withdrawals))
+	require.Equal(t, "555", result.Withdrawals[0].Amount)
+	require.Equal(t, 1, len(result.Consolidations))
+	require.Equal(t, "0xcccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc", result.Consolidations[0].TargetPubkey)
+}
+
+func TestExecutionRequests_ToConsensus_HappyPath(t *testing.T) {
+	execReq := &ExecutionRequests{
+		Deposits: []*DepositRequest{
+			{
+				Pubkey:                hexutil.Encode(fillByteSlice(48, 0xbb)),
+				WithdrawalCredentials: hexutil.Encode(fillByteSlice(32, 0xaa)),
+				Amount:                "33",
+				Signature:             hexutil.Encode(fillByteSlice(96, 0xff)),
+				Index:                 "44",
+			},
+		},
+		Withdrawals: []*WithdrawalRequest{
+			{
+				SourceAddress:   hexutil.Encode(fillByteSlice(20, 0xdd)),
+				ValidatorPubkey: hexutil.Encode(fillByteSlice(48, 0xbb)),
+				Amount:          "555",
+			},
+		},
+		Consolidations: []*ConsolidationRequest{
+			{
+				SourceAddress: hexutil.Encode(fillByteSlice(20, 0xcc)),
+				SourcePubkey:  hexutil.Encode(fillByteSlice(48, 0xbb)),
+				TargetPubkey:  hexutil.Encode(fillByteSlice(48, 0xcc)),
+			},
+		},
+	}
+
+	result, err := execReq.ToConsensus()
+	require.NoError(t, err)
+
+	require.Equal(t, 1, len(result.Deposits))
+	require.Equal(t, uint64(33), result.Deposits[0].Amount)
+	require.Equal(t, 1, len(result.Withdrawals))
+	require.Equal(t, uint64(555), result.Withdrawals[0].Amount)
+	require.Equal(t, 1, len(result.Consolidations))
+	require.DeepEqual(t, fillByteSlice(48, 0xcc), result.Consolidations[0].TargetPubkey)
+}

api/server/structs/conversions_lightclient.go

@@ -0,0 +1,229 @@
+package structs
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
+	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/pkg/errors"
+)
+
+func LightClientUpdateFromConsensus(update interfaces.LightClientUpdate) (*LightClientUpdate, error) {
+	attestedHeader, err := lightClientHeaderToJSON(update.AttestedHeader())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not marshal attested light client header")
+	}
+	finalizedHeader, err := lightClientHeaderToJSON(update.FinalizedHeader())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not marshal finalized light client header")
+	}
+
+	var scBranch [][32]byte
+	var finalityBranch [][32]byte
+	if update.Version() >= version.Electra {
+		scb, err := update.NextSyncCommitteeBranchElectra()
+		if err != nil {
+			return nil, err
+		}
+		scBranch = scb[:]
+		fb, err := update.FinalityBranchElectra()
+		if err != nil {
+			return nil, err
+		}
+		finalityBranch = fb[:]
+	} else {
+		scb, err := update.NextSyncCommitteeBranch()
+		if err != nil {
+			return nil, err
+		}
+		scBranch = scb[:]
+		fb, err := update.FinalityBranch()
+		if err != nil {
+			return nil, err
+		}
+		finalityBranch = fb[:]
+	}
+
+	return &LightClientUpdate{
+		AttestedHeader:          attestedHeader,
+		NextSyncCommittee:       SyncCommitteeFromConsensus(update.NextSyncCommittee()),
+		NextSyncCommitteeBranch: branchToJSON(scBranch),
+		FinalizedHeader:         finalizedHeader,
+		FinalityBranch:          branchToJSON(finalityBranch),
+		SyncAggregate:           SyncAggregateFromConsensus(update.SyncAggregate()),
+		SignatureSlot:           fmt.Sprintf("%d", update.SignatureSlot()),
+	}, nil
+}
+
+func LightClientFinalityUpdateFromConsensus(update interfaces.LightClientFinalityUpdate) (*LightClientFinalityUpdate, error) {
+	attestedHeader, err := lightClientHeaderToJSON(update.AttestedHeader())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not marshal attested light client header")
+	}
+	finalizedHeader, err := lightClientHeaderToJSON(update.FinalizedHeader())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not marshal finalized light client header")
+	}
+
+	var finalityBranch [][32]byte
+	if update.Version() >= version.Electra {
+		b, err := update.FinalityBranchElectra()
+		if err != nil {
+			return nil, err
+		}
+		finalityBranch = b[:]
+	} else {
+		b, err := update.FinalityBranch()
+		if err != nil {
+			return nil, err
+		}
+		finalityBranch = b[:]
+	}
+
+	return &LightClientFinalityUpdate{
+		AttestedHeader:  attestedHeader,
+		FinalizedHeader: finalizedHeader,
+		FinalityBranch:  branchToJSON(finalityBranch),
+		SyncAggregate:   SyncAggregateFromConsensus(update.SyncAggregate()),
+		SignatureSlot:   fmt.Sprintf("%d", update.SignatureSlot()),
+	}, nil
+}
+
+func LightClientOptimisticUpdateFromConsensus(update interfaces.LightClientOptimisticUpdate) (*LightClientOptimisticUpdate, error) {
+	attestedHeader, err := lightClientHeaderToJSON(update.AttestedHeader())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not marshal attested light client header")
+	}
+
+	return &LightClientOptimisticUpdate{
+		AttestedHeader: attestedHeader,
+		SyncAggregate:  SyncAggregateFromConsensus(update.SyncAggregate()),
+		SignatureSlot:  fmt.Sprintf("%d", update.SignatureSlot()),
+	}, nil
+}
+
+func branchToJSON[S [][32]byte](branchBytes S) []string {
+	if branchBytes == nil {
+		return nil
+	}
+	branch := make([]string, len(branchBytes))
+	for i, root := range branchBytes {
+		branch[i] = hexutil.Encode(root[:])
+	}
+	return branch
+}
+
+func lightClientHeaderToJSON(header interfaces.LightClientHeader) (json.RawMessage, error) {
+	// In the case that a finalizedHeader is nil.
+	if header == nil {
+		return nil, nil
+	}
+
+	var result any
+
+	switch v := header.Version(); v {
+	case version.Altair:
+		result = &LightClientHeader{Beacon: BeaconBlockHeaderFromConsensus(header.Beacon())}
+	case version.Capella:
+		exInterface, err := header.Execution()
+		if err != nil {
+			return nil, err
+		}
+		ex, ok := exInterface.Proto().(*enginev1.ExecutionPayloadHeaderCapella)
+		if !ok {
+			return nil, fmt.Errorf("execution data is not %T", &enginev1.ExecutionPayloadHeaderCapella{})
+		}
+		execution, err := ExecutionPayloadHeaderCapellaFromConsensus(ex)
+		if err != nil {
+			return nil, err
+		}
+		executionBranch, err := header.ExecutionBranch()
+		if err != nil {
+			return nil, err
+		}
+		result = &LightClientHeaderCapella{
+			Beacon:          BeaconBlockHeaderFromConsensus(header.Beacon()),
+			Execution:       execution,
+			ExecutionBranch: branchToJSON(executionBranch[:]),
+		}
+	case version.Deneb:
+		exInterface, err := header.Execution()
+		if err != nil {
+			return nil, err
+		}
+		ex, ok := exInterface.Proto().(*enginev1.ExecutionPayloadHeaderDeneb)
+		if !ok {
+			return nil, fmt.Errorf("execution data is not %T", &enginev1.ExecutionPayloadHeaderDeneb{})
+		}
+		execution, err := ExecutionPayloadHeaderDenebFromConsensus(ex)
+		if err != nil {
+			return nil, err
+		}
+		executionBranch, err := header.ExecutionBranch()
+		if err != nil {
+			return nil, err
+		}
+		result = &LightClientHeaderDeneb{
+			Beacon:          BeaconBlockHeaderFromConsensus(header.Beacon()),
+			Execution:       execution,
+			ExecutionBranch: branchToJSON(executionBranch[:]),
+		}
+	case version.Electra:
+		exInterface, err := header.Execution()
+		if err != nil {
+			return nil, err
+		}
+		ex, ok := exInterface.Proto().(*enginev1.ExecutionPayloadHeaderDeneb)
+		if !ok {
+			return nil, fmt.Errorf("execution data is not %T", &enginev1.ExecutionPayloadHeaderDeneb{})
+		}
+		execution, err := ExecutionPayloadHeaderElectraFromConsensus(ex)
+		if err != nil {
+			return nil, err
+		}
+		executionBranch, err := header.ExecutionBranch()
+		if err != nil {
+			return nil, err
+		}
+		result = &LightClientHeaderDeneb{
+			Beacon:          BeaconBlockHeaderFromConsensus(header.Beacon()),
+			Execution:       execution,
+			ExecutionBranch: branchToJSON(executionBranch[:]),
+		}
+	default:
+		return nil, fmt.Errorf("unsupported header version %s", version.String(v))
+	}
+
+	return json.Marshal(result)
+}
+
+func LightClientBootstrapFromConsensus(bootstrap interfaces.LightClientBootstrap) (*LightClientBootstrap, error) {
+	header, err := lightClientHeaderToJSON(bootstrap.Header())
+	if err != nil {
+		return nil, errors.Wrap(err, "could not marshal light client header")
+	}
+
+	var scBranch [][32]byte
+	if bootstrap.Version() >= version.Electra {
+		b, err := bootstrap.CurrentSyncCommitteeBranchElectra()
+		if err != nil {
+			return nil, err
+		}
+		scBranch = b[:]
+	} else {
+		b, err := bootstrap.CurrentSyncCommitteeBranch()
+		if err != nil {
+			return nil, err
+		}
+		scBranch = b[:]
+	}
+
+	return &LightClientBootstrap{
+		Header:                     header,
+		CurrentSyncCommittee:       SyncCommitteeFromConsensus(bootstrap.CurrentSyncCommittee()),
+		CurrentSyncCommitteeBranch: branchToJSON(scBranch),
+	}, nil
+}

api/server/structs/conversions_state.go

@@ -4,13 +4,17 @@ import (
 	"errors"
 	"fmt"
 
+	beaconState "github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
 	"github.com/ethereum/go-ethereum/common/hexutil"
-	beaconState "github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
 )
 
 var errPayloadHeaderNotFound = errors.New("expected payload header not found")
 
+// ----------------------------------------------------------------------------
+// Phase 0
+// ----------------------------------------------------------------------------
+
 func BeaconStateFromConsensus(st beaconState.BeaconState) (*BeaconState, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -22,10 +26,7 @@ func BeaconStateFromConsensus(st beaconState.BeaconState) (*BeaconState, error)
 	for i, r := range srcSr {
 		sr[i] = hexutil.Encode(r)
 	}
-	srcHr, err := st.HistoricalRoots()
-	if err != nil {
-		return nil, err
-	}
+	srcHr := st.HistoricalRoots()
 	hr := make([]string, len(srcHr))
 	for i, r := range srcHr {
 		hr[i] = hexutil.Encode(r)
@@ -73,7 +74,7 @@ func BeaconStateFromConsensus(st beaconState.BeaconState) (*BeaconState, error)
 	}
 
 	return &BeaconState{
-		GenesisTime:                 fmt.Sprintf("%d", st.GenesisTime()),
+		GenesisTime:                 fmt.Sprintf("%d", st.GenesisTime().Unix()),
 		GenesisValidatorsRoot:       hexutil.Encode(st.GenesisValidatorsRoot()),
 		Slot:                        fmt.Sprintf("%d", st.Slot()),
 		Fork:                        ForkFromConsensus(st.Fork()),
@@ -97,6 +98,10 @@ func BeaconStateFromConsensus(st beaconState.BeaconState) (*BeaconState, error)
 	}, nil
 }
 
+// ----------------------------------------------------------------------------
+// Altair
+// ----------------------------------------------------------------------------
+
 func BeaconStateAltairFromConsensus(st beaconState.BeaconState) (*BeaconStateAltair, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -108,10 +113,7 @@ func BeaconStateAltairFromConsensus(st beaconState.BeaconState) (*BeaconStateAlt
 	for i, r := range srcSr {
 		sr[i] = hexutil.Encode(r)
 	}
-	srcHr, err := st.HistoricalRoots()
-	if err != nil {
-		return nil, err
-	}
+	srcHr := st.HistoricalRoots()
 	hr := make([]string, len(srcHr))
 	for i, r := range srcHr {
 		hr[i] = hexutil.Encode(r)
@@ -175,7 +177,7 @@ func BeaconStateAltairFromConsensus(st beaconState.BeaconState) (*BeaconStateAlt
 	}
 
 	return &BeaconStateAltair{
-		GenesisTime:                 fmt.Sprintf("%d", st.GenesisTime()),
+		GenesisTime:                 fmt.Sprintf("%d", st.GenesisTime().Unix()),
 		GenesisValidatorsRoot:       hexutil.Encode(st.GenesisValidatorsRoot()),
 		Slot:                        fmt.Sprintf("%d", st.Slot()),
 		Fork:                        ForkFromConsensus(st.Fork()),
@@ -202,6 +204,10 @@ func BeaconStateAltairFromConsensus(st beaconState.BeaconState) (*BeaconStateAlt
 	}, nil
 }
 
+// ----------------------------------------------------------------------------
+// Bellatrix
+// ----------------------------------------------------------------------------
+
 func BeaconStateBellatrixFromConsensus(st beaconState.BeaconState) (*BeaconStateBellatrix, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -213,10 +219,7 @@ func BeaconStateBellatrixFromConsensus(st beaconState.BeaconState) (*BeaconState
 	for i, r := range srcSr {
 		sr[i] = hexutil.Encode(r)
 	}
-	srcHr, err := st.HistoricalRoots()
-	if err != nil {
-		return nil, err
-	}
+	srcHr := st.HistoricalRoots()
 	hr := make([]string, len(srcHr))
 	for i, r := range srcHr {
 		hr[i] = hexutil.Encode(r)
@@ -292,7 +295,7 @@ func BeaconStateBellatrixFromConsensus(st beaconState.BeaconState) (*BeaconState
 	}
 
 	return &BeaconStateBellatrix{
-		GenesisTime:                  fmt.Sprintf("%d", st.GenesisTime()),
+		GenesisTime:                  fmt.Sprintf("%d", st.GenesisTime().Unix()),
 		GenesisValidatorsRoot:        hexutil.Encode(st.GenesisValidatorsRoot()),
 		Slot:                         fmt.Sprintf("%d", st.Slot()),
 		Fork:                         ForkFromConsensus(st.Fork()),
@@ -320,6 +323,10 @@ func BeaconStateBellatrixFromConsensus(st beaconState.BeaconState) (*BeaconState
 	}, nil
 }
 
+// ----------------------------------------------------------------------------
+// Capella
+// ----------------------------------------------------------------------------
+
 func BeaconStateCapellaFromConsensus(st beaconState.BeaconState) (*BeaconStateCapella, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -331,10 +338,7 @@ func BeaconStateCapellaFromConsensus(st beaconState.BeaconState) (*BeaconStateCa
 	for i, r := range srcSr {
 		sr[i] = hexutil.Encode(r)
 	}
-	srcHr, err := st.HistoricalRoots()
-	if err != nil {
-		return nil, err
-	}
+	srcHr := st.HistoricalRoots()
 	hr := make([]string, len(srcHr))
 	for i, r := range srcHr {
 		hr[i] = hexutil.Encode(r)
@@ -426,7 +430,7 @@ func BeaconStateCapellaFromConsensus(st beaconState.BeaconState) (*BeaconStateCa
 	}
 
 	return &BeaconStateCapella{
-		GenesisTime:                  fmt.Sprintf("%d", st.GenesisTime()),
+		GenesisTime:                  fmt.Sprintf("%d", st.GenesisTime().Unix()),
 		GenesisValidatorsRoot:        hexutil.Encode(st.GenesisValidatorsRoot()),
 		Slot:                         fmt.Sprintf("%d", st.Slot()),
 		Fork:                         ForkFromConsensus(st.Fork()),
@@ -457,6 +461,10 @@ func BeaconStateCapellaFromConsensus(st beaconState.BeaconState) (*BeaconStateCa
 	}, nil
 }
 
+// ----------------------------------------------------------------------------
+// Deneb
+// ----------------------------------------------------------------------------
+
 func BeaconStateDenebFromConsensus(st beaconState.BeaconState) (*BeaconStateDeneb, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -468,10 +476,7 @@ func BeaconStateDenebFromConsensus(st beaconState.BeaconState) (*BeaconStateDene
 	for i, r := range srcSr {
 		sr[i] = hexutil.Encode(r)
 	}
-	srcHr, err := st.HistoricalRoots()
-	if err != nil {
-		return nil, err
-	}
+	srcHr := st.HistoricalRoots()
 	hr := make([]string, len(srcHr))
 	for i, r := range srcHr {
 		hr[i] = hexutil.Encode(r)
@@ -563,7 +568,7 @@ func BeaconStateDenebFromConsensus(st beaconState.BeaconState) (*BeaconStateDene
 	}
 
 	return &BeaconStateDeneb{
-		GenesisTime:                  fmt.Sprintf("%d", st.GenesisTime()),
+		GenesisTime:                  fmt.Sprintf("%d", st.GenesisTime().Unix()),
 		GenesisValidatorsRoot:        hexutil.Encode(st.GenesisValidatorsRoot()),
 		Slot:                         fmt.Sprintf("%d", st.Slot()),
 		Fork:                         ForkFromConsensus(st.Fork()),
@@ -594,6 +599,10 @@ func BeaconStateDenebFromConsensus(st beaconState.BeaconState) (*BeaconStateDene
 	}, nil
 }
 
+// ----------------------------------------------------------------------------
+// Electra
+// ----------------------------------------------------------------------------
+
 func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateElectra, error) {
 	srcBr := st.BlockRoots()
 	br := make([]string, len(srcBr))
@@ -605,10 +614,7 @@ func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateEl
 	for i, r := range srcSr {
 		sr[i] = hexutil.Encode(r)
 	}
-	srcHr, err := st.HistoricalRoots()
-	if err != nil {
-		return nil, err
-	}
+	srcHr := st.HistoricalRoots()
 	hr := make([]string, len(srcHr))
 	for i, r := range srcHr {
 		hr[i] = hexutil.Encode(r)
@@ -674,7 +680,7 @@ func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateEl
 	if err != nil {
 		return nil, err
 	}
-	srcPayload, ok := execData.Proto().(*enginev1.ExecutionPayloadHeaderElectra)
+	srcPayload, ok := execData.Proto().(*enginev1.ExecutionPayloadHeaderDeneb)
 	if !ok {
 		return nil, errPayloadHeaderNotFound
 	}
@@ -722,7 +728,7 @@ func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateEl
 	if err != nil {
 		return nil, err
 	}
-	pbd, err := st.PendingBalanceDeposits()
+	pbd, err := st.PendingDeposits()
 	if err != nil {
 		return nil, err
 	}
@@ -736,7 +742,7 @@ func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateEl
 	}
 
 	return &BeaconStateElectra{
-		GenesisTime:                   fmt.Sprintf("%d", st.GenesisTime()),
+		GenesisTime:                   fmt.Sprintf("%d", st.GenesisTime().Unix()),
 		GenesisValidatorsRoot:         hexutil.Encode(st.GenesisValidatorsRoot()),
 		Slot:                          fmt.Sprintf("%d", st.Slot()),
 		Fork:                          ForkFromConsensus(st.Fork()),
@@ -770,8 +776,199 @@ func BeaconStateElectraFromConsensus(st beaconState.BeaconState) (*BeaconStateEl
 		EarliestExitEpoch:             fmt.Sprintf("%d", eee),
 		ConsolidationBalanceToConsume: fmt.Sprintf("%d", cbtc),
 		EarliestConsolidationEpoch:    fmt.Sprintf("%d", ece),
-		PendingBalanceDeposits:        PendingBalanceDepositsFromConsensus(pbd),
+		PendingDeposits:               PendingDepositsFromConsensus(pbd),
 		PendingPartialWithdrawals:     PendingPartialWithdrawalsFromConsensus(ppw),
 		PendingConsolidations:         PendingConsolidationsFromConsensus(pc),
 	}, nil
 }
+
+// ----------------------------------------------------------------------------
+// Fulu
+// ----------------------------------------------------------------------------
+
+func BeaconStateFuluFromConsensus(st beaconState.BeaconState) (*BeaconStateFulu, error) {
+	srcBr := st.BlockRoots()
+	br := make([]string, len(srcBr))
+	for i, r := range srcBr {
+		br[i] = hexutil.Encode(r)
+	}
+	srcSr := st.StateRoots()
+	sr := make([]string, len(srcSr))
+	for i, r := range srcSr {
+		sr[i] = hexutil.Encode(r)
+	}
+	srcHr := st.HistoricalRoots()
+	hr := make([]string, len(srcHr))
+	for i, r := range srcHr {
+		hr[i] = hexutil.Encode(r)
+	}
+	srcVotes := st.Eth1DataVotes()
+	votes := make([]*Eth1Data, len(srcVotes))
+	for i, e := range srcVotes {
+		votes[i] = Eth1DataFromConsensus(e)
+	}
+	srcVals := st.Validators()
+	vals := make([]*Validator, len(srcVals))
+	for i, v := range srcVals {
+		vals[i] = ValidatorFromConsensus(v)
+	}
+	srcBals := st.Balances()
+	bals := make([]string, len(srcBals))
+	for i, b := range srcBals {
+		bals[i] = fmt.Sprintf("%d", b)
+	}
+	srcRm := st.RandaoMixes()
+	rm := make([]string, len(srcRm))
+	for i, m := range srcRm {
+		rm[i] = hexutil.Encode(m)
+	}
+	srcSlashings := st.Slashings()
+	slashings := make([]string, len(srcSlashings))
+	for i, s := range srcSlashings {
+		slashings[i] = fmt.Sprintf("%d", s)
+	}
+	srcPrevPart, err := st.PreviousEpochParticipation()
+	if err != nil {
+		return nil, err
+	}
+	prevPart := make([]string, len(srcPrevPart))
+	for i, p := range srcPrevPart {
+		prevPart[i] = fmt.Sprintf("%d", p)
+	}
+	srcCurrPart, err := st.CurrentEpochParticipation()
+	if err != nil {
+		return nil, err
+	}
+	currPart := make([]string, len(srcCurrPart))
+	for i, p := range srcCurrPart {
+		currPart[i] = fmt.Sprintf("%d", p)
+	}
+	srcIs, err := st.InactivityScores()
+	if err != nil {
+		return nil, err
+	}
+	is := make([]string, len(srcIs))
+	for i, s := range srcIs {
+		is[i] = fmt.Sprintf("%d", s)
+	}
+	currSc, err := st.CurrentSyncCommittee()
+	if err != nil {
+		return nil, err
+	}
+	nextSc, err := st.NextSyncCommittee()
+	if err != nil {
+		return nil, err
+	}
+	execData, err := st.LatestExecutionPayloadHeader()
+	if err != nil {
+		return nil, err
+	}
+	srcPayload, ok := execData.Proto().(*enginev1.ExecutionPayloadHeaderDeneb)
+	if !ok {
+		return nil, errPayloadHeaderNotFound
+	}
+	payload, err := ExecutionPayloadHeaderElectraFromConsensus(srcPayload)
+	if err != nil {
+		return nil, err
+	}
+	srcHs, err := st.HistoricalSummaries()
+	if err != nil {
+		return nil, err
+	}
+	hs := make([]*HistoricalSummary, len(srcHs))
+	for i, s := range srcHs {
+		hs[i] = HistoricalSummaryFromConsensus(s)
+	}
+	nwi, err := st.NextWithdrawalIndex()
+	if err != nil {
+		return nil, err
+	}
+	nwvi, err := st.NextWithdrawalValidatorIndex()
+	if err != nil {
+		return nil, err
+	}
+	drsi, err := st.DepositRequestsStartIndex()
+	if err != nil {
+		return nil, err
+	}
+	dbtc, err := st.DepositBalanceToConsume()
+	if err != nil {
+		return nil, err
+	}
+	ebtc, err := st.ExitBalanceToConsume()
+	if err != nil {
+		return nil, err
+	}
+	eee, err := st.EarliestExitEpoch()
+	if err != nil {
+		return nil, err
+	}
+	cbtc, err := st.ConsolidationBalanceToConsume()
+	if err != nil {
+		return nil, err
+	}
+	ece, err := st.EarliestConsolidationEpoch()
+	if err != nil {
+		return nil, err
+	}
+	pbd, err := st.PendingDeposits()
+	if err != nil {
+		return nil, err
+	}
+	ppw, err := st.PendingPartialWithdrawals()
+	if err != nil {
+		return nil, err
+	}
+	pc, err := st.PendingConsolidations()
+	if err != nil {
+		return nil, err
+	}
+	srcLookahead, err := st.ProposerLookahead()
+	if err != nil {
+		return nil, err
+	}
+	lookahead := make([]string, len(srcLookahead))
+	for i, v := range srcLookahead {
+		lookahead[i] = fmt.Sprintf("%d", uint64(v))
+	}
+	return &BeaconStateFulu{
+		GenesisTime:                   fmt.Sprintf("%d", st.GenesisTime().Unix()),
+		GenesisValidatorsRoot:         hexutil.Encode(st.GenesisValidatorsRoot()),
+		Slot:                          fmt.Sprintf("%d", st.Slot()),
+		Fork:                          ForkFromConsensus(st.Fork()),
+		LatestBlockHeader:             BeaconBlockHeaderFromConsensus(st.LatestBlockHeader()),
+		BlockRoots:                    br,
+		StateRoots:                    sr,
+		HistoricalRoots:               hr,
+		Eth1Data:                      Eth1DataFromConsensus(st.Eth1Data()),
+		Eth1DataVotes:                 votes,
+		Eth1DepositIndex:              fmt.Sprintf("%d", st.Eth1DepositIndex()),
+		Validators:                    vals,
+		Balances:                      bals,
+		RandaoMixes:                   rm,
+		Slashings:                     slashings,
+		PreviousEpochParticipation:    prevPart,
+		CurrentEpochParticipation:     currPart,
+		JustificationBits:             hexutil.Encode(st.JustificationBits()),
+		PreviousJustifiedCheckpoint:   CheckpointFromConsensus(st.PreviousJustifiedCheckpoint()),
+		CurrentJustifiedCheckpoint:    CheckpointFromConsensus(st.CurrentJustifiedCheckpoint()),
+		FinalizedCheckpoint:           CheckpointFromConsensus(st.FinalizedCheckpoint()),
+		InactivityScores:              is,
+		CurrentSyncCommittee:          SyncCommitteeFromConsensus(currSc),
+		NextSyncCommittee:             SyncCommitteeFromConsensus(nextSc),
+		LatestExecutionPayloadHeader:  payload,
+		NextWithdrawalIndex:           fmt.Sprintf("%d", nwi),
+		NextWithdrawalValidatorIndex:  fmt.Sprintf("%d", nwvi),
+		HistoricalSummaries:           hs,
+		DepositRequestsStartIndex:     fmt.Sprintf("%d", drsi),
+		DepositBalanceToConsume:       fmt.Sprintf("%d", dbtc),
+		ExitBalanceToConsume:          fmt.Sprintf("%d", ebtc),
+		EarliestExitEpoch:             fmt.Sprintf("%d", eee),
+		ConsolidationBalanceToConsume: fmt.Sprintf("%d", cbtc),
+		EarliestConsolidationEpoch:    fmt.Sprintf("%d", ece),
+		PendingDeposits:               PendingDepositsFromConsensus(pbd),
+		PendingPartialWithdrawals:     PendingPartialWithdrawalsFromConsensus(ppw),
+		PendingConsolidations:         PendingConsolidationsFromConsensus(pc),
+		ProposerLookahead:             lookahead,
+	}, nil
+}

api/server/structs/conversions_test.go

@@ -3,8 +3,10 @@ package structs
 import (
 	"testing"
 
-	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	eth "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 )
 
 func TestDepositSnapshotFromConsensus(t *testing.T) {
@@ -24,3 +26,350 @@ func TestDepositSnapshotFromConsensus(t *testing.T) {
 	require.Equal(t, "0x1234", res.ExecutionBlockHash)
 	require.Equal(t, "67890", res.ExecutionBlockHeight)
 }
+
+func TestSignedBLSToExecutionChange_ToConsensus(t *testing.T) {
+	s := &SignedBLSToExecutionChange{Message: nil, Signature: ""}
+	_, err := s.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestSignedValidatorRegistration_ToConsensus(t *testing.T) {
+	s := &SignedValidatorRegistration{Message: nil, Signature: ""}
+	_, err := s.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestSignedContributionAndProof_ToConsensus(t *testing.T) {
+	s := &SignedContributionAndProof{Message: nil, Signature: ""}
+	_, err := s.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestContributionAndProof_ToConsensus(t *testing.T) {
+	c := &ContributionAndProof{
+		Contribution:    nil,
+		AggregatorIndex: "invalid",
+		SelectionProof:  "",
+	}
+	_, err := c.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestSignedAggregateAttestationAndProof_ToConsensus(t *testing.T) {
+	s := &SignedAggregateAttestationAndProof{Message: nil, Signature: ""}
+	_, err := s.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestAggregateAttestationAndProof_ToConsensus(t *testing.T) {
+	a := &AggregateAttestationAndProof{
+		AggregatorIndex: "1",
+		Aggregate:       nil,
+		SelectionProof:  "",
+	}
+	_, err := a.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestAttestation_ToConsensus(t *testing.T) {
+	a := &Attestation{
+		AggregationBits: "0x10",
+		Data:            nil,
+		Signature:       "",
+	}
+	_, err := a.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestSingleAttestation_ToConsensus(t *testing.T) {
+	s := &SingleAttestation{
+		CommitteeIndex: "1",
+		AttesterIndex:  "1",
+		Data:           nil,
+		Signature:      "",
+	}
+	_, err := s.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestSignedVoluntaryExit_ToConsensus(t *testing.T) {
+	s := &SignedVoluntaryExit{Message: nil, Signature: ""}
+	_, err := s.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestProposerSlashing_ToConsensus(t *testing.T) {
+	p := &ProposerSlashing{SignedHeader1: nil, SignedHeader2: nil}
+	_, err := p.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestProposerSlashing_FromConsensus(t *testing.T) {
+	input := []*eth.ProposerSlashing{
+		{
+			Header_1: &eth.SignedBeaconBlockHeader{
+				Header: &eth.BeaconBlockHeader{
+					Slot:          1,
+					ProposerIndex: 2,
+					ParentRoot:    []byte{3},
+					StateRoot:     []byte{4},
+					BodyRoot:      []byte{5},
+				},
+				Signature: []byte{6},
+			},
+			Header_2: &eth.SignedBeaconBlockHeader{
+				Header: &eth.BeaconBlockHeader{
+					Slot:          7,
+					ProposerIndex: 8,
+					ParentRoot:    []byte{9},
+					StateRoot:     []byte{10},
+					BodyRoot:      []byte{11},
+				},
+				Signature: []byte{12},
+			},
+		},
+		{
+			Header_1: &eth.SignedBeaconBlockHeader{
+				Header: &eth.BeaconBlockHeader{
+					Slot:          13,
+					ProposerIndex: 14,
+					ParentRoot:    []byte{15},
+					StateRoot:     []byte{16},
+					BodyRoot:      []byte{17},
+				},
+				Signature: []byte{18},
+			},
+			Header_2: &eth.SignedBeaconBlockHeader{
+				Header: &eth.BeaconBlockHeader{
+					Slot:          19,
+					ProposerIndex: 20,
+					ParentRoot:    []byte{21},
+					StateRoot:     []byte{22},
+					BodyRoot:      []byte{23},
+				},
+				Signature: []byte{24},
+			},
+		},
+	}
+
+	expectedResult := []*ProposerSlashing{
+		{
+			SignedHeader1: &SignedBeaconBlockHeader{
+				Message: &BeaconBlockHeader{
+					Slot:          "1",
+					ProposerIndex: "2",
+					ParentRoot:    hexutil.Encode([]byte{3}),
+					StateRoot:     hexutil.Encode([]byte{4}),
+					BodyRoot:      hexutil.Encode([]byte{5}),
+				},
+				Signature: hexutil.Encode([]byte{6}),
+			},
+			SignedHeader2: &SignedBeaconBlockHeader{
+				Message: &BeaconBlockHeader{
+					Slot:          "7",
+					ProposerIndex: "8",
+					ParentRoot:    hexutil.Encode([]byte{9}),
+					StateRoot:     hexutil.Encode([]byte{10}),
+					BodyRoot:      hexutil.Encode([]byte{11}),
+				},
+				Signature: hexutil.Encode([]byte{12}),
+			},
+		},
+		{
+			SignedHeader1: &SignedBeaconBlockHeader{
+				Message: &BeaconBlockHeader{
+					Slot:          "13",
+					ProposerIndex: "14",
+					ParentRoot:    hexutil.Encode([]byte{15}),
+					StateRoot:     hexutil.Encode([]byte{16}),
+					BodyRoot:      hexutil.Encode([]byte{17}),
+				},
+				Signature: hexutil.Encode([]byte{18}),
+			},
+			SignedHeader2: &SignedBeaconBlockHeader{
+				Message: &BeaconBlockHeader{
+					Slot:          "19",
+					ProposerIndex: "20",
+					ParentRoot:    hexutil.Encode([]byte{21}),
+					StateRoot:     hexutil.Encode([]byte{22}),
+					BodyRoot:      hexutil.Encode([]byte{23}),
+				},
+				Signature: hexutil.Encode([]byte{24}),
+			},
+		},
+	}
+
+	result := ProposerSlashingsFromConsensus(input)
+	assert.DeepEqual(t, expectedResult, result)
+}
+
+func TestAttesterSlashing_ToConsensus(t *testing.T) {
+	a := &AttesterSlashing{Attestation1: nil, Attestation2: nil}
+	_, err := a.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}
+
+func TestAttesterSlashing_FromConsensus(t *testing.T) {
+	input := []*eth.AttesterSlashing{
+		{
+			Attestation_1: &eth.IndexedAttestation{
+				AttestingIndices: []uint64{1, 2},
+				Data: &eth.AttestationData{
+					Slot:            3,
+					CommitteeIndex:  4,
+					BeaconBlockRoot: []byte{5},
+					Source: &eth.Checkpoint{
+						Epoch: 6,
+						Root:  []byte{7},
+					},
+					Target: &eth.Checkpoint{
+						Epoch: 8,
+						Root:  []byte{9},
+					},
+				},
+				Signature: []byte{10},
+			},
+			Attestation_2: &eth.IndexedAttestation{
+				AttestingIndices: []uint64{11, 12},
+				Data: &eth.AttestationData{
+					Slot:            13,
+					CommitteeIndex:  14,
+					BeaconBlockRoot: []byte{15},
+					Source: &eth.Checkpoint{
+						Epoch: 16,
+						Root:  []byte{17},
+					},
+					Target: &eth.Checkpoint{
+						Epoch: 18,
+						Root:  []byte{19},
+					},
+				},
+				Signature: []byte{20},
+			},
+		},
+		{
+			Attestation_1: &eth.IndexedAttestation{
+				AttestingIndices: []uint64{21, 22},
+				Data: &eth.AttestationData{
+					Slot:            23,
+					CommitteeIndex:  24,
+					BeaconBlockRoot: []byte{25},
+					Source: &eth.Checkpoint{
+						Epoch: 26,
+						Root:  []byte{27},
+					},
+					Target: &eth.Checkpoint{
+						Epoch: 28,
+						Root:  []byte{29},
+					},
+				},
+				Signature: []byte{30},
+			},
+			Attestation_2: &eth.IndexedAttestation{
+				AttestingIndices: []uint64{31, 32},
+				Data: &eth.AttestationData{
+					Slot:            33,
+					CommitteeIndex:  34,
+					BeaconBlockRoot: []byte{35},
+					Source: &eth.Checkpoint{
+						Epoch: 36,
+						Root:  []byte{37},
+					},
+					Target: &eth.Checkpoint{
+						Epoch: 38,
+						Root:  []byte{39},
+					},
+				},
+				Signature: []byte{40},
+			},
+		},
+	}
+
+	expectedResult := []*AttesterSlashing{
+		{
+			Attestation1: &IndexedAttestation{
+				AttestingIndices: []string{"1", "2"},
+				Data: &AttestationData{
+					Slot:            "3",
+					CommitteeIndex:  "4",
+					BeaconBlockRoot: hexutil.Encode([]byte{5}),
+					Source: &Checkpoint{
+						Epoch: "6",
+						Root:  hexutil.Encode([]byte{7}),
+					},
+					Target: &Checkpoint{
+						Epoch: "8",
+						Root:  hexutil.Encode([]byte{9}),
+					},
+				},
+				Signature: hexutil.Encode([]byte{10}),
+			},
+			Attestation2: &IndexedAttestation{
+				AttestingIndices: []string{"11", "12"},
+				Data: &AttestationData{
+					Slot:            "13",
+					CommitteeIndex:  "14",
+					BeaconBlockRoot: hexutil.Encode([]byte{15}),
+					Source: &Checkpoint{
+						Epoch: "16",
+						Root:  hexutil.Encode([]byte{17}),
+					},
+					Target: &Checkpoint{
+						Epoch: "18",
+						Root:  hexutil.Encode([]byte{19}),
+					},
+				},
+				Signature: hexutil.Encode([]byte{20}),
+			},
+		},
+		{
+			Attestation1: &IndexedAttestation{
+				AttestingIndices: []string{"21", "22"},
+				Data: &AttestationData{
+					Slot:            "23",
+					CommitteeIndex:  "24",
+					BeaconBlockRoot: hexutil.Encode([]byte{25}),
+					Source: &Checkpoint{
+						Epoch: "26",
+						Root:  hexutil.Encode([]byte{27}),
+					},
+					Target: &Checkpoint{
+						Epoch: "28",
+						Root:  hexutil.Encode([]byte{29}),
+					},
+				},
+				Signature: hexutil.Encode([]byte{30}),
+			},
+			Attestation2: &IndexedAttestation{
+				AttestingIndices: []string{"31", "32"},
+				Data: &AttestationData{
+					Slot:            "33",
+					CommitteeIndex:  "34",
+					BeaconBlockRoot: hexutil.Encode([]byte{35}),
+					Source: &Checkpoint{
+						Epoch: "36",
+						Root:  hexutil.Encode([]byte{37}),
+					},
+					Target: &Checkpoint{
+						Epoch: "38",
+						Root:  hexutil.Encode([]byte{39}),
+					},
+				},
+				Signature: hexutil.Encode([]byte{40}),
+			},
+		},
+	}
+
+	result := AttesterSlashingsFromConsensus(input)
+	assert.DeepEqual(t, expectedResult, result)
+}
+
+func TestIndexedAttestation_ToConsensus(t *testing.T) {
+	a := &IndexedAttestation{
+		AttestingIndices: []string{"1"},
+		Data:             nil,
+		Signature:        "invalid",
+	}
+	_, err := a.ToConsensus()
+	require.ErrorContains(t, errNilValue.Error(), err)
+}

api/server/structs/endpoints_beacon.go

@@ -21,11 +21,12 @@ type GetCommitteesResponse struct {
 }
 
 type ListAttestationsResponse struct {
-	Data []*Attestation `json:"data"`
+	Version string          `json:"version,omitempty"`
+	Data    json.RawMessage `json:"data"`
 }
 
 type SubmitAttestationsRequest struct {
-	Data []*Attestation `json:"data"`
+	Data json.RawMessage `json:"data"`
 }
 
 type ListVoluntaryExitsResponse struct {
@@ -77,8 +78,8 @@ type GetBlockHeaderResponse struct {
 }
 
 type GetValidatorsRequest struct {
-	Ids      []string `json:"ids"`
-	Statuses []string `json:"statuses"`
+	Ids      []string `json:"ids,omitempty"`
+	Statuses []string `json:"statuses,omitempty"`
 }
 
 type GetValidatorsResponse struct {
@@ -99,6 +100,12 @@ type GetValidatorBalancesResponse struct {
 	Data                []*ValidatorBalance `json:"data"`
 }
 
+type GetValidatorIdentitiesResponse struct {
+	ExecutionOptimistic bool                 `json:"execution_optimistic"`
+	Finalized           bool                 `json:"finalized"`
+	Data                []*ValidatorIdentity `json:"data"`
+}
+
 type ValidatorContainer struct {
 	Index     string     `json:"index"`
 	Balance   string     `json:"balance"`
@@ -111,6 +118,12 @@ type ValidatorBalance struct {
 	Balance string `json:"balance"`
 }
 
+type ValidatorIdentity struct {
+	Index           string `json:"index"`
+	Pubkey          string `json:"pubkey"`
+	ActivationEpoch string `json:"activation_epoch"`
+}
+
 type GetBlockResponse struct {
 	Data *SignedBlock `json:"data"`
 }
@@ -133,6 +146,13 @@ type GetBlockAttestationsResponse struct {
 	Data                []*Attestation `json:"data"`
 }
 
+type GetBlockAttestationsV2Response struct {
+	Version             string          `json:"version"`
+	ExecutionOptimistic bool            `json:"execution_optimistic"`
+	Finalized           bool            `json:"finalized"`
+	Data                json.RawMessage `json:"data"` // Accepts both `Attestation` and `AttestationElectra` types
+}
+
 type GetStateRootResponse struct {
 	ExecutionOptimistic bool       `json:"execution_optimistic"`
 	Finalized           bool       `json:"finalized"`
@@ -169,7 +189,8 @@ type BLSToExecutionChangesPoolResponse struct {
 }
 
 type GetAttesterSlashingsResponse struct {
-	Data []*AttesterSlashing `json:"data"`
+	Version string          `json:"version,omitempty"`
+	Data    json.RawMessage `json:"data"` // Accepts both `[]*AttesterSlashing` and `[]*AttesterSlashingElectra` types
 }
 
 type GetProposerSlashingsResponse struct {
@@ -241,3 +262,31 @@ type ChainHead struct {
 	PreviousJustifiedBlockRoot string `json:"previous_justified_block_root"`
 	OptimisticStatus           bool   `json:"optimistic_status"`
 }
+
+type GetPendingConsolidationsResponse struct {
+	Version             string                  `json:"version"`
+	ExecutionOptimistic bool                    `json:"execution_optimistic"`
+	Finalized           bool                    `json:"finalized"`
+	Data                []*PendingConsolidation `json:"data"`
+}
+
+type GetPendingDepositsResponse struct {
+	Version             string            `json:"version"`
+	ExecutionOptimistic bool              `json:"execution_optimistic"`
+	Finalized           bool              `json:"finalized"`
+	Data                []*PendingDeposit `json:"data"`
+}
+
+type GetPendingPartialWithdrawalsResponse struct {
+	Version             string                      `json:"version"`
+	ExecutionOptimistic bool                        `json:"execution_optimistic"`
+	Finalized           bool                        `json:"finalized"`
+	Data                []*PendingPartialWithdrawal `json:"data"`
+}
+
+type GetProposerLookaheadResponse struct {
+	Version             string   `json:"version"`
+	ExecutionOptimistic bool     `json:"execution_optimistic"`
+	Finalized           bool     `json:"finalized"`
+	Data                []string `json:"data"` // validator indexes
+}

api/server/structs/endpoints_blob.go

@@ -1,7 +1,10 @@
 package structs
 
 type SidecarsResponse struct {
-	Data []*Sidecar `json:"data"`
+	Version             string     `json:"version"`
+	Data                []*Sidecar `json:"data"`
+	ExecutionOptimistic bool       `json:"execution_optimistic"`
+	Finalized           bool       `json:"finalized"`
 }
 
 type Sidecar struct {
@@ -12,3 +15,12 @@ type Sidecar struct {
 	KzgProof                 string                   `json:"kzg_proof"`
 	CommitmentInclusionProof []string                 `json:"kzg_commitment_inclusion_proof"`
 }
+
+type BlobSidecars struct {
+	Sidecars []*Sidecar `json:"sidecars"`
+}
+
+type PublishBlobsRequest struct {
+	BlobSidecars *BlobSidecars `json:"blob_sidecars"`
+	BlockRoot    string        `json:"block_root"`
+}

api/server/structs/endpoints_debug.go

@@ -54,4 +54,5 @@ type ForkChoiceNodeExtraData struct {
 	Balance                  string `json:"balance"`
 	ExecutionOptimistic      bool   `json:"execution_optimistic"`
 	TimeStamp                string `json:"timestamp"`
+	Target                   string `json:"target"`
 }

api/server/structs/endpoints_events.go

@@ -20,6 +20,18 @@ type BlockEvent struct {
 	ExecutionOptimistic bool   `json:"execution_optimistic"`
 }
 
+type BlockGossipEvent struct {
+	Slot  string `json:"slot"`
+	Block string `json:"block"`
+}
+
+type DataColumnGossipEvent struct {
+	Slot           string   `json:"slot"`
+	Index          string   `json:"index"`
+	BlockRoot      string   `json:"block_root"`
+	KzgCommitments []string `json:"kzg_commitments"`
+}
+
 type AggregatedAttEventSource struct {
 	Aggregate *Attestation `json:"aggregate"`
 }
@@ -96,21 +108,7 @@ type LightClientFinalityUpdateEvent struct {
 	Data    *LightClientFinalityUpdate `json:"data"`
 }
 
-type LightClientFinalityUpdate struct {
-	AttestedHeader  *BeaconBlockHeader `json:"attested_header"`
-	FinalizedHeader *BeaconBlockHeader `json:"finalized_header"`
-	FinalityBranch  []string           `json:"finality_branch"`
-	SyncAggregate   *SyncAggregate     `json:"sync_aggregate"`
-	SignatureSlot   string             `json:"signature_slot"`
-}
-
 type LightClientOptimisticUpdateEvent struct {
 	Version string                       `json:"version"`
 	Data    *LightClientOptimisticUpdate `json:"data"`
 }
-
-type LightClientOptimisticUpdate struct {
-	AttestedHeader *BeaconBlockHeader `json:"attested_header"`
-	SyncAggregate  *SyncAggregate     `json:"sync_aggregate"`
-	SignatureSlot  string             `json:"signature_slot"`
-}

api/server/structs/endpoints_lightclient.go

@@ -1,31 +1,73 @@
 package structs
 
+import "encoding/json"
+
+type LightClientHeader struct {
+	Beacon *BeaconBlockHeader `json:"beacon"`
+}
+
+type LightClientHeaderCapella struct {
+	Beacon          *BeaconBlockHeader             `json:"beacon"`
+	Execution       *ExecutionPayloadHeaderCapella `json:"execution"`
+	ExecutionBranch []string                       `json:"execution_branch"`
+}
+
+type LightClientHeaderDeneb struct {
+	Beacon          *BeaconBlockHeader           `json:"beacon"`
+	Execution       *ExecutionPayloadHeaderDeneb `json:"execution"`
+	ExecutionBranch []string                     `json:"execution_branch"`
+}
+
+type LightClientBootstrap struct {
+	Header                     json.RawMessage `json:"header"`
+	CurrentSyncCommittee       *SyncCommittee  `json:"current_sync_committee"`
+	CurrentSyncCommitteeBranch []string        `json:"current_sync_committee_branch"`
+}
+
+type LightClientUpdate struct {
+	AttestedHeader          json.RawMessage `json:"attested_header"`
+	NextSyncCommittee       *SyncCommittee  `json:"next_sync_committee,omitempty"`
+	FinalizedHeader         json.RawMessage `json:"finalized_header,omitempty"`
+	SyncAggregate           *SyncAggregate  `json:"sync_aggregate"`
+	NextSyncCommitteeBranch []string        `json:"next_sync_committee_branch,omitempty"`
+	FinalityBranch          []string        `json:"finality_branch,omitempty"`
+	SignatureSlot           string          `json:"signature_slot"`
+}
+
+type LightClientFinalityUpdate struct {
+	AttestedHeader  json.RawMessage `json:"attested_header"`
+	FinalizedHeader json.RawMessage `json:"finalized_header"`
+	FinalityBranch  []string        `json:"finality_branch"`
+	SyncAggregate   *SyncAggregate  `json:"sync_aggregate"`
+	SignatureSlot   string          `json:"signature_slot"`
+}
+
+type LightClientOptimisticUpdate struct {
+	AttestedHeader json.RawMessage `json:"attested_header"`
+	SyncAggregate  *SyncAggregate  `json:"sync_aggregate"`
+	SignatureSlot  string          `json:"signature_slot"`
+}
+
 type LightClientBootstrapResponse struct {
 	Version string                `json:"version"`
 	Data    *LightClientBootstrap `json:"data"`
 }
 
-type LightClientBootstrap struct {
-	Header                     *BeaconBlockHeader `json:"header"`
-	CurrentSyncCommittee       *SyncCommittee     `json:"current_sync_committee"`
-	CurrentSyncCommitteeBranch []string           `json:"current_sync_committee_branch"`
-}
-
-type LightClientUpdate struct {
-	AttestedHeader          *BeaconBlockHeader `json:"attested_header"`
-	NextSyncCommittee       *SyncCommittee     `json:"next_sync_committee,omitempty"`
-	FinalizedHeader         *BeaconBlockHeader `json:"finalized_header,omitempty"`
-	SyncAggregate           *SyncAggregate     `json:"sync_aggregate"`
-	NextSyncCommitteeBranch []string           `json:"next_sync_committee_branch,omitempty"`
-	FinalityBranch          []string           `json:"finality_branch,omitempty"`
-	SignatureSlot           string             `json:"signature_slot"`
-}
-
-type LightClientUpdateWithVersion struct {
+type LightClientUpdateResponse struct {
 	Version string             `json:"version"`
 	Data    *LightClientUpdate `json:"data"`
 }
 
-type LightClientUpdatesByRangeResponse struct {
-	Updates []*LightClientUpdateWithVersion `json:"updates"`
+type LightClientFinalityUpdateResponse struct {
+	Version string                     `json:"version"`
+	Data    *LightClientFinalityUpdate `json:"data"`
+}
+
+type LightClientOptimisticUpdateResponse struct {
+	Version string                       `json:"version"`
+	Data    *LightClientOptimisticUpdate `json:"data"`
+}
+
+type LightClientUpdatesByRangeResponse struct {
+	Updates []*LightClientUpdateResponse `json:"updates"`
 }

api/server/structs/endpoints_node.go

@@ -27,14 +27,22 @@ type Identity struct {
 type Metadata struct {
 	SeqNumber string `json:"seq_number"`
 	Attnets   string `json:"attnets"`
+	Syncnets  string `json:"syncnets,omitempty"`
+	Cgc       string `json:"custody_group_count,omitempty"`
 }
 
 type GetPeerResponse struct {
 	Data *Peer `json:"data"`
 }
 
+// Added Meta to align with beacon-api: https://ethereum.github.io/beacon-APIs/#/Node/getPeers
+type Meta struct {
+	Count int `json:"count"`
+}
+
 type GetPeersResponse struct {
 	Data []*Peer `json:"data"`
+	Meta Meta    `json:"meta"`
 }
 
 type Peer struct {