Event data use cached proposer index

* comment updates and changelog

* some missed comments

.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/workflows/changelog.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout source code
-        uses: actions/checkout@v3
+        uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0
 
       - name: Download unclog binary
         uses: dsaltares/fetch-gh-release-asset@aa2ab1243d6e0d5b405b973c89fa4d06a2d0fff7 # 1.1.2
@@ -23,7 +23,7 @@ jobs:
 
       - name: Get new changelog files
         id: new-changelog-files
-        uses: tj-actions/changed-files@v45
+        uses: OffchainLabs/gh-action-changed-files@9200e69727eb73eb060652b19946b8a2fdfb654b # v4.0.8
         with:
           files: |
             changelog/**.md

.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
@@ -197,6 +197,7 @@ nogo(
         "//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",

CHANGELOG.md

@@ -4,6 +4,197 @@ All notable changes to this project will be documented in this file.
 
 The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.
 
+## [v6.0.0](https://github.com/prysmaticlabs/prysm/compare/v5.3.2...v6.0.0) - 2025-04-21
+
+This release introduces Mainnet support for the upcoming Electra + Prague (Pectra) fork. The fork is scheduled for mainnet epoch 364032 (May 7, 2025, 10:05:11 UTC). You MUST update Prysm Beacon Node, Prysm Validator Client, and your execution layer client to the Pectra ready release prior to the fork to stay on the correct chain.
+
+Besides Pectra, we have more light client API support, cleanups, and a few bugfixes. Please review the changelog below and update your client as soon as practical before May 7.
+
+This release is **mandatory** for all operators before May 7.
+
+### Added
+
+- Implemented validator identities Beacon API endpoint. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15086)
+- Add SSZ support to light client updates by range API. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15082)
+- Add light client ssz types to the spec test. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15097)
+- Added the ability for execution requests to be tested in e2e with electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14971)
+- Add warning messages for gas limit ranges that might be problematic. Low gas limits (≤10% of default) may cause transactions to fail, while high gas limits (>150% of default) could lead to block propagation issues. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15078)
+- Add light client store object to the beacon node object. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15120)
+- prysmctl option in wrapper script to generate devnet ssz. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15145)
+- Add support for Electra fork epoch. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15132)
+
+### Changed
+
+- The validator client will no longer use the full list of committee values but instead use the committee length and validator committee index. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15039)
+- Remove the header `Content-Disposition` from the `httputil.WriteSSZ` function. No `filename` parameter is needed anymore. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15092)
+- Sort attestations in proposer block by reward. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15093)
+- More efficient query method for stategen to retrieve blocks between a given state and the replay target block. This avoids attempting to look up blocks that are not needed for head replay queries, which may be missing due to a previous rollback bug. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15063)
+- removed old web3signer metrics in favor for a universal one. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14920)
+- Deprecated everything related with the gRPC API. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14944)
+- Migrate Prysm repo to Offchain Labs organization ahead of Pectra upgrade v6. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15140)
+
+### Deprecated
+
+- deprecates and removes usage of the `--trace` flag and`--cpuprofile` flag in favor of just using `--pprof`. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15083)
+
+### Removed
+
+- Remove /eth/v1/beacon/states/head/committees call when getting duties. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15039)
+- Removed unused hack scripts. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15157)
+- Remove `disable-committee-aware-packing` flag. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15162)
+- Remove deprecated flags for the major release. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15165)
+- Removed Beacon API endpoints which have been deprecated at the Deneb fork. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15166)
+
+### Fixed
+
+- The `--rpc` flag will now properly enable the keymanager APIs without web. The `--web` will enable both validator api endpoints and web. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15080)
+- Use latest state to pack attestation. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15113)
+- Clean up dangling block index entries for blocks that were previously deleted by incomplete cleanup code. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15040)
+- Fixed to use io stream instead of stream read. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15089)
+- When using a DV, send all aggregations for a slot and committee. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15110)
+- Fixed a bug in consolidation request processing. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15122)
+- Fix State Getter for pending withdrawal balance. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15123)
+- Fixed a bug in checking for attestation lengths in our block. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15134)
+- Fix Committee Index Check For Aggregates. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15146)
+- Fix filtering by committee index post-Electra in `ListAttestationsV2`. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15148)
+- Peers giving invalid data in range syncing are now downscored. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15149)
+- Adding fork guard to attestation api endpoints so that it doesn't accidentally include wrong attestation types in the pool. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15161)
+- fixed underflow with balances in leaking edge case with expected withdrawals. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15191)
+- Attribute block and blob issues to correct peers during range syncing. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15173)
+
+## [v5.3.2](https://github.com/prysmaticlabs/prysm/compare/v5.3.1...v5.3.2) - 2025-03-25
+
+This release introduces support for the `Hoodi` testnet.
+
+Release highlights:
+
+- Ability to run the node on the `Hoodi` tesnet. See https://blog.ethereum.org/2025/03/18/hoodi-holesky for more information about `Hoodi`.
+- A new feature that allows treat certain blocks as invalid. This is especially useful when the network is split, allowing the node to discontinue following unwanted forks.
+
+Testnet operators are required to update to this release. Without this release you will be unable to run the node on the `Hoodi` testnet.
+
+Mainnet operators are recommended to update to this release at their regular cadence.
+
+### Added
+
+- enable SSZ for builder API calls. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14976)
+- Add Hoodi testnet flag `--hoodi` to specify Hoodi testnet config and bootnodes. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15057)
+- block_gossip topic support to the beacon api event stream. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15038)
+- Added a static analyzer to discourage use of panic() in Prysm. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15075)
+- Add a feature flag `--blacklist-roots` to allow the node to specify blocks that will be treated as invalid. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15030)
+
+### Changed
+
+- changed request object for `POST /eth/v1/beacon/states/head/validators` to omit the field if empty for satisfying other clients. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15031)
+- Update spec test to v1.5.0-beta.3. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15050)
+- Update Gossip and RPC message limits to comply with the spec. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14799)
+- Return 404 instead of 500 from API when when a blob for a requested index is not found. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14845)
+- Save Electra orphaned attestations into attestations pool's block attestations. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15060)
+- Removed redundant string conversion in `BeaconDbStater.State` to improve code clarity and maintainability. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15081)
+
+### Fixed
+
+- Update seen unaggregated att cache to properly handle Electra attestations. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15034)
+- cosmetic fix for calling `/prysm/validators/performance` when connecting to non prysm beacon nodes and removing the 404 error log. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15062)
+- Tracked validator cache: Make sure no to loose the reference. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15077)
+- Fixed proposing at genesis when starting post Bellatrix. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15084)
+
+## [v5.3.1](https://github.com/prysmaticlabs/prysm/compare/v5.3.0...v5.3.1) - 2025-03-13
+
+This release is packed with critical fixes for **Electra** and some important fixes for mainnet too. 
+
+The release highlights include:
+
+- Ensure that deleting a block from the database clears its entry in the slot->root db index. This issue was causing some operators to have a bricked database, requiring a full resync. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15011)
+- Updated go to go1.24.0. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14969)
+- Added a feature flag to sync from an arbitrary beacon block root at startup. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15000)
+- Updated default gas limit from 30M to 36M. Override this with `--suggested-gas-limit=` in the validator client. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14858)
+
+Known issues in **Electra**:
+
+- Duplicate attestations are needlessly processed. This is being addressed in [[PR]](https://github.com/prysmaticlabs/prysm/pull/15034).
+
+Testnet operators are strongly encouraged to update to this release. There are many fixes and improvements from the Holesky upgrade incident.
+
+Mainnet operators are recommended to update to this release at their regular cadence. 
+
+### Added
+
+- enable E2E for minimal and mainnet tests. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14842)
+- enable web3signer E2E for electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14936)
+- Enable multiclient E2E for electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14946)
+- Enable Scenario E2E tests with electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14946)
+- Add endpoint for getting pending deposits. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14941)
+- Add request hash to header for builder: executable data to block. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14955)
+- Log execution requests in each block. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14956)
+- Add endpoint for getting pending partial withdrawals. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14949)
+- Tracked validators cache: Added the `ItemCount` method. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14957)
+- Tracked validators cache: Added the `Indices` method. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14957)
+- Added deposit request testing for electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14964)
+- Added support for otel tracing transport in HTTP clients in Prysm. This allows for tracing headers to be sent with http requests such that spans between the validator and beacon chain can be connected in the tracing graph. This change does nothing without `--enable-tracing`. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14972)
+- Add SSZ support to light client finality and optimistic APIs. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14836)
+- add log to committee index when committeebits are not the expected length of 1. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14993)
+- Add acceptable address types for static peers. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14886)
+- Added a feature flag to sync from an arbitrary beacon block root at startup. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15000)
+
+### Changed
+
+- updates geth to 1.15.0. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14842)
+- Updates blst to v3.14.0 and fixes the references in our deps.bzl file. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14921)
+- Updated tracing exporter from jaeger to otelhttp. This should not be a breaking change. Jaeger supports otel format, however you may need to update your URL as the default otel-collector port is 4318. See the [OpenTelemtry Protocol Exporter docs](https://opentelemetry.io/docs/specs/otel/protocol/exporter/) for more details. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14928)
+- Don't use MaxCover for Electra on-chain attestations. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14925)
+- Tracked validators cache: Remove validators from the cache if not seen after 1 hour. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14957)
+- execution requests errors on ssz length have been improved. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14962)
+- deprecate beacon api endpoints based on [3.0.0 release](https://github.com/ethereum/beacon-APIs/pull/506) for electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14967)
+- Use go-cmp for printing better diffs for assertions.DeepEqual. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14978)
+- Reorganized beacon chain flags in `--help` text into logical sections. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14959)
+- `--validators-registration-batch-size`: Change default value from `0` to `200`. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14981)
+- Updated go to go1.24.0. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14969)
+- Updated gosec to v2.22.1 and golangci to v1.64.5. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14969)
+- Updated github.com/trailofbits/go-mutexasserts. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14969)
+- Updated rules_go to cf3c3af34bd869b864f5f2b98e2f41c2b220d6c9 to support go1.24.0. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14969)
+- Validate blob sidecar re-order signature and bad parent block. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15013)
+- Updated default gas limit from 30M to 36M. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14858)
+- Ignore errors from `hasSeenBit` and don't pack unaggregated attestations. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15018)
+
+### Removed
+
+- Remove Fulu state and block. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14905)
+- Removed the log summarizing all started services. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14958)
+
+### Fixed
+
+- fixed max and target blob per block from static to dynamic values. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14911)
+- refactored publish block and block ssz functions to fix gocognit. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14913)
+- refactored publish blinded block and blinded block ssz to correctly deal with version headers and sent blocks. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14913)
+- Only check for electra related engine methods if electra is active. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14924)
+- Fixed bug that breaks new blob storage layout code on Windows, caused by accidental use of platform-dependent path parsing package. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14931)
+- Fix E2E Process Deposit Evaluator for Electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14933)
+- Fixed the `bazel run //:gazelle` command in `DEPENDENCIES.md`. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14934)
+- Fix E2E Deposit Activation Evaluator for Electra. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14938)
+- Dedicated processing of `SingleAttestation` in the monitor service. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14965)
+- adding in content type and accept headers for builder API call on registration. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14961)
+- fixed gocognit in block conversions between json and proto types. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14953)
+- Lint: Fix violations of S1009: should omit nil check; len() for nil slices is defined as zero. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14973)
+- Lint: Fix violations of non-constant format string in call. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14974)
+- Fixed violations of gosec G301. This is a check that created files and directories have file permissions 0750 and 0600 respectively. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14980)
+- Check for the correct attester slashing type during gossip validation. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14985)
+- cosmetic fix for post electra validator logs displaying attestation committee information correctly. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14992)
+- fix inserting the wrong committee index into the seen cache for electra attestations. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14998)
+- Allow any block type to be unmarshaled rather than only phase0 blocks in `slotByBlockRoot`. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15008)
+- Fixed pruner to not block while pruning large database by introducing batchSize. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14929)
+- Decompose Electra block attestations to prevent redundant packing. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14896)
+- Fixed use of deprecated rand.Seed. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14969)
+- Fixed build issue with SszGen where the go binary was not present in the $PATH. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14969)
+- fixed /eth/v1/config/spec displays BLOB_SIDECAR_SUBNET_COUNT,BLOB_SIDECAR_SUBNET_COUNT_ELECTRA. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15016)
+- Ensure that deleting a block from the database clears its entry in the slot->root db index. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15011)
+- Broadcasting BLS to execution changes should not use the request context in a go routine. Use context.Background() for the broadcasting go routine. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15019)
+- /eth/v1/validator/sync_committee_contribution should check for optimistic status and return a 503 if it's optimistic. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15022)
+- Fixes printing superfluous response.WriteHeader call from error in builder. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15025)
+- Fixes e2e run with builder having wrong gaslimit header due to not being set on eth1 nodes. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15025)
+- Fixed a bug in the event stream handler when processing payload attribute events where the timestamp and slot of the event would be based on the head rather than the current slot. [[PR]](https://github.com/prysmaticlabs/prysm/pull/14963)
+- Handle unaggregated attestations when decomposing Electra block attestations. [[PR]](https://github.com/prysmaticlabs/prysm/pull/15027)
+
 ## [v5.3.0](https://github.com/prysmaticlabs/prysm/compare/v5.2.0...v5.3.0) - 2025-02-12
 
 This release includes support for Pectra activation in the [Holesky](https://github.com/eth-clients/holesky) and [Sepolia](https://github.com/eth-clients/sepolia) testnets! The release contains many fixes for Electra that have been found in rigorous testing through devnets in the last few months.

CONTRIBUTING.md

@@ -4,7 +4,7 @@ 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/CTYGPUJ) 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.
@@ -15,15 +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.**
@@ -35,13 +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.**
 
@@ -129,7 +129,7 @@ All PRs must must include a changelog fragment file in the `changelog` directory
 
 **17. Create a pull request.**
 
-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 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/prysmaticlabs/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.
+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.**
 

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.
 
@@ -60,7 +60,7 @@ bazel build //beacon-chain --config=release
 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

@@ -10,7 +10,7 @@ This README details how to setup Prysm for interop testing for usage with other
 ## Installation & Setup
 
 1. Install [Bazel](https://docs.bazel.build/versions/master/install.html) **(Recommended)**
-2. `git clone https://github.com/prysmaticlabs/prysm && cd prysm`
+2. `git clone https://github.com/OffchainLabs/prysm && cd prysm`
 3. `bazel build //cmd/...`
 
 ## Starting from Genesis

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/OffchainLabs)
+[![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/OffchainLabs)** 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

@@ -255,7 +255,7 @@ filegroup(
     url = "https://github.com/ethereum/EIPs/archive/5480440fe51742ed23342b68cf106cefd427e39d.tar.gz",
 )
 
-consensus_spec_version = "v1.5.0-beta.2"
+consensus_spec_version = "v1.5.0-beta.5"
 
 bls_test_version = "v0.1.1"
 
@@ -271,7 +271,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    integrity = "sha256-X/bMxbKg1clo2aFEjBoeuFq/U+BF1eQopgRP/7nI3Qg=",
+    integrity = "sha256-H+Pt4z+HCVDnEBAv814yvsjR7f5l1IpumjFoTj2XnLE=",
     url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/general.tar.gz" % consensus_spec_version,
 )
 
@@ -287,7 +287,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    integrity = "sha256-WSxdri5OJGuNApW+odKle5UzToDyEOx+F3lMiqamJAg=",
+    integrity = "sha256-Dqiwf5BG7yYyURGf+i87AIdArAyztvcgjoi2kSxrGvo=",
     url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/minimal.tar.gz" % consensus_spec_version,
 )
 
@@ -303,7 +303,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    integrity = "sha256-LYE8l3y/zSt4YVrehrJ3ralqtgeYNildiIp+HR6+xAI=",
+    integrity = "sha256-xrmsFF243pzXHAjh1EQYKS9gtcwmtHK3wRZDSLlVVRk=",
     url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/mainnet.tar.gz" % consensus_spec_version,
 )
 
@@ -318,7 +318,7 @@ filegroup(
     visibility = ["//visibility:public"],
 )
     """,
-    integrity = "sha256-jvZQ90qcJMTOqMsPO7sgeEVQmewZTHcz7LVDkNqwTFQ=",
+    integrity = "sha256-c+gGapqifCvFtmtxfhOwieBDO2Syxp13GECWEpWM/Ho=",
     strip_prefix = "consensus-specs-" + consensus_spec_version[1:],
     url = "https://github.com/ethereum/consensus-specs/archive/refs/tags/%s.tar.gz" % consensus_spec_version,
 )
@@ -365,9 +365,25 @@ 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(
@@ -381,9 +397,25 @@ filegroup(
     visibility = ["//visibility:public"],
 )
 """,
-    integrity = "sha256-cY/UgpCcYEhQf7JefD65FI8tn/A+rAvKhcm2/qiVdqY=",
-    strip_prefix = "sepolia-f2c219a93c4491cee3d90c18f2f8e82aed850eab",
-    url = "https://github.com/eth-clients/sepolia/archive/f2c219a93c4491cee3d90c18f2f8e82aed850eab.tar.gz",  # 2024-09-19
+    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(

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 +1,19 @@
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["common.go"],
+    importpath = "github.com/OffchainLabs/prysm/v6/api/apiutil",
+    visibility = ["//visibility:public"],
+    deps = ["//consensus-types/primitives:go_default_library"],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["common_test.go"],
+    embed = [":go_default_library"],
+    deps = [
+        "//consensus-types/primitives:go_default_library",
+        "//testing/assert: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/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

@@ -5,14 +5,13 @@ go_library(
     srcs = [
         "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",
         "//consensus-types/primitives:go_default_library",
@@ -27,15 +26,10 @@ go_library(
 
 go_test(
     name = "go_default_test",
-    srcs = [
-        "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",
         "//testing/require:go_default_library",
-        "@org_uber_go_mock//gomock:go_default_library",
     ],
 )

api/client/beacon/client.go

@@ -11,17 +11,16 @@ import (
 	"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"
+	"github.com/OffchainLabs/prysm/v6/network/forks"
+	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"
 )
 
@@ -64,23 +63,6 @@ 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
-}
-
 // RenderGetBlockPath formats a block id into a path for the GetBlock API endpoint.
 func RenderGetBlockPath(id StateOrBlockId) string {
 	return path.Join(getSignedBlockPath, string(id))
@@ -114,8 +96,6 @@ 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
@@ -138,8 +118,6 @@ 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

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) {

api/client/beacon/health/BUILD.bazel

@@ -0,0 +1,20 @@
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "health.go",
+        "interfaces.go",
+        "mock.go",
+    ],
+    importpath = "github.com/OffchainLabs/prysm/v6/api/client/beacon/health",
+    visibility = ["//visibility:public"],
+    deps = ["@org_uber_go_mock//gomock:go_default_library"],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["health_test.go"],
+    embed = [":go_default_library"],
+    deps = ["@org_uber_go_mock//gomock:go_default_library"],
+)

api/client/beacon/health/health.go

@@ -1,20 +1,18 @@
-package beacon
+package health
 
 import (
 	"context"
 	"sync"
-
-	"github.com/prysmaticlabs/prysm/v5/api/client/beacon/iface"
 )
 
 type NodeHealthTracker struct {
 	isHealthy  *bool
 	healthChan chan bool
-	node       iface.HealthNode
+	node       Node
 	sync.RWMutex
 }
 
-func NewNodeHealthTracker(node iface.HealthNode) *NodeHealthTracker {
+func NewTracker(node Node) Tracker {
 	return &NodeHealthTracker{
 		node:       node,
 		healthChan: make(chan bool, 1),
@@ -26,7 +24,7 @@ func (n *NodeHealthTracker) HealthUpdates() <-chan bool {
 	return n.healthChan
 }
 
-func (n *NodeHealthTracker) IsHealthy() bool {
+func (n *NodeHealthTracker) IsHealthy(_ context.Context) bool {
 	n.RLock()
 	defer n.RUnlock()
 	if n.isHealthy == nil {

api/client/beacon/health/health_test.go

@@ -1,11 +1,10 @@
-package beacon
+package health
 
 import (
 	"context"
 	"sync"
 	"testing"
 
-	healthTesting "github.com/prysmaticlabs/prysm/v5/api/client/beacon/testing"
 	"go.uber.org/mock/gomock"
 )
 
@@ -24,7 +23,7 @@ func TestNodeHealth_IsHealthy(t *testing.T) {
 				isHealthy:  &tt.isHealthy,
 				healthChan: make(chan bool, 1),
 			}
-			if got := n.IsHealthy(); got != tt.want {
+			if got := n.IsHealthy(context.Background()); got != tt.want {
 				t.Errorf("IsHealthy() = %v, want %v", got, tt.want)
 			}
 		})
@@ -47,7 +46,7 @@ func TestNodeHealth_UpdateNodeHealth(t *testing.T) {
 		t.Run(tt.name, func(t *testing.T) {
 			ctrl := gomock.NewController(t)
 			defer ctrl.Finish()
-			client := healthTesting.NewMockHealthClient(ctrl)
+			client := NewMockHealthClient(ctrl)
 			client.EXPECT().IsHealthy(gomock.Any()).Return(tt.newStatus)
 			n := &NodeHealthTracker{
 				isHealthy:  &tt.initial,
@@ -80,8 +79,8 @@ func TestNodeHealth_UpdateNodeHealth(t *testing.T) {
 func TestNodeHealth_Concurrency(t *testing.T) {
 	ctrl := gomock.NewController(t)
 	defer ctrl.Finish()
-	client := healthTesting.NewMockHealthClient(ctrl)
-	n := NewNodeHealthTracker(client)
+	client := NewMockHealthClient(ctrl)
+	n := NewTracker(client)
 	var wg sync.WaitGroup
 
 	// Number of goroutines to spawn for both reading and writing
@@ -104,7 +103,7 @@ func TestNodeHealth_Concurrency(t *testing.T) {
 	for i := 0; i < numGoroutines; i++ {
 		go func() {
 			defer wg.Done()
-			_ = n.IsHealthy() // Just read the value
+			_ = n.IsHealthy(context.Background()) // Just read the value
 		}()
 	}
 

api/client/beacon/health/interfaces.go

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

api/client/beacon/health/mock.go

@@ -1,16 +1,15 @@
-package testing
+package health
 
 import (
 	"context"
 	"reflect"
 	"sync"
 
-	"github.com/prysmaticlabs/prysm/v5/api/client/beacon/iface"
 	"go.uber.org/mock/gomock"
 )
 
 var (
-	_ = iface.HealthNode(&MockHealthClient{})
+	_ = Node(&MockHealthClient{})
 )
 
 // MockHealthClient is a mock of HealthClient interface.

api/client/beacon/iface/BUILD.bazel

@@ -1,8 +0,0 @@
-load("@prysm//tools/go:def.bzl", "go_library")
-
-go_library(
-    name = "go_default_library",
-    srcs = ["health.go"],
-    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/beacon/iface",
-    visibility = ["//visibility:public"],
-)

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/builder/BUILD.bazel

@@ -8,7 +8,7 @@ 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/builder/bid.go

@@ -1,14 +1,14 @@
 package builder
 
 import (
+	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"
-	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"
 )
 
 // SignedBid is an interface describing the method set of a signed builder bid.

api/client/builder/client.go

@@ -12,18 +12,19 @@ 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/client"
-	"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"
-	"github.com/prysmaticlabs/prysm/v5/monitoring/tracing/trace"
-	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.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 )
@@ -35,9 +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)
@@ -52,6 +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) {
@@ -95,9 +107,10 @@ type BuilderClient interface {
 
 // 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).
@@ -139,7 +152,7 @@ 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) {
+func (c *Client) do(ctx context.Context, method string, path string, body io.Reader, opts ...reqOption) (res []byte, header http.Header, err error) {
 	ctx, span := trace.StartSpan(ctx, "builder.client.do")
 	defer func() {
 		tracing.AnnotateError(span, err)
@@ -155,10 +168,6 @@ func (c *Client) do(ctx context.Context, method string, path string, body io.Rea
 	if err != nil {
 		return
 	}
-	if method == http.MethodPost {
-		req.Header.Set("Content-Type", api.JsonMediaType)
-	}
-	req.Header.Set("Accept", api.JsonMediaType)
 	req.Header.Add("User-Agent", version.BuildData())
 	for _, o := range opts {
 		o(req)
@@ -187,6 +196,7 @@ func (c *Client) do(ctx context.Context, method string, path string, body io.Rea
 		err = errors.Wrap(err, "error reading http response body from builder server")
 		return
 	}
+	header = r.Header
 	return
 }
 
@@ -216,64 +226,145 @@ 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)
-	if err != nil {
-		return nil, err
+	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)
+		}
 	}
-	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)
+	data, header, err := c.do(ctx, http.MethodGet, path, nil, getOpts)
+	if err != nil {
+		return nil, errors.Wrap(err, "error getting header from builder server")
 	}
 
-	ver, err := version.FromString(strings.ToLower(v.Version))
+	bid, err := c.parseHeaderResponse(data, header)
 	if err != nil {
-		return nil, errors.Wrap(err, fmt.Sprintf("unsupported header version %s", strings.ToLower(v.Version)))
+		return nil, errors.Wrapf(
+			err,
+			"error rendering exec header template with slot=%d, parentHash=%#x, pubkey=%#x",
+			slot,
+			parentHash,
+			pubkey,
+		)
 	}
+	return bid, nil
+}
+
+func (c *Client) parseHeaderResponse(data []byte, header http.Header) (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",
+			)
+		}
+		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 {
-		hr := &ExecHeaderResponseElectra{}
-		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 WrappedSignedBuilderBidElectra(p)
+		return c.parseHeaderElectra(data)
 	}
 	if ver >= 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)
-		}
-		p, err := hr.ToProto()
-		if err != nil {
-			return nil, errors.Wrapf(err, "could not extract proto message from header")
-		}
-		return WrappedSignedBuilderBidDeneb(p)
+		return c.parseHeaderDeneb(data)
 	}
 	if ver >= 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)
+		return c.parseHeaderCapella(data)
 	}
 	if ver >= 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)
+		return c.parseHeaderBellatrix(data)
 	}
-	return nil, fmt.Errorf("unsupported header version %s", strings.ToLower(v.Version))
+
+	return nil, fmt.Errorf("unsupported header version %s", versionHeader)
+}
+
+func (c *Client) parseHeaderElectra(data []byte) (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()
+	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
@@ -288,70 +379,243 @@ func (c *Client) RegisterValidator(ctx context.Context, svr []*ethpb.SignedValid
 		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), 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))
-	if err != nil {
-		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")
 	}
-	log.WithField("registrationCount", len(svr)).Debug("Successfully registered validator(s) on builder")
-	return nil
+	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.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) {
+	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), 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
+}
+
+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.BlobsBundle, 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.BlobsBundle, error) {
+	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
@@ -360,11 +624,13 @@ 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
 	}
@@ -375,7 +641,10 @@ 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, getOpts)
 	return err
 }
 
@@ -390,6 +659,18 @@ func non200Err(response *http.Response) error {
 	}
 	msg := fmt.Sprintf("code=%d, url=%s, body=%s", 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/client_test.go

@@ -8,20 +8,19 @@ import (
 	"io"
 	"net/http"
 	"net/url"
-	"strconv"
 	"testing"
 
+	"github.com/OffchainLabs/prysm/v6/api"
+	"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/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	v1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	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/prysmaticlabs/go-bitfield"
-	"github.com/prysmaticlabs/prysm/v5/api"
-	"github.com/prysmaticlabs/prysm/v5/api/server/structs"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	v1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
 	log "github.com/sirupsen/logrus"
 )
 
@@ -88,39 +87,84 @@ func TestClient_RegisterValidator(t *testing.T) {
 	ctx := context.Background()
 	expectedBody := `[{"message":{"fee_recipient":"0x0000000000000000000000000000000000000000","gas_limit":"23","timestamp":"42","pubkey":"0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"},"signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}]`
 	expectedPath := "/eth/v1/builder/validators"
-	hc := &http.Client{
-		Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
-			require.Equal(t, api.JsonMediaType, r.Header.Get("Content-Type"))
-			require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
-			body, err := io.ReadAll(r.Body)
-			defer func() {
-				require.NoError(t, r.Body.Close())
-			}()
-			require.NoError(t, err)
-			require.Equal(t, expectedBody, string(body))
-			require.Equal(t, expectedPath, r.URL.Path)
-			require.Equal(t, http.MethodPost, r.Method)
-			return &http.Response{
-				StatusCode: http.StatusOK,
-				Body:       io.NopCloser(bytes.NewBuffer(nil)),
-				Request:    r.Clone(ctx),
-			}, nil
-		}),
-	}
-	c := &Client{
-		hc:      hc,
-		baseURL: &url.URL{Host: "localhost:3500", Scheme: "http"},
-	}
-	reg := &eth.SignedValidatorRegistrationV1{
-		Message: &eth.ValidatorRegistrationV1{
-			FeeRecipient: ezDecode(t, params.BeaconConfig().EthBurnAddressHex),
-			GasLimit:     23,
-			Timestamp:    42,
-			Pubkey:       ezDecode(t, "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"),
-		},
-		Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
-	}
-	require.NoError(t, c.RegisterValidator(ctx, []*eth.SignedValidatorRegistrationV1{reg}))
+	t.Run("JSON success", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Content-Type"))
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
+				body, err := io.ReadAll(r.Body)
+				defer func() {
+					require.NoError(t, r.Body.Close())
+				}()
+				require.NoError(t, err)
+				require.Equal(t, expectedBody, string(body))
+				require.Equal(t, expectedPath, r.URL.Path)
+				require.Equal(t, http.MethodPost, r.Method)
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Body:       io.NopCloser(bytes.NewBuffer(nil)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:      hc,
+			baseURL: &url.URL{Host: "localhost:3500", Scheme: "http"},
+		}
+		reg := &eth.SignedValidatorRegistrationV1{
+			Message: &eth.ValidatorRegistrationV1{
+				FeeRecipient: ezDecode(t, params.BeaconConfig().EthBurnAddressHex),
+				GasLimit:     23,
+				Timestamp:    42,
+				Pubkey:       ezDecode(t, "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"),
+			},
+			Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+		}
+		require.NoError(t, c.RegisterValidator(ctx, []*eth.SignedValidatorRegistrationV1{reg}))
+	})
+	t.Run("SSZ success", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Content-Type"))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				body, err := io.ReadAll(r.Body)
+				defer func() {
+					require.NoError(t, r.Body.Close())
+				}()
+				require.NoError(t, err)
+				request := &eth.SignedValidatorRegistrationV1{}
+				itemBytes := body[:request.SizeSSZ()]
+				require.NoError(t, request.UnmarshalSSZ(itemBytes))
+				jsRequest := structs.SignedValidatorRegistrationFromConsensus(request)
+				js, err := json.Marshal([]*structs.SignedValidatorRegistration{jsRequest})
+				require.NoError(t, err)
+
+				require.Equal(t, expectedBody, string(js))
+				require.Equal(t, expectedPath, r.URL.Path)
+				require.Equal(t, http.MethodPost, r.Method)
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Body:       io.NopCloser(bytes.NewBuffer(nil)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		reg := &eth.SignedValidatorRegistrationV1{
+			Message: &eth.ValidatorRegistrationV1{
+				FeeRecipient: ezDecode(t, params.BeaconConfig().EthBurnAddressHex),
+				GasLimit:     23,
+				Timestamp:    42,
+				Pubkey:       ezDecode(t, "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"),
+			},
+			Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+		}
+		require.NoError(t, c.RegisterValidator(ctx, []*eth.SignedValidatorRegistrationV1{reg}))
+	})
 }
 
 func TestClient_GetHeader(t *testing.T) {
@@ -176,6 +220,7 @@ func TestClient_GetHeader(t *testing.T) {
 		hc := &http.Client{
 			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
 				require.Equal(t, expectedPath, r.URL.Path)
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
 				return &http.Response{
 					StatusCode: http.StatusOK,
 					Body:       io.NopCloser(bytes.NewBufferString(testExampleHeaderResponse)),
@@ -207,9 +252,56 @@ func TestClient_GetHeader(t *testing.T) {
 		require.Equal(t, 0, value.Int.Cmp(primitives.WeiToBigInt(bid.Value())))
 		require.Equal(t, bidStr, primitives.WeiToBigInt(bid.Value()).String())
 	})
+	t.Run("bellatrix ssz", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				require.Equal(t, expectedPath, r.URL.Path)
+				epr := &ExecHeaderResponse{}
+				require.NoError(t, json.Unmarshal([]byte(testExampleHeaderResponse), epr))
+				pro, err := epr.ToProto()
+				require.NoError(t, err)
+				ssz, err := pro.MarshalSSZ()
+				require.NoError(t, err)
+				header := http.Header{}
+				header.Set(api.VersionHeader, "bellatrix")
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Header:     header,
+					Body:       io.NopCloser(bytes.NewBuffer(ssz)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		h, err := c.GetHeader(ctx, slot, bytesutil.ToBytes32(parentHash), bytesutil.ToBytes48(pubkey))
+		require.NoError(t, err)
+		expectedSig := ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505")
+		require.Equal(t, true, bytes.Equal(expectedSig, h.Signature()))
+		expectedTxRoot := ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
+		bid, err := h.Message()
+		require.NoError(t, err)
+		bidHeader, err := bid.Header()
+		require.NoError(t, err)
+		withdrawalsRoot, err := bidHeader.TransactionsRoot()
+		require.NoError(t, err)
+		require.Equal(t, true, bytes.Equal(expectedTxRoot, withdrawalsRoot))
+		require.Equal(t, uint64(1), bidHeader.GasUsed())
+		// this matches the value in the testExampleHeaderResponse
+		bidStr := "652312848583266388373324160190187140051835877600158453279131187530910662656"
+		value, err := stringToUint256(bidStr)
+		require.NoError(t, err)
+		require.Equal(t, 0, value.Int.Cmp(primitives.WeiToBigInt(bid.Value())))
+		require.Equal(t, bidStr, primitives.WeiToBigInt(bid.Value()).String())
+	})
 	t.Run("capella", func(t *testing.T) {
 		hc := &http.Client{
 			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
 				require.Equal(t, expectedPath, r.URL.Path)
 				return &http.Response{
 					StatusCode: http.StatusOK,
@@ -238,9 +330,52 @@ func TestClient_GetHeader(t *testing.T) {
 		require.Equal(t, 0, value.Int.Cmp(primitives.WeiToBigInt(bid.Value())))
 		require.Equal(t, bidStr, primitives.WeiToBigInt(bid.Value()).String())
 	})
+	t.Run("capella ssz", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				require.Equal(t, expectedPath, r.URL.Path)
+				epr := &ExecHeaderResponseCapella{}
+				require.NoError(t, json.Unmarshal([]byte(testExampleHeaderResponseCapella), epr))
+				pro, err := epr.ToProto()
+				require.NoError(t, err)
+				ssz, err := pro.MarshalSSZ()
+				require.NoError(t, err)
+				header := http.Header{}
+				header.Set(api.VersionHeader, "capella")
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Header:     header,
+					Body:       io.NopCloser(bytes.NewBuffer(ssz)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		h, err := c.GetHeader(ctx, slot, bytesutil.ToBytes32(parentHash), bytesutil.ToBytes48(pubkey))
+		require.NoError(t, err)
+		expectedWithdrawalsRoot := ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
+		bid, err := h.Message()
+		require.NoError(t, err)
+		bidHeader, err := bid.Header()
+		require.NoError(t, err)
+		withdrawalsRoot, err := bidHeader.WithdrawalsRoot()
+		require.NoError(t, err)
+		require.Equal(t, true, bytes.Equal(expectedWithdrawalsRoot, withdrawalsRoot))
+		bidStr := "652312848583266388373324160190187140051835877600158453279131187530910662656"
+		value, err := stringToUint256(bidStr)
+		require.NoError(t, err)
+		require.Equal(t, 0, value.Int.Cmp(primitives.WeiToBigInt(bid.Value())))
+		require.Equal(t, bidStr, primitives.WeiToBigInt(bid.Value()).String())
+	})
 	t.Run("deneb", func(t *testing.T) {
 		hc := &http.Client{
 			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
 				require.Equal(t, expectedPath, r.URL.Path)
 				return &http.Response{
 					StatusCode: http.StatusOK,
@@ -277,6 +412,56 @@ func TestClient_GetHeader(t *testing.T) {
 			require.Equal(t, len(kcgCommitments[i]) == 48, true)
 		}
 	})
+	t.Run("deneb ssz", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				require.Equal(t, expectedPath, r.URL.Path)
+				epr := &ExecHeaderResponseDeneb{}
+				require.NoError(t, json.Unmarshal([]byte(testExampleHeaderResponseDeneb), epr))
+				pro, err := epr.ToProto()
+				require.NoError(t, err)
+				ssz, err := pro.MarshalSSZ()
+				require.NoError(t, err)
+				header := http.Header{}
+				header.Set(api.VersionHeader, "deneb")
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Header:     header,
+					Body:       io.NopCloser(bytes.NewBuffer(ssz)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		h, err := c.GetHeader(ctx, slot, bytesutil.ToBytes32(parentHash), bytesutil.ToBytes48(pubkey))
+		require.NoError(t, err)
+		expectedWithdrawalsRoot := ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
+		bid, err := h.Message()
+		require.NoError(t, err)
+		bidHeader, err := bid.Header()
+		require.NoError(t, err)
+		withdrawalsRoot, err := bidHeader.WithdrawalsRoot()
+		require.NoError(t, err)
+		require.Equal(t, true, bytes.Equal(expectedWithdrawalsRoot, withdrawalsRoot))
+
+		bidStr := "652312848583266388373324160190187140051835877600158453279131187530910662656"
+		value, err := stringToUint256(bidStr)
+		require.NoError(t, err)
+		require.Equal(t, 0, value.Int.Cmp(primitives.WeiToBigInt(bid.Value())))
+		require.Equal(t, bidStr, primitives.WeiToBigInt(bid.Value()).String())
+		dbid, ok := bid.(builderBidDeneb)
+		require.Equal(t, true, ok)
+		kcgCommitments := dbid.BlobKzgCommitments()
+		require.Equal(t, len(kcgCommitments) > 0, true)
+		for i := range kcgCommitments {
+			require.Equal(t, len(kcgCommitments[i]) == 48, true)
+		}
+	})
 	t.Run("deneb, too many kzg commitments", func(t *testing.T) {
 		hc := &http.Client{
 			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
@@ -293,11 +478,12 @@ func TestClient_GetHeader(t *testing.T) {
 			baseURL: &url.URL{Host: "localhost:3500", Scheme: "http"},
 		}
 		_, err := c.GetHeader(ctx, slot, bytesutil.ToBytes32(parentHash), bytesutil.ToBytes48(pubkey))
-		require.ErrorContains(t, "could not extract proto message from header: too many blob commitments: 7", err)
+		require.ErrorContains(t, "could not convert ExecHeaderResponseDeneb to proto: too many blob commitments: 7", err)
 	})
 	t.Run("electra", func(t *testing.T) {
 		hc := &http.Client{
 			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
 				require.Equal(t, expectedPath, r.URL.Path)
 				return &http.Response{
 					StatusCode: http.StatusOK,
@@ -338,6 +524,61 @@ func TestClient_GetHeader(t *testing.T) {
 		require.Equal(t, 1, len(requests.Withdrawals))
 		require.Equal(t, 1, len(requests.Consolidations))
 
+	})
+	t.Run("electra ssz", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				require.Equal(t, expectedPath, r.URL.Path)
+				epr := &ExecHeaderResponseElectra{}
+				require.NoError(t, json.Unmarshal([]byte(testExampleHeaderResponseElectra), epr))
+				pro, err := epr.ToProto()
+				require.NoError(t, err)
+				ssz, err := pro.MarshalSSZ()
+				require.NoError(t, err)
+				header := http.Header{}
+				header.Set(api.VersionHeader, "electra")
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Header:     header,
+					Body:       io.NopCloser(bytes.NewBuffer(ssz)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		h, err := c.GetHeader(ctx, slot, bytesutil.ToBytes32(parentHash), bytesutil.ToBytes48(pubkey))
+		require.NoError(t, err)
+		expectedWithdrawalsRoot := ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
+		bid, err := h.Message()
+		require.NoError(t, err)
+		bidHeader, err := bid.Header()
+		require.NoError(t, err)
+		withdrawalsRoot, err := bidHeader.WithdrawalsRoot()
+		require.NoError(t, err)
+		require.Equal(t, true, bytes.Equal(expectedWithdrawalsRoot, withdrawalsRoot))
+
+		bidStr := "652312848583266388373324160190187140051835877600158453279131187530910662656"
+		value, err := stringToUint256(bidStr)
+		require.NoError(t, err)
+		require.Equal(t, 0, value.Int.Cmp(primitives.WeiToBigInt(bid.Value())))
+		require.Equal(t, bidStr, primitives.WeiToBigInt(bid.Value()).String())
+		ebid, ok := bid.(builderBidElectra)
+		require.Equal(t, true, ok)
+		kcgCommitments := ebid.BlobKzgCommitments()
+		require.Equal(t, len(kcgCommitments) > 0, true)
+		for i := range kcgCommitments {
+			require.Equal(t, len(kcgCommitments[i]) == 48, true)
+		}
+		requests := ebid.ExecutionRequests()
+		require.Equal(t, 1, len(requests.Deposits))
+		require.Equal(t, 1, len(requests.Withdrawals))
+		require.Equal(t, 1, len(requests.Consolidations))
+
 	})
 	t.Run("unsupported version", func(t *testing.T) {
 		hc := &http.Client{
@@ -390,11 +631,51 @@ func TestSubmitBlindedBlock(t *testing.T) {
 		require.Equal(t, fmt.Sprintf("%#x", bfpg.SSZBytes()), fmt.Sprintf("%#x", ep.BaseFeePerGas()))
 		require.Equal(t, uint64(1), ep.GasLimit())
 	})
+	t.Run("bellatrix ssz", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
+				require.Equal(t, "bellatrix", r.Header.Get(api.VersionHeader))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Content-Type"))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				epr := &ExecutionPayloadResponse{}
+				require.NoError(t, json.Unmarshal([]byte(testExampleExecutionPayload), epr))
+				ep := &ExecutionPayload{}
+				require.NoError(t, json.Unmarshal(epr.Data, ep))
+				pro, err := ep.ToProto()
+				require.NoError(t, err)
+				ssz, err := pro.MarshalSSZ()
+				require.NoError(t, err)
+				header := http.Header{}
+				header.Set(api.VersionHeader, "bellatrix")
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Header:     header,
+					Body:       io.NopCloser(bytes.NewBuffer(ssz)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		sbbb, err := blocks.NewSignedBeaconBlock(testSignedBlindedBeaconBlockBellatrix(t))
+		require.NoError(t, err)
+		ep, _, err := c.SubmitBlindedBlock(ctx, sbbb)
+		require.NoError(t, err)
+		require.Equal(t, true, bytes.Equal(ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"), ep.ParentHash()))
+		bfpg, err := stringToUint256("452312848583266388373324160190187140051835877600158453279131187530910662656")
+		require.NoError(t, err)
+		require.Equal(t, fmt.Sprintf("%#x", bfpg.SSZBytes()), fmt.Sprintf("%#x", ep.BaseFeePerGas()))
+		require.Equal(t, uint64(1), ep.GasLimit())
+	})
 	t.Run("capella", func(t *testing.T) {
 		hc := &http.Client{
 			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
 				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
-				require.Equal(t, "capella", r.Header.Get("Eth-Consensus-Version"))
+				require.Equal(t, "capella", r.Header.Get(api.VersionHeader))
 				require.Equal(t, api.JsonMediaType, r.Header.Get("Content-Type"))
 				require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
 				return &http.Response{
@@ -420,12 +701,54 @@ func TestSubmitBlindedBlock(t *testing.T) {
 		assert.DeepEqual(t, ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943"), withdrawals[0].Address)
 		assert.Equal(t, uint64(1), withdrawals[0].Amount)
 	})
+	t.Run("capella ssz", func(t *testing.T) {
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
+				require.Equal(t, "capella", r.Header.Get(api.VersionHeader))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Content-Type"))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				epr := &ExecutionPayloadResponse{}
+				require.NoError(t, json.Unmarshal([]byte(testExampleExecutionPayloadCapella), epr))
+				ep := &ExecutionPayloadCapella{}
+				require.NoError(t, json.Unmarshal(epr.Data, ep))
+				pro, err := ep.ToProto()
+				require.NoError(t, err)
+				ssz, err := pro.MarshalSSZ()
+				require.NoError(t, err)
+				header := http.Header{}
+				header.Set(api.VersionHeader, "capella")
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Header:     header,
+					Body:       io.NopCloser(bytes.NewBuffer(ssz)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		sbb, err := blocks.NewSignedBeaconBlock(testSignedBlindedBeaconBlockCapella(t))
+		require.NoError(t, err)
+		ep, _, err := c.SubmitBlindedBlock(ctx, sbb)
+		require.NoError(t, err)
+		withdrawals, err := ep.Withdrawals()
+		require.NoError(t, err)
+		require.Equal(t, 1, len(withdrawals))
+		assert.Equal(t, uint64(1), withdrawals[0].Index)
+		assert.Equal(t, primitives.ValidatorIndex(1), withdrawals[0].ValidatorIndex)
+		assert.DeepEqual(t, ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943"), withdrawals[0].Address)
+		assert.Equal(t, uint64(1), withdrawals[0].Amount)
+	})
 	t.Run("deneb", func(t *testing.T) {
 		test := testSignedBlindedBeaconBlockDeneb(t)
 		hc := &http.Client{
 			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
 				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
-				require.Equal(t, "deneb", r.Header.Get("Eth-Consensus-Version"))
+				require.Equal(t, "deneb", r.Header.Get(api.VersionHeader))
 				require.Equal(t, api.JsonMediaType, r.Header.Get("Content-Type"))
 				require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
 				var req structs.SignedBlindedBeaconBlockDeneb
@@ -460,6 +783,140 @@ func TestSubmitBlindedBlock(t *testing.T) {
 		assert.Equal(t, uint64(1), withdrawals[0].Amount)
 		require.NotNil(t, blobBundle)
 	})
+	t.Run("deneb ssz", func(t *testing.T) {
+		test := testSignedBlindedBeaconBlockDeneb(t)
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
+				require.Equal(t, "deneb", r.Header.Get(api.VersionHeader))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Content-Type"))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				epr := &ExecPayloadResponseDeneb{}
+				require.NoError(t, json.Unmarshal([]byte(testExampleExecutionPayloadDeneb), epr))
+				pro, blob, err := epr.ToProto()
+				require.NoError(t, err)
+				combined := &v1.ExecutionPayloadDenebAndBlobsBundle{
+					Payload:     pro,
+					BlobsBundle: blob,
+				}
+				ssz, err := combined.MarshalSSZ()
+				require.NoError(t, err)
+				header := http.Header{}
+				header.Set(api.VersionHeader, "deneb")
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Header:     header,
+					Body:       io.NopCloser(bytes.NewBuffer(ssz)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		sbb, err := blocks.NewSignedBeaconBlock(test)
+		require.NoError(t, err)
+
+		ep, blobBundle, err := c.SubmitBlindedBlock(ctx, sbb)
+		require.NoError(t, err)
+		withdrawals, err := ep.Withdrawals()
+		require.NoError(t, err)
+		require.Equal(t, 1, len(withdrawals))
+		assert.Equal(t, uint64(1), withdrawals[0].Index)
+		assert.Equal(t, primitives.ValidatorIndex(1), withdrawals[0].ValidatorIndex)
+		assert.DeepEqual(t, ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943"), withdrawals[0].Address)
+		assert.Equal(t, uint64(1), withdrawals[0].Amount)
+		require.NotNil(t, blobBundle)
+	})
+	t.Run("electra", func(t *testing.T) {
+		test := testSignedBlindedBeaconBlockElectra(t)
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
+				require.Equal(t, "electra", r.Header.Get(api.VersionHeader))
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Content-Type"))
+				require.Equal(t, api.JsonMediaType, r.Header.Get("Accept"))
+				var req structs.SignedBlindedBeaconBlockElectra
+				err := json.NewDecoder(r.Body).Decode(&req)
+				require.NoError(t, err)
+				block, err := req.ToConsensus()
+				require.NoError(t, err)
+				require.DeepEqual(t, block, test)
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Body:       io.NopCloser(bytes.NewBufferString(testExampleExecutionPayloadDeneb)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:      hc,
+			baseURL: &url.URL{Host: "localhost:3500", Scheme: "http"},
+		}
+
+		sbb, err := blocks.NewSignedBeaconBlock(test)
+		require.NoError(t, err)
+
+		ep, blobBundle, err := c.SubmitBlindedBlock(ctx, sbb)
+		require.NoError(t, err)
+		withdrawals, err := ep.Withdrawals()
+		require.NoError(t, err)
+		require.Equal(t, 1, len(withdrawals))
+		assert.Equal(t, uint64(1), withdrawals[0].Index)
+		assert.Equal(t, primitives.ValidatorIndex(1), withdrawals[0].ValidatorIndex)
+		assert.DeepEqual(t, ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943"), withdrawals[0].Address)
+		assert.Equal(t, uint64(1), withdrawals[0].Amount)
+		require.NotNil(t, blobBundle)
+	})
+	t.Run("electra ssz", func(t *testing.T) {
+		test := testSignedBlindedBeaconBlockElectra(t)
+		hc := &http.Client{
+			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
+				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
+				require.Equal(t, "electra", r.Header.Get(api.VersionHeader))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Content-Type"))
+				require.Equal(t, api.OctetStreamMediaType, r.Header.Get("Accept"))
+				epr := &ExecPayloadResponseDeneb{}
+				require.NoError(t, json.Unmarshal([]byte(testExampleExecutionPayloadDeneb), epr))
+				pro, blob, err := epr.ToProto()
+				require.NoError(t, err)
+				combined := &v1.ExecutionPayloadDenebAndBlobsBundle{
+					Payload:     pro,
+					BlobsBundle: blob,
+				}
+				ssz, err := combined.MarshalSSZ()
+				require.NoError(t, err)
+				header := http.Header{}
+				header.Set(api.VersionHeader, "electra")
+				return &http.Response{
+					StatusCode: http.StatusOK,
+					Header:     header,
+					Body:       io.NopCloser(bytes.NewBuffer(ssz)),
+					Request:    r.Clone(ctx),
+				}, nil
+			}),
+		}
+		c := &Client{
+			hc:         hc,
+			baseURL:    &url.URL{Host: "localhost:3500", Scheme: "http"},
+			sszEnabled: true,
+		}
+		sbb, err := blocks.NewSignedBeaconBlock(test)
+		require.NoError(t, err)
+
+		ep, blobBundle, err := c.SubmitBlindedBlock(ctx, sbb)
+		require.NoError(t, err)
+		withdrawals, err := ep.Withdrawals()
+		require.NoError(t, err)
+		require.Equal(t, 1, len(withdrawals))
+		assert.Equal(t, uint64(1), withdrawals[0].Index)
+		assert.Equal(t, primitives.ValidatorIndex(1), withdrawals[0].ValidatorIndex)
+		assert.DeepEqual(t, ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943"), withdrawals[0].Address)
+		assert.Equal(t, uint64(1), withdrawals[0].Amount)
+		require.NotNil(t, blobBundle)
+	})
 	t.Run("mismatched versions, expected bellatrix got capella", func(t *testing.T) {
 		hc := &http.Client{
 			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
@@ -586,7 +1043,13 @@ func testSignedBlindedBeaconBlockBellatrix(t *testing.T) *eth.SignedBlindedBeaco
 				},
 				Deposits: []*eth.Deposit{
 					{
-						Proof: [][]byte{ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")},
+						Proof: func() [][]byte {
+							b := make([][]byte, 33)
+							for i := range b {
+								b[i] = ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
+							}
+							return b
+						}(),
 						Data: &eth.Deposit_Data{
 							PublicKey:             ezDecode(t, "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"),
 							WithdrawalCredentials: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
@@ -605,8 +1068,8 @@ func testSignedBlindedBeaconBlockBellatrix(t *testing.T) *eth.SignedBlindedBeaco
 					},
 				},
 				SyncAggregate: &eth.SyncAggregate{
-					SyncCommitteeSignature: make([]byte, 48),
-					SyncCommitteeBits:      bitfield.Bitvector512{0x01},
+					SyncCommitteeSignature: make([]byte, 96),
+					SyncCommitteeBits:      make(bitfield.Bitvector512, 64),
 				},
 				ExecutionPayloadHeader: &v1.ExecutionPayloadHeader{
 					ParentHash:       ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
@@ -620,7 +1083,7 @@ func testSignedBlindedBeaconBlockBellatrix(t *testing.T) *eth.SignedBlindedBeaco
 					GasUsed:          1,
 					Timestamp:        1,
 					ExtraData:        ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
-					BaseFeePerGas:    []byte(strconv.FormatUint(1, 10)),
+					BaseFeePerGas:    ezDecode(t, "0x4523128485832663883733241601901871400518358776001584532791311875"),
 					BlockHash:        ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
 					TransactionsRoot: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
 				},
@@ -728,7 +1191,13 @@ func testSignedBlindedBeaconBlockCapella(t *testing.T) *eth.SignedBlindedBeaconB
 				},
 				Deposits: []*eth.Deposit{
 					{
-						Proof: [][]byte{ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")},
+						Proof: func() [][]byte {
+							b := make([][]byte, 33)
+							for i := range b {
+								b[i] = ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
+							}
+							return b
+						}(),
 						Data: &eth.Deposit_Data{
 							PublicKey:             ezDecode(t, "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"),
 							WithdrawalCredentials: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
@@ -747,8 +1216,8 @@ func testSignedBlindedBeaconBlockCapella(t *testing.T) *eth.SignedBlindedBeaconB
 					},
 				},
 				SyncAggregate: &eth.SyncAggregate{
-					SyncCommitteeSignature: make([]byte, 48),
-					SyncCommitteeBits:      bitfield.Bitvector512{0x01},
+					SyncCommitteeSignature: make([]byte, 96),
+					SyncCommitteeBits:      make(bitfield.Bitvector512, 64),
 				},
 				ExecutionPayloadHeader: &v1.ExecutionPayloadHeaderCapella{
 					ParentHash:       ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
@@ -762,7 +1231,7 @@ func testSignedBlindedBeaconBlockCapella(t *testing.T) *eth.SignedBlindedBeaconB
 					GasUsed:          1,
 					Timestamp:        1,
 					ExtraData:        ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
-					BaseFeePerGas:    []byte(strconv.FormatUint(1, 10)),
+					BaseFeePerGas:    ezDecode(t, "0x4523128485832663883733241601901871400518358776001584532791311875"),
 					BlockHash:        ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
 					TransactionsRoot: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
 					WithdrawalsRoot:  ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
@@ -875,7 +1344,13 @@ func testSignedBlindedBeaconBlockDeneb(t *testing.T) *eth.SignedBlindedBeaconBlo
 				},
 				Deposits: []*eth.Deposit{
 					{
-						Proof: [][]byte{ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")},
+						Proof: func() [][]byte {
+							b := make([][]byte, 33)
+							for i := range b {
+								b[i] = ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
+							}
+							return b
+						}(),
 						Data: &eth.Deposit_Data{
 							PublicKey:             ezDecode(t, "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"),
 							WithdrawalCredentials: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
@@ -922,6 +1397,163 @@ func testSignedBlindedBeaconBlockDeneb(t *testing.T) *eth.SignedBlindedBeaconBlo
 	}
 }
 
+func testSignedBlindedBeaconBlockElectra(t *testing.T) *eth.SignedBlindedBeaconBlockElectra {
+	basebytes, err := bytesutil.Uint256ToSSZBytes("14074904626401341155369551180448584754667373453244490859944217516317499064576")
+	if err != nil {
+		log.Error(err)
+	}
+	return &eth.SignedBlindedBeaconBlockElectra{
+		Message: &eth.BlindedBeaconBlockElectra{
+			Slot:          1,
+			ProposerIndex: 1,
+			ParentRoot:    ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+			StateRoot:     ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+			Body: &eth.BlindedBeaconBlockBodyElectra{
+				RandaoReveal: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+				Eth1Data: &eth.Eth1Data{
+					DepositRoot:  ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+					DepositCount: 1,
+					BlockHash:    ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+				},
+				Graffiti: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+				ProposerSlashings: []*eth.ProposerSlashing{
+					{
+						Header_1: &eth.SignedBeaconBlockHeader{
+							Header: &eth.BeaconBlockHeader{
+								Slot:          1,
+								ProposerIndex: 1,
+								ParentRoot:    ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								StateRoot:     ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								BodyRoot:      ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+							},
+							Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+						},
+						Header_2: &eth.SignedBeaconBlockHeader{
+							Header: &eth.BeaconBlockHeader{
+								Slot:          1,
+								ProposerIndex: 1,
+								ParentRoot:    ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								StateRoot:     ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								BodyRoot:      ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+							},
+							Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+						},
+					},
+				},
+				AttesterSlashings: []*eth.AttesterSlashingElectra{
+					{
+						Attestation_1: &eth.IndexedAttestationElectra{
+							AttestingIndices: []uint64{1},
+							Data: &eth.AttestationData{
+								Slot:            1,
+								CommitteeIndex:  1,
+								BeaconBlockRoot: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								Source: &eth.Checkpoint{
+									Epoch: 1,
+									Root:  ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								},
+								Target: &eth.Checkpoint{
+									Epoch: 1,
+									Root:  ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								},
+							},
+							Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+						},
+						Attestation_2: &eth.IndexedAttestationElectra{
+							AttestingIndices: []uint64{1},
+							Data: &eth.AttestationData{
+								Slot:            1,
+								CommitteeIndex:  1,
+								BeaconBlockRoot: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								Source: &eth.Checkpoint{
+									Epoch: 1,
+									Root:  ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								},
+								Target: &eth.Checkpoint{
+									Epoch: 1,
+									Root:  ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+								},
+							},
+							Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+						},
+					},
+				},
+				Attestations: []*eth.AttestationElectra{
+					{
+						AggregationBits: bitfield.Bitlist{0x01},
+						Data: &eth.AttestationData{
+							Slot:            1,
+							CommitteeIndex:  1,
+							BeaconBlockRoot: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+							Source: &eth.Checkpoint{
+								Epoch: 1,
+								Root:  ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+							},
+							Target: &eth.Checkpoint{
+								Epoch: 1,
+								Root:  ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+							},
+						},
+						CommitteeBits: make(bitfield.Bitvector64, 8),
+						Signature:     ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+					},
+				},
+				Deposits: []*eth.Deposit{
+					{
+						Proof: func() [][]byte {
+							b := make([][]byte, 33)
+							for i := range b {
+								b[i] = ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2")
+							}
+							return b
+						}(),
+						Data: &eth.Deposit_Data{
+							PublicKey:             ezDecode(t, "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"),
+							WithdrawalCredentials: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+							Amount:                1,
+							Signature:             ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+						},
+					},
+				},
+				VoluntaryExits: []*eth.SignedVoluntaryExit{
+					{
+						Exit: &eth.VoluntaryExit{
+							Epoch:          1,
+							ValidatorIndex: 1,
+						},
+						Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+					},
+				},
+				SyncAggregate: &eth.SyncAggregate{
+					SyncCommitteeSignature: make([]byte, 96),
+					SyncCommitteeBits:      ezDecode(t, "0x6451e9f951ebf05edc01de67e593484b672877054f055903ff0df1a1a945cf30ca26bb4d4b154f94a1bc776bcf5d0efb3603e1f9b8ee2499ccdcfe2a18cef458"),
+				},
+				ExecutionRequests: &v1.ExecutionRequests{},
+				ExecutionPayloadHeader: &v1.ExecutionPayloadHeaderDeneb{
+					ParentHash:       ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+					FeeRecipient:     ezDecode(t, "0xabcf8e0d4e9587369b2301d0790347320302cc09"),
+					StateRoot:        ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+					ReceiptsRoot:     ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+					LogsBloom:        ezDecode(t, "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
+					PrevRandao:       ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+					BlockNumber:      1,
+					GasLimit:         1,
+					GasUsed:          1,
+					Timestamp:        1,
+					ExtraData:        ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+					BaseFeePerGas:    basebytes,
+					BlockHash:        ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+					TransactionsRoot: ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+					WithdrawalsRoot:  ezDecode(t, "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"),
+					BlobGasUsed:      1,
+					ExcessBlobGas:    2,
+				},
+			},
+		},
+		Signature: ezDecode(t, "0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"),
+	}
+}
+
 func TestRequestLogger(t *testing.T) {
 	wo := WithObserver(&requestLogger{})
 	c, err := NewClient("localhost:3500", wo)

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.

api/client/builder/types.go

@@ -7,19 +7,19 @@ import (
 	"strconv"
 	"strings"
 
+	"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"
+	types "github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	"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/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/config/params"
-	consensusblocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	types "github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	"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"
 	"google.golang.org/protobuf/proto"
 )
 

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 {

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/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

@@ -7,9 +7,9 @@ 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"
 )
 

api/client/event/event_stream_test.go

@@ -8,7 +8,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 	log "github.com/sirupsen/logrus"
 )
 

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/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/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",

api/grpc/grpcutils_test.go

@@ -4,8 +4,8 @@ import (
 	"context"
 	"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"
 	logTest "github.com/sirupsen/logrus/hooks/test"
 	"google.golang.org/grpc/metadata"
 )

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

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

api/server/httprest/options.go

@@ -5,7 +5,7 @@ import (
 
 	"net/http"
 
-	"github.com/prysmaticlabs/prysm/v5/api/server/middleware"
+	"github.com/OffchainLabs/prysm/v6/api/server/middleware"
 )
 
 // Option is a http rest server functional parameter type.

api/server/httprest/server.go

@@ -5,9 +5,9 @@ import (
 	"net/http"
 	"time"
 
+	"github.com/OffchainLabs/prysm/v6/api/server/middleware"
+	"github.com/OffchainLabs/prysm/v6/runtime"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/api/server/middleware"
-	"github.com/prysmaticlabs/prysm/v5/runtime"
 )
 
 var _ runtime.Service = (*Server)(nil)

api/server/httprest/server_test.go

@@ -10,9 +10,9 @@ import (
 	"net/url"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/cmd/beacon-chain/flags"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"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"
 )

api/server/middleware/BUILD.bazel

@@ -6,7 +6,7 @@ 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_rs_cors//:go_default_library"],
 )

api/server/middleware/middleware_test.go

@@ -5,8 +5,8 @@ import (
 	"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"
 )
 
 func TestNormalizeQueryValuesHandler(t *testing.T) {

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

@@ -24,7 +24,7 @@ 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",

api/server/structs/conversions.go

@@ -4,20 +4,20 @@ 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/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/config/params"
-	"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"
-	ethv1 "github.com/prysmaticlabs/prysm/v5/proto/eth/v1"
-	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 )
 
 var errNilValue = errors.New("nil value")

api/server/structs/conversions_blob.go

@@ -3,9 +3,9 @@ package structs
 import (
 	"strconv"
 
-	"github.com/prysmaticlabs/prysm/v5/api/server"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
+	"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) {

api/server/structs/conversions_block.go

@@ -4,17 +4,17 @@ import (
 	"fmt"
 	"strconv"
 
+	"github.com/OffchainLabs/prysm/v6/api/server"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
+	"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"
+	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/interfaces"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/container/slice"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 )
 
 var ErrUnsupportedConversion = errors.New("Could not determine api struct type to use for value")

api/server/structs/conversions_block_execution.go

@@ -4,15 +4,15 @@ 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/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/prysmaticlabs/prysm/v5/api/server"
-	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/container/slice"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
 )
 
 // ----------------------------------------------------------------------------

api/server/structs/conversions_block_execution_test.go

@@ -4,10 +4,10 @@ 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"
-	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
 )
 
 func fillByteSlice(sliceLength int, value byte) []byte {

api/server/structs/conversions_lightclient.go

@@ -4,11 +4,11 @@ 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"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
-	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	"github.com/prysmaticlabs/prysm/v5/runtime/version"
 )
 
 func LightClientUpdateFromConsensus(update interfaces.LightClientUpdate) (*LightClientUpdate, error) {

api/server/structs/conversions_state.go

@@ -4,9 +4,9 @@ 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")

api/server/structs/conversions_test.go

@@ -3,8 +3,8 @@ 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/require"
 )
 
 func TestDepositSnapshotFromConsensus(t *testing.T) {

api/server/structs/endpoints_beacon.go

@@ -78,8 +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 {
@@ -100,6 +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"`
@@ -112,6 +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"`
 }
@@ -251,6 +263,13 @@ type ChainHead struct {
 	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"`

api/server/structs/endpoints_events.go

@@ -20,6 +20,11 @@ type BlockEvent struct {
 	ExecutionOptimistic bool   `json:"execution_optimistic"`
 }
 
+type BlockGossipEvent struct {
+	Slot  string `json:"slot"`
+	Block string `json:"block"`
+}
+
 type AggregatedAttEventSource struct {
 	Aggregate *Attestation `json:"aggregate"`
 }

api/server/structs/endpoints_validator.go

@@ -3,7 +3,7 @@ package structs
 import (
 	"encoding/json"
 
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
 )
 
 type AggregateAttestationResponse struct {

async/BUILD.bazel

@@ -8,7 +8,7 @@ go_library(
         "multilock.go",
         "scatter.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/async",
+    importpath = "github.com/OffchainLabs/prysm/v6/async",
     visibility = ["//visibility:public"],
     deps = ["@com_github_sirupsen_logrus//:go_default_library"],
 )

async/abool/BUILD.bazel

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

async/benchmark_test.go

@@ -6,8 +6,8 @@ import (
 	"sync"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/async"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/async"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 	log "github.com/sirupsen/logrus"
 )
 

async/debounce_test.go

@@ -7,10 +7,10 @@ import (
 	"testing"
 	"time"
 
-	"github.com/prysmaticlabs/prysm/v5/async"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
-	"github.com/prysmaticlabs/prysm/v5/testing/util"
+	"github.com/OffchainLabs/prysm/v6/async"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
 )
 
 func TestDebounce_NoEvents(t *testing.T) {

async/event/BUILD.bazel

@@ -7,7 +7,7 @@ go_library(
         "interface.go",
         "subscription.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/async/event",
+    importpath = "github.com/OffchainLabs/prysm/v6/async/event",
     visibility = ["//visibility:public"],
     deps = [
         "//time/mclock:go_default_library",

async/event/example_scope_test.go

@@ -20,7 +20,7 @@ import (
 	"fmt"
 	"sync"
 
-	"github.com/prysmaticlabs/prysm/v5/async/event"
+	"github.com/OffchainLabs/prysm/v6/async/event"
 )
 
 // This example demonstrates how SubscriptionScope can be used to control the lifetime of

async/event/example_subscription_test.go

@@ -19,7 +19,7 @@ package event_test
 import (
 	"fmt"
 
-	"github.com/prysmaticlabs/prysm/v5/async/event"
+	"github.com/OffchainLabs/prysm/v6/async/event"
 )
 
 func ExampleNewSubscription() {

async/event/subscription.go

@@ -21,7 +21,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/prysmaticlabs/prysm/v5/time/mclock"
+	"github.com/OffchainLabs/prysm/v6/time/mclock"
 )
 
 // waitQuotient is divided against the max backoff time, in order to have N requests based on the full
@@ -154,7 +154,7 @@ retry:
 				continue retry
 			}
 			if sub == nil {
-				panic("event: ResubscribeFunc returned nil subscription and no error")
+				panic("event: ResubscribeFunc returned nil subscription and no error") // lint:nopanic -- This should never happen.
 			}
 			return sub
 		case <-s.unsub:

async/event/subscription_test.go

@@ -23,7 +23,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 )
 
 var errInts = errors.New("error in subscribeInts")

async/every_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/prysmaticlabs/prysm/v5/async"
+	"github.com/OffchainLabs/prysm/v6/async"
 )
 
 func TestEveryRuns(t *testing.T) {

async/scatter_test.go

@@ -5,9 +5,9 @@ import (
 	"sync"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/async"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/OffchainLabs/prysm/v6/async"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 )
 
 func TestDouble(t *testing.T) {

beacon-chain/blockchain/BUILD.bazel

@@ -30,7 +30,7 @@ go_library(
         "tracked_proposer.go",
         "weak_subjectivity_checks.go",
     ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/beacon-chain/blockchain",
+    importpath = "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain",
     visibility = [
         "//beacon-chain:__subpackages__",
         "//cmd/beacon-chain:__subpackages__",
@@ -70,6 +70,7 @@ go_library(
         "//beacon-chain/startup:go_default_library",
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/stategen:go_default_library",
+        "//beacon-chain/verification:go_default_library",
         "//config/features:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",
@@ -166,6 +167,7 @@ go_test(
         "//beacon-chain/state:go_default_library",
         "//beacon-chain/state/state-native:go_default_library",
         "//beacon-chain/state/stategen:go_default_library",
+        "//beacon-chain/verification:go_default_library",
         "//config/features:go_default_library",
         "//config/fieldparams:go_default_library",
         "//config/params:go_default_library",

beacon-chain/blockchain/chain_info.go

@@ -5,21 +5,21 @@ import (
 	"context"
 	"time"
 
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
+	f "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice"
+	doublylinkedtree "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/doubly-linked-tree"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	consensus_blocks "github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/forkchoice"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
-	f "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice"
-	doublylinkedtree "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	consensus_blocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/forkchoice"
-	"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/monitoring/tracing/trace"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/time/slots"
 )
 
 // ChainInfoFetcher defines a common interface for methods in blockchain service which
@@ -51,6 +51,7 @@ type ForkchoiceFetcher interface {
 	ProposerBoost() [32]byte
 	RecentBlockSlot(root [32]byte) (primitives.Slot, error)
 	IsCanonical(ctx context.Context, blockRoot [32]byte) (bool, error)
+	DependentRoot(primitives.Epoch) ([32]byte, error)
 }
 
 // TimeFetcher retrieves the Ethereum consensus data that's related to time.

beacon-chain/blockchain/chain_info_forkchoice.go

@@ -3,10 +3,13 @@ package blockchain
 import (
 	"context"
 
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	consensus_blocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/forkchoice"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	consensus_blocks "github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/forkchoice"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/pkg/errors"
 )
 
 // CachedHeadRoot returns the corresponding value from Forkchoice
@@ -100,3 +103,33 @@ func (s *Service) ParentRoot(root [32]byte) ([32]byte, error) {
 	defer s.cfg.ForkChoiceStore.RUnlock()
 	return s.cfg.ForkChoiceStore.ParentRoot(root)
 }
+
+// hashForGenesisBlock returns the right hash for the genesis block
+func (s *Service) hashForGenesisBlock(ctx context.Context, root [32]byte) ([]byte, error) {
+	genRoot, err := s.cfg.BeaconDB.GenesisBlockRoot(ctx)
+	if err != nil {
+		return nil, errors.Wrap(err, "could not get genesis block root")
+	}
+	if root != genRoot {
+		return nil, errNotGenesisRoot
+	}
+	st, err := s.cfg.BeaconDB.GenesisState(ctx)
+	if err != nil {
+		return nil, errors.Wrap(err, "could not get genesis state")
+	}
+	if st.Version() < version.Bellatrix {
+		return nil, nil
+	}
+	header, err := st.LatestExecutionPayloadHeader()
+	if err != nil {
+		return nil, errors.Wrap(err, "could not get latest execution payload header")
+	}
+	return bytesutil.SafeCopyBytes(header.BlockHash()), nil
+}
+
+// DependentRoot wraps the corresponding method in forkchoice
+func (s *Service) DependentRoot(epoch primitives.Epoch) ([32]byte, error) {
+	s.cfg.ForkChoiceStore.RLock()
+	defer s.cfg.ForkChoiceStore.RUnlock()
+	return s.cfg.ForkChoiceStore.DependentRoot(epoch)
+}

beacon-chain/blockchain/chain_info_norace_test.go

@@ -4,14 +4,14 @@ import (
 	"context"
 	"testing"
 
-	testDB "github.com/prysmaticlabs/prysm/v5/beacon-chain/db/testing"
-	doublylinkedtree "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state/stategen"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
-	"github.com/prysmaticlabs/prysm/v5/testing/util"
+	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
+	doublylinkedtree "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/doubly-linked-tree"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state/stategen"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
 )
 
 func TestHeadSlot_DataRace(t *testing.T) {

beacon-chain/blockchain/chain_info_test.go

@@ -5,21 +5,21 @@ import (
 	"testing"
 	"time"
 
-	testDB "github.com/prysmaticlabs/prysm/v5/beacon-chain/db/testing"
-	doublylinkedtree "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/doubly-linked-tree"
-	forkchoicetypes "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/types"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	state_native "github.com/prysmaticlabs/prysm/v5/beacon-chain/state/state-native"
-	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
-	"github.com/prysmaticlabs/prysm/v5/testing/util"
+	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
+	doublylinkedtree "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/doubly-linked-tree"
+	forkchoicetypes "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/types"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	state_native "github.com/OffchainLabs/prysm/v6/beacon-chain/state/state-native"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -613,3 +613,20 @@ func TestService_IsFinalized(t *testing.T) {
 	require.Equal(t, true, c.IsFinalized(ctx, br))
 	require.Equal(t, false, c.IsFinalized(ctx, [32]byte{'c'}))
 }
+
+func Test_hashForGenesisRoot(t *testing.T) {
+	beaconDB := testDB.SetupDB(t)
+	ctx := context.Background()
+	c := setupBeaconChain(t, beaconDB)
+	st, _ := util.DeterministicGenesisStateElectra(t, 10)
+	require.NoError(t, c.cfg.BeaconDB.SaveGenesisData(ctx, st))
+	root, err := beaconDB.GenesisBlockRoot(ctx)
+	require.NoError(t, err)
+	genRoot, err := c.hashForGenesisBlock(ctx, [32]byte{'a'})
+	require.ErrorIs(t, err, errNotGenesisRoot)
+	require.IsNil(t, genRoot)
+
+	genRoot, err = c.hashForGenesisBlock(ctx, root)
+	require.NoError(t, err)
+	require.Equal(t, [32]byte{}, [32]byte(genRoot))
+}

beacon-chain/blockchain/defragment.go

@@ -1,11 +1,11 @@
 package blockchain
 
 import (
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/config/features"
+	"github.com/OffchainLabs/prysm/v6/time"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/v5/config/features"
-	"github.com/prysmaticlabs/prysm/v5/time"
 )
 
 var stateDefragmentationTime = promauto.NewSummary(prometheus.SummaryOpts{

beacon-chain/blockchain/error.go

@@ -1,8 +1,14 @@
 package blockchain
 
-import "github.com/pkg/errors"
+import (
+	stderrors "errors"
+
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
+	"github.com/pkg/errors"
+)
 
 var (
+	// ErrInvalid indicates a verification failure that should result in peer downscoring.
 	// ErrInvalidPayload is returned when the payload is invalid
 	ErrInvalidPayload = invalidBlock{error: errors.New("received an INVALID payload from execution engine")}
 	// ErrInvalidBlockHashPayloadStatus is returned when the payload has invalid block hash.
@@ -30,9 +36,13 @@ var (
 	ErrNotCheckpoint = errors.New("not a checkpoint in forkchoice")
 	// ErrNilHead is returned when no head is present in the blockchain service.
 	ErrNilHead = errors.New("nil head")
+	// errNotGenesisRoot is returned when the root is not the genesis block root.
+	errNotGenesisRoot = errors.New("root is not the genesis block root")
+	// errBlacklistedBlock is returned when a block is blacklisted as invalid.
+	errBlacklistedRoot = verification.AsVerificationFailure(errors.New("block root is blacklisted"))
 )
 
-var errMaxBlobsExceeded = errors.New("Expected commitments in block exceeds MAX_BLOBS_PER_BLOCK")
+var errMaxBlobsExceeded = verification.AsVerificationFailure(errors.New("Expected commitments in block exceeds MAX_BLOBS_PER_BLOCK"))
 
 // An invalid block is the block that fails state transition based on the core protocol rules.
 // The beacon node shall not be accepting nor building blocks that branch off from an invalid block.
@@ -78,6 +88,15 @@ func IsInvalidBlock(e error) bool {
 	return errors.As(e, &d)
 }
 
+// Unwrap ensures that any error using invalidBlock passes an errors.Is check for
+// verification.ErrInvalid.
+func (e invalidBlock) Unwrap() error {
+	if !errors.Is(e.error, verification.ErrInvalid) {
+		return stderrors.Join(e.error, verification.ErrInvalid)
+	}
+	return e.error
+}
+
 // InvalidBlockLVH returns the invalid block last valid hash root. If the error
 // doesn't have a last valid hash, [32]byte{} is returned.
 func InvalidBlockLVH(e error) [32]byte {

beacon-chain/blockchain/error_test.go

@@ -3,8 +3,9 @@ package blockchain
 import (
 	"testing"
 
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/verification"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
 )
 
 func TestIsInvalidBlock(t *testing.T) {
@@ -42,3 +43,8 @@ func TestInvalidRoots(t *testing.T) {
 	require.Equal(t, [32]byte{'a'}, InvalidBlockRoot(newErr))
 	require.DeepEqual(t, roots, InvalidAncestorRoots(newErr))
 }
+
+func TestInvalidRecognition(t *testing.T) {
+	err := invalidBlock{error: errors.New("test"), root: [32]byte{}}
+	require.Equal(t, true, errors.Is(err, verification.ErrInvalid))
+}

beacon-chain/blockchain/execution_engine.go

@@ -4,29 +4,29 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/OffchainLabs/prysm/v6/async/event"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/blocks"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed"
+	statefeed "github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/state"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/time"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/transition"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/execution"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/config/features"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	consensusblocks "github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
+	payloadattribute "github.com/OffchainLabs/prysm/v6/consensus-types/payload-attribute"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	enginev1 "github.com/OffchainLabs/prysm/v6/proto/engine/v1"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/async/event"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/blocks"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed"
-	statefeed "github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed/state"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/time"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/transition"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/execution"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/v5/config/features"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	consensusblocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
-	payloadattribute "github.com/prysmaticlabs/prysm/v5/consensus-types/payload-attribute"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	"github.com/prysmaticlabs/prysm/v5/monitoring/tracing/trace"
-	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	"github.com/prysmaticlabs/prysm/v5/runtime/version"
-	"github.com/prysmaticlabs/prysm/v5/time/slots"
 	"github.com/sirupsen/logrus"
 )
 
@@ -69,6 +69,18 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *fcuConfig) (*
 		SafeBlockHash:      justifiedHash[:],
 		FinalizedBlockHash: finalizedHash[:],
 	}
+	if len(fcs.HeadBlockHash) != 32 || [32]byte(fcs.HeadBlockHash) == [32]byte{} {
+		// check if we are sending FCU at genesis
+		hash, err := s.hashForGenesisBlock(ctx, arg.headRoot)
+		if errors.Is(err, errNotGenesisRoot) {
+			log.Error("Sending nil head block hash to execution engine")
+			return nil, nil
+		}
+		if err != nil {
+			return nil, errors.Wrap(err, "could not get head block hash")
+		}
+		fcs.HeadBlockHash = hash
+	}
 	if arg.attributes == nil {
 		arg.attributes = payloadattribute.EmptyWithVersion(headBlk.Version())
 	}
@@ -172,13 +184,13 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *fcuConfig) (*
 	return payloadID, nil
 }
 
-func firePayloadAttributesEvent(_ context.Context, f event.SubscriberSender, nextSlot primitives.Slot) {
+func firePayloadAttributesEvent(f event.SubscriberSender, block interfaces.ReadOnlySignedBeaconBlock, root [32]byte, nextSlot primitives.Slot) {
 	// the fcu args have differing amounts of completeness based on the code path,
 	// and there is work we only want to do if a client is actually listening to the events beacon api endpoint.
 	// temporary solution: just fire a blank event and fill in the details in the api handler.
 	f.Send(&feed.Event{
 		Type: statefeed.PayloadAttributes,
-		Data: payloadattribute.EventData{ProposalSlot: nextSlot},
+		Data: payloadattribute.EventData{HeadBlock: block, HeadRoot: root, ProposalSlot: nextSlot},
 	})
 }
 

beacon-chain/blockchain/execution_engine_test.go

@@ -5,27 +5,27 @@ import (
 	"testing"
 	"time"
 
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/blocks"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/execution"
+	mockExecution "github.com/OffchainLabs/prysm/v6/beacon-chain/execution/testing"
+	forkchoicetypes "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/types"
+	bstate "github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	state_native "github.com/OffchainLabs/prysm/v6/beacon-chain/state/state-native"
+	"github.com/OffchainLabs/prysm/v6/config/features"
+	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/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"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
 	"github.com/ethereum/go-ethereum/common"
 	gethtypes "github.com/ethereum/go-ethereum/core/types"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/blocks"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/execution"
-	mockExecution "github.com/prysmaticlabs/prysm/v5/beacon-chain/execution/testing"
-	forkchoicetypes "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/types"
-	bstate "github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	state_native "github.com/prysmaticlabs/prysm/v5/beacon-chain/state/state-native"
-	"github.com/prysmaticlabs/prysm/v5/config/features"
-	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	consensusblocks "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/encoding/bytesutil"
-	v1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
-	"github.com/prysmaticlabs/prysm/v5/testing/util"
 )
 
 func Test_NotifyForkchoiceUpdate_GetPayloadAttrErrorCanContinue(t *testing.T) {
@@ -84,7 +84,7 @@ func Test_NotifyForkchoiceUpdate_GetPayloadAttrErrorCanContinue(t *testing.T) {
 	service.cfg.PayloadIDCache.Set(1, [32]byte{}, [8]byte{})
 	got, err := service.notifyForkchoiceUpdate(ctx, arg)
 	require.NoError(t, err)
-	require.DeepEqual(t, got, pid) // We still get a payload ID even though the state is bad. This means it returns until the end.
+	require.IsNil(t, got)
 }
 
 func Test_NotifyForkchoiceUpdate(t *testing.T) {
@@ -113,6 +113,7 @@ func Test_NotifyForkchoiceUpdate(t *testing.T) {
 	state, blkRoot, err = prepareForkchoiceState(ctx, 2, bellatrixBlkRoot, altairBlkRoot, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
 	require.NoError(t, fcs.InsertNode(ctx, state, blkRoot))
+	badHash := [32]byte{'h'}
 
 	tests := []struct {
 		name             string
@@ -210,7 +211,7 @@ func Test_NotifyForkchoiceUpdate(t *testing.T) {
 			blk: func() interfaces.ReadOnlySignedBeaconBlock {
 				b, err := consensusblocks.NewSignedBeaconBlock(&ethpb.SignedBeaconBlockBellatrix{Block: &ethpb.BeaconBlockBellatrix{
 					Body: &ethpb.BeaconBlockBodyBellatrix{
-						ExecutionPayload: &v1.ExecutionPayload{},
+						ExecutionPayload: &v1.ExecutionPayload{BlockHash: badHash[:]},
 					},
 				}})
 				require.NoError(t, err)

beacon-chain/blockchain/forkchoice_update_execution.go

@@ -5,15 +5,15 @@ import (
 	"fmt"
 	"time"
 
+	doublylinkedtree "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/doubly-linked-tree"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
+	payloadattribute "github.com/OffchainLabs/prysm/v6/consensus-types/payload-attribute"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/pkg/errors"
-	doublylinkedtree "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/doubly-linked-tree"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
-	payloadattribute "github.com/prysmaticlabs/prysm/v5/consensus-types/payload-attribute"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/monitoring/tracing/trace"
-	"github.com/prysmaticlabs/prysm/v5/time/slots"
 	"github.com/sirupsen/logrus"
 )
 
@@ -102,12 +102,10 @@ func (s *Service) forkchoiceUpdateWithExecution(ctx context.Context, args *fcuCo
 		log.WithError(err).Error("could not save head")
 	}
 
-	go firePayloadAttributesEvent(ctx, s.cfg.StateNotifier.StateFeed(), s.CurrentSlot()+1)
+	go firePayloadAttributesEvent(s.cfg.StateNotifier.StateFeed(), args.headBlock, args.headRoot, s.CurrentSlot()+1)
 
 	// Only need to prune attestations from pool if the head has changed.
-	if err := s.pruneAttsFromPool(s.ctx, args.headState, args.headBlock); err != nil {
-		log.WithError(err).Error("could not prune attestations from pool")
-	}
+	s.pruneAttsFromPool(s.ctx, args.headState, args.headBlock)
 	return nil
 }
 

beacon-chain/blockchain/forkchoice_update_execution_test.go

@@ -5,15 +5,15 @@ import (
 	"testing"
 	"time"
 
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
-	testDB "github.com/prysmaticlabs/prysm/v5/beacon-chain/db/testing"
-	mockExecution "github.com/prysmaticlabs/prysm/v5/beacon-chain/execution/testing"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
-	"github.com/prysmaticlabs/prysm/v5/testing/util"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
+	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
+	mockExecution "github.com/OffchainLabs/prysm/v6/beacon-chain/execution/testing"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
 	logTest "github.com/sirupsen/logrus/hooks/test"
 )
 

beacon-chain/blockchain/head.go

@@ -5,24 +5,23 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed"
+	statefeed "github.com/OffchainLabs/prysm/v6/beacon-chain/core/feed/state"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/config/features"
+	fieldparams "github.com/OffchainLabs/prysm/v6/config/fieldparams"
+	"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/encoding/bytesutil"
+	"github.com/OffchainLabs/prysm/v6/math"
+	"github.com/OffchainLabs/prysm/v6/monitoring/tracing/trace"
+	ethpbv1 "github.com/OffchainLabs/prysm/v6/proto/eth/v1"
+	"github.com/OffchainLabs/prysm/v6/runtime/version"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed"
-	statefeed "github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed/state"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/v5/config/features"
-	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"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/encoding/bytesutil"
-	"github.com/prysmaticlabs/prysm/v5/math"
-	"github.com/prysmaticlabs/prysm/v5/monitoring/tracing/trace"
-	ethpbv1 "github.com/prysmaticlabs/prysm/v5/proto/eth/v1"
-	"github.com/prysmaticlabs/prysm/v5/runtime/version"
-	"github.com/prysmaticlabs/prysm/v5/time/slots"
 	"github.com/sirupsen/logrus"
 )
 
@@ -328,34 +327,22 @@ func (s *Service) notifyNewHeadEvent(
 	newHeadStateRoot,
 	newHeadRoot []byte,
 ) error {
-	previousDutyDependentRoot := s.originBlockRoot[:]
-	currentDutyDependentRoot := s.originBlockRoot[:]
+	currEpoch := slots.ToEpoch(newHeadSlot)
+	currentDutyDependentRoot, err := s.DependentRoot(currEpoch)
+	if err != nil {
+		return errors.Wrap(err, "could not get duty dependent root")
+	}
+	if currentDutyDependentRoot == [32]byte{} {
+		currentDutyDependentRoot = s.originBlockRoot
+	}
+	previousDutyDependentRoot := currentDutyDependentRoot
+	if currEpoch > 0 {
+		previousDutyDependentRoot, err = s.DependentRoot(currEpoch.Sub(1))
+		if err != nil {
+			return errors.Wrap(err, "could not get duty dependent root")
+		}
+	}
 
-	var previousDutyEpoch primitives.Epoch
-	currentDutyEpoch := slots.ToEpoch(newHeadSlot)
-	if currentDutyEpoch > 0 {
-		previousDutyEpoch = currentDutyEpoch.Sub(1)
-	}
-	currentDutySlot, err := slots.EpochStart(currentDutyEpoch)
-	if err != nil {
-		return errors.Wrap(err, "could not get duty slot")
-	}
-	previousDutySlot, err := slots.EpochStart(previousDutyEpoch)
-	if err != nil {
-		return errors.Wrap(err, "could not get duty slot")
-	}
-	if currentDutySlot > 0 {
-		currentDutyDependentRoot, err = helpers.BlockRootAtSlot(newHeadState, currentDutySlot-1)
-		if err != nil {
-			return errors.Wrap(err, "could not get duty dependent root")
-		}
-	}
-	if previousDutySlot > 0 {
-		previousDutyDependentRoot, err = helpers.BlockRootAtSlot(newHeadState, previousDutySlot-1)
-		if err != nil {
-			return errors.Wrap(err, "could not get duty dependent root")
-		}
-	}
 	isOptimistic, err := s.IsOptimistic(ctx)
 	if err != nil {
 		return errors.Wrap(err, "could not check if node is optimistically synced")
@@ -367,8 +354,8 @@ func (s *Service) notifyNewHeadEvent(
 			Block:                     newHeadRoot,
 			State:                     newHeadStateRoot,
 			EpochTransition:           slots.IsEpochStart(newHeadSlot),
-			PreviousDutyDependentRoot: previousDutyDependentRoot,
-			CurrentDutyDependentRoot:  currentDutyDependentRoot,
+			PreviousDutyDependentRoot: previousDutyDependentRoot[:],
+			CurrentDutyDependentRoot:  currentDutyDependentRoot[:],
 			ExecutionOptimistic:       isOptimistic,
 		},
 	})
@@ -410,7 +397,11 @@ func (s *Service) saveOrphanedOperations(ctx context.Context, orphanedRoot [32]b
 					return err
 				}
 			} else {
-				if a.IsAggregated() {
+				if orphanedBlk.Version() >= version.Electra {
+					if err = s.cfg.AttPool.SaveBlockAttestation(a); err != nil {
+						return err
+					}
+				} else if a.IsAggregated() {
 					if err = s.cfg.AttPool.SaveAggregatedAttestation(a); err != nil {
 						return err
 					}

beacon-chain/blockchain/head_sync_committee_info.go

@@ -4,18 +4,18 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/OffchainLabs/prysm/v6/async"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/altair"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/helpers"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/signing"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/transition"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/state"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/async"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/altair"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/helpers"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/signing"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/transition"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/time/slots"
 )
 
 // Initialize the state cache for sync committees.

beacon-chain/blockchain/head_sync_committee_info_test.go

@@ -4,14 +4,14 @@ import (
 	"context"
 	"testing"
 
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/signing"
-	dbTest "github.com/prysmaticlabs/prysm/v5/beacon-chain/db/testing"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
-	"github.com/prysmaticlabs/prysm/v5/testing/util"
-	"github.com/prysmaticlabs/prysm/v5/time/slots"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/cache"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/core/signing"
+	dbTest "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 )
 
 func TestService_HeadSyncCommitteeIndices(t *testing.T) {

beacon-chain/blockchain/head_test.go

@@ -7,20 +7,21 @@ import (
 	"testing"
 	"time"
 
-	mock "github.com/prysmaticlabs/prysm/v5/beacon-chain/blockchain/testing"
-	testDB "github.com/prysmaticlabs/prysm/v5/beacon-chain/db/testing"
-	forkchoicetypes "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/types"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/operations/blstoexec"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	ethpbv1 "github.com/prysmaticlabs/prysm/v5/proto/eth/v1"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
-	"github.com/prysmaticlabs/prysm/v5/testing/util"
-	"github.com/prysmaticlabs/prysm/v5/time/slots"
+	mock "github.com/OffchainLabs/prysm/v6/beacon-chain/blockchain/testing"
+	testDB "github.com/OffchainLabs/prysm/v6/beacon-chain/db/testing"
+	doublylinkedtree "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/doubly-linked-tree"
+	forkchoicetypes "github.com/OffchainLabs/prysm/v6/beacon-chain/forkchoice/types"
+	"github.com/OffchainLabs/prysm/v6/beacon-chain/operations/blstoexec"
+	"github.com/OffchainLabs/prysm/v6/config/params"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v6/encoding/bytesutil"
+	ethpbv1 "github.com/OffchainLabs/prysm/v6/proto/eth/v1"
+	ethpb "github.com/OffchainLabs/prysm/v6/proto/prysm/v1alpha1"
+	"github.com/OffchainLabs/prysm/v6/testing/assert"
+	"github.com/OffchainLabs/prysm/v6/testing/require"
+	"github.com/OffchainLabs/prysm/v6/testing/util"
+	"github.com/OffchainLabs/prysm/v6/time/slots"
 	logTest "github.com/sirupsen/logrus/hooks/test"
 )
 
@@ -156,14 +157,17 @@ func Test_notifyNewHeadEvent(t *testing.T) {
 		notifier := &mock.MockStateNotifier{RecordEvents: true}
 		srv := &Service{
 			cfg: &config{
-				StateNotifier: notifier,
+				StateNotifier:   notifier,
+				ForkChoiceStore: doublylinkedtree.New(),
 			},
 			originBlockRoot: [32]byte{1},
 		}
+		st, blk, err := prepareForkchoiceState(context.Background(), 0, [32]byte{}, [32]byte{}, [32]byte{}, &ethpb.Checkpoint{}, &ethpb.Checkpoint{})
+		require.NoError(t, err)
+		require.NoError(t, srv.cfg.ForkChoiceStore.InsertNode(context.Background(), st, blk))
 		newHeadStateRoot := [32]byte{2}
 		newHeadRoot := [32]byte{3}
-		err := srv.notifyNewHeadEvent(context.Background(), 1, bState, newHeadStateRoot[:], newHeadRoot[:])
-		require.NoError(t, err)
+		require.NoError(t, srv.notifyNewHeadEvent(context.Background(), 1, bState, newHeadStateRoot[:], newHeadRoot[:]))
 		events := notifier.ReceivedEvents()
 		require.Equal(t, 1, len(events))
 
@@ -185,10 +189,14 @@ func Test_notifyNewHeadEvent(t *testing.T) {
 		genesisRoot := [32]byte{1}
 		srv := &Service{
 			cfg: &config{
-				StateNotifier: notifier,
+				StateNotifier:   notifier,
+				ForkChoiceStore: doublylinkedtree.New(),
 			},
 			originBlockRoot: genesisRoot,
 		}
+		st, blk, err := prepareForkchoiceState(context.Background(), 0, [32]byte{}, [32]byte{}, [32]byte{}, &ethpb.Checkpoint{}, &ethpb.Checkpoint{})
+		require.NoError(t, err)
+		require.NoError(t, srv.cfg.ForkChoiceStore.InsertNode(context.Background(), st, blk))
 		epoch1Start, err := slots.EpochStart(1)
 		require.NoError(t, err)
 		epoch2Start, err := slots.EpochStart(1)
@@ -209,8 +217,8 @@ func Test_notifyNewHeadEvent(t *testing.T) {
 			Block:                     newHeadRoot[:],
 			State:                     newHeadStateRoot[:],
 			EpochTransition:           true,
-			PreviousDutyDependentRoot: genesisRoot[:],
-			CurrentDutyDependentRoot:  make([]byte, 32),
+			PreviousDutyDependentRoot: make([]byte, 32),
+			CurrentDutyDependentRoot:  srv.originBlockRoot[:],
 		}
 		require.DeepSSZEqual(t, wanted, eventHead)
 	})
@@ -324,6 +332,72 @@ func TestSaveOrphanedAtts(t *testing.T) {
 	require.DeepEqual(t, wantAtts, atts)
 }
 
+func TestSaveOrphanedAttsElectra(t *testing.T) {
+	ctx := context.Background()
+	beaconDB := testDB.SetupDB(t)
+	service := setupBeaconChain(t, beaconDB)
+	service.genesisTime = time.Now().Add(time.Duration(-10*int64(1)*int64(params.BeaconConfig().SecondsPerSlot)) * time.Second)
+
+	// Chain setup
+	// 0 -- 1 -- 2 -- 3
+	//  \-4
+	st, keys := util.DeterministicGenesisStateElectra(t, 64)
+	blkG, err := util.GenerateFullBlockElectra(st, keys, util.DefaultBlockGenConfig(), 1)
+	assert.NoError(t, err)
+
+	util.SaveBlock(t, ctx, service.cfg.BeaconDB, blkG)
+	rG, err := blkG.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	blk1, err := util.GenerateFullBlockElectra(st, keys, util.DefaultBlockGenConfig(), 2)
+	assert.NoError(t, err)
+	blk1.Block.ParentRoot = rG[:]
+	r1, err := blk1.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	blk2, err := util.GenerateFullBlockElectra(st, keys, util.DefaultBlockGenConfig(), 3)
+	assert.NoError(t, err)
+	blk2.Block.ParentRoot = r1[:]
+	r2, err := blk2.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	blk3, err := util.GenerateFullBlockElectra(st, keys, util.DefaultBlockGenConfig(), 4)
+	assert.NoError(t, err)
+	blk3.Block.ParentRoot = r2[:]
+	r3, err := blk3.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	blk4 := util.NewBeaconBlockElectra()
+	blk4.Block.Slot = 4
+	blk4.Block.ParentRoot = rG[:]
+	r4, err := blk4.Block.HashTreeRoot()
+	require.NoError(t, err)
+	ojc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
+	ofc := &ethpb.Checkpoint{Root: params.BeaconConfig().ZeroHash[:]}
+
+	for _, blk := range []*ethpb.SignedBeaconBlockElectra{blkG, blk1, blk2, blk3, blk4} {
+		r, err := blk.Block.HashTreeRoot()
+		require.NoError(t, err)
+		state, blkRoot, err := prepareForkchoiceState(ctx, blk.Block.Slot, r, bytesutil.ToBytes32(blk.Block.ParentRoot), [32]byte{}, ojc, ofc)
+		require.NoError(t, err)
+		require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
+		util.SaveBlock(t, ctx, beaconDB, blk)
+	}
+
+	require.NoError(t, service.saveOrphanedOperations(ctx, r3, r4))
+	require.Equal(t, 3, len(service.cfg.AttPool.BlockAttestations()))
+	wantAtts := []ethpb.Att{
+		blk3.Block.Body.Attestations[0],
+		blk2.Block.Body.Attestations[0],
+		blk1.Block.Body.Attestations[0],
+	}
+	atts := service.cfg.AttPool.BlockAttestations()
+	sort.Slice(atts, func(i, j int) bool {
+		return atts[i].GetData().Slot > atts[j].GetData().Slot
+	})
+	require.DeepEqual(t, wantAtts, atts)
+}
+
 func TestSaveOrphanedOps(t *testing.T) {
 	params.SetupTestConfigCleanup(t)
 	config := params.BeaconConfig()

beacon-chain/blockchain/init_sync_process_block.go

@@ -3,9 +3,9 @@ package blockchain
 import (
 	"context"
 
+	"github.com/OffchainLabs/prysm/v6/consensus-types/blocks"
+	"github.com/OffchainLabs/prysm/v6/consensus-types/interfaces"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
 )
 
 // This saves a beacon block to the initial sync blocks cache. It rate limits how many blocks