Remove inclusion list from epbs (#14188 )

Enable validator client to submit payload attestation message (#14064 )
Add PTC assignment support for Duty endpoint (#14032 )
2026-01-10 05:47:59 -05:00 · 2024-07-15 13:20:12 -03:00 · 2024-07-15 13:20:06 -03:00 · 2024-07-15 13:14:41 -03:00 · 2024-07-15 13:13:46 -03:00 · 2024-07-15 13:13:46 -03:00
1330 changed files with 96467 additions and 55492 deletions
--- a/.bazelrc
+++ b/.bazelrc
@@ -6,6 +6,12 @@ import %workspace%/build/bazelrc/debug.bazelrc
 import %workspace%/build/bazelrc/hermetic-cc.bazelrc
 import %workspace%/build/bazelrc/performance.bazelrc

+# hermetic_cc_toolchain v3.0.1 required changes.
+common --enable_platform_specific_config
+build:linux --sandbox_add_mount_pair=/tmp
+build:macos --sandbox_add_mount_pair=/var/tmp
+build:windows --sandbox_add_mount_pair=C:\Temp
+
 # E2E run with debug gotag
 test:e2e --define gotags=debug

--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-7.0.0
+7.1.0
--- a/.buildkite-bazelrc
+++ b/.buildkite-bazelrc
@@ -12,8 +12,7 @@
 build:remote-cache --remote_download_minimal
 build:remote-cache --remote_build_event_upload=minimal
 build:remote-cache --remote_cache=grpc://bazel-remote-cache:9092
-# Does not work with rules_oci. See https://github.com/bazel-contrib/rules_oci/issues/292
-#build:remote-cache --experimental_remote_downloader=grpc://bazel-remote-cache:9092
+build:remote-cache --experimental_remote_downloader=grpc://bazel-remote-cache:9092
 build:remote-cache --remote_local_fallback
 build:remote-cache --experimental_remote_cache_async
 build:remote-cache --experimental_remote_merkle_tree_cache
--- a/.github/actions/gomodtidy/Dockerfile
+++ b/.github/actions/gomodtidy/Dockerfile
@@ -1,4 +1,4 @@
-FROM golang:1.21-alpine
+FROM golang:1.22-alpine

 COPY entrypoint.sh /entrypoint.sh

--- a/.github/workflows/fuzz.yml
+++ b/.github/workflows/fuzz.yml
@@ -16,7 +16,7 @@ jobs:
      - uses: actions/checkout@v3
      - uses: actions/setup-go@v4
        with:
-          go-version: '1.21.5'
+          go-version: '1.22.3'
      - id: list
        uses: shogo82148/actions-go-fuzz/list@v0
        with:
@@ -36,7 +36,7 @@ jobs:
      - uses: actions/checkout@v3
      - uses: actions/setup-go@v4
        with:
-          go-version: '1.21.5'
+          go-version: '1.22.3'
      - uses: shogo82148/actions-go-fuzz/run@v0
        with:
          packages: ${{ matrix.package }}
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -28,14 +28,14 @@ jobs:
    steps:
      - name: Checkout
        uses: actions/checkout@v2
-      - name: Set up Go 1.21
+      - name: Set up Go 1.22
        uses: actions/setup-go@v3
        with:
-          go-version: '1.21.5'
+          go-version: '1.22.3'
      - name: Run Gosec Security Scanner
        run: | # https://github.com/securego/gosec/issues/469
          export PATH=$PATH:$(go env GOPATH)/bin
-          go install github.com/securego/gosec/v2/cmd/gosec@v2.15.0
+          go install github.com/securego/gosec/v2/cmd/gosec@v2.19.0
          gosec -exclude-generated -exclude=G307 -exclude-dir=crypto/bls/herumi ./...

  lint:
@@ -45,10 +45,10 @@ jobs:
      - name: Checkout
        uses: actions/checkout@v2

-      - name: Set up Go 1.21
+      - name: Set up Go 1.22
        uses: actions/setup-go@v3
        with:
-          go-version: '1.21.5'
+          go-version: '1.22.3'
          id: go

      - name: Golangci-lint
@@ -64,7 +64,7 @@ jobs:
      - name: Set up Go 1.x
        uses: actions/setup-go@v2
        with:
-          go-version: '1.21.5'
+          go-version: '1.22.3'
        id: go

      - name: Check out code into the Go module directory
--- a/.gitignore
+++ b/.gitignore
@@ -41,3 +41,6 @@ jwt.hex

 # manual testing
 tmp
+
+# spectest coverage reports
+report.txt
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -6,7 +6,7 @@ run:
    - proto
    - tools/analyzers
  timeout: 10m
-  go: '1.21.5'
+  go: '1.22.3'

 linters:
  enable-all: true
@@ -34,7 +34,6 @@ linters:
    - dogsled
    - dupl
    - durationcheck
-    - errorlint
    - exhaustive
    - exhaustruct
    - forbidigo
@@ -52,6 +51,7 @@ linters:
    - gofumpt
    - gomnd
    - gomoddirectives
+    - gosec
    - inamedparam
    - interfacebloat
    - ireturn
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -224,6 +224,7 @@ nogo(
        "@org_golang_x_tools//go/analysis/passes/deepequalerrors:go_default_library",
        "@org_golang_x_tools//go/analysis/passes/defers:go_default_library",
        "@org_golang_x_tools//go/analysis/passes/directive:go_default_library",
+        "@org_golang_x_tools//go/analysis/passes/errorsas:go_default_library",
        # fieldalignment disabled
        #"@org_golang_x_tools//go/analysis/passes/fieldalignment:go_default_library",
        "@org_golang_x_tools//go/analysis/passes/findcall:go_default_library",
--- a/MODULE.bazel.lock
+++ b/MODULE.bazel.lock
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@

 [![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)
-[![Consensus_Spec_Version 1.3.0](https://img.shields.io/badge/Consensus%20Spec%20Version-v1.3.0-blue.svg)](https://github.com/ethereum/consensus-specs/tree/v1.3.0)
+[![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)
--- a/96
+++ b/96
@@ -16,34 +16,20 @@ load("@rules_pkg//:deps.bzl", "rules_pkg_dependencies")

 rules_pkg_dependencies()

+HERMETIC_CC_TOOLCHAIN_VERSION = "v3.0.1"
+
 http_archive(
    name = "hermetic_cc_toolchain",
-    sha256 = "973ab22945b921ef45b8e1d6ce01ca7ce1b8a462167449a36e297438c4ec2755",
-    strip_prefix = "hermetic_cc_toolchain-5098046bccc15d2962f3cc8e7e53d6a2a26072dc",
+    sha256 = "3bc6ec127622fdceb4129cb06b6f7ab098c4d539124dde96a6318e7c32a53f7a",
    urls = [
-        "https://github.com/uber/hermetic_cc_toolchain/archive/5098046bccc15d2962f3cc8e7e53d6a2a26072dc.tar.gz",  # 2023-06-28
+        "https://mirror.bazel.build/github.com/uber/hermetic_cc_toolchain/releases/download/{0}/hermetic_cc_toolchain-{0}.tar.gz".format(HERMETIC_CC_TOOLCHAIN_VERSION),
+        "https://github.com/uber/hermetic_cc_toolchain/releases/download/{0}/hermetic_cc_toolchain-{0}.tar.gz".format(HERMETIC_CC_TOOLCHAIN_VERSION),
    ],
 )

 load("@hermetic_cc_toolchain//toolchain:defs.bzl", zig_toolchains = "toolchains")

-# Temporarily use a nightly build until 0.12.0 is released.
-# See: https://github.com/prysmaticlabs/prysm/issues/13130
-zig_toolchains(
-    host_platform_sha256 = {
-        "linux-aarch64": "45afb8e32adde825165f4f293fcea9ecea503f7f9ec0e9bf4435afe70e67fb70",
-        "linux-x86_64": "f136c6a8a0f6adcb057d73615fbcd6f88281b3593f7008d5f7ed514ff925c02e",
-        "macos-aarch64": "05d995853c05243151deff47b60bdc2674f1e794a939eaeca0f42312da031cee",
-        "macos-x86_64": "721754ba5a50f31e8a1f0e1a74cace26f8246576878ac4a8591b0ee7b6db1fc1",
-        "windows-x86_64": "93f5248b2ea8c5ee8175e15b1384e133edc1cd49870b3ea259062a2e04164343",
-    },
-    url_formats = [
-        "https://ziglang.org/builds/zig-{host_platform}-{version}.{_ext}",
-        "https://mirror.bazel.build/ziglang.org/builds/zig-{host_platform}-{version}.{_ext}",
-        "https://prysmaticlabs.com/mirror/ziglang.org/builds/zig-{host_platform}-{version}.{_ext}",
-    ],
-    version = "0.12.0-dev.1349+fa022d1ec",
-)
+zig_toolchains()

 # Register zig sdk toolchains with support for Ubuntu 20.04 (Focal Fossa) which has an EOL date of April, 2025.
 # For ubuntu glibc support, see https://launchpad.net/ubuntu/+source/glibc
@@ -81,10 +67,10 @@ bazel_skylib_workspace()

 http_archive(
    name = "bazel_gazelle",
-    sha256 = "d3fa66a39028e97d76f9e2db8f1b0c11c099e8e01bf363a923074784e451f809",
+    integrity = "sha256-MpOL2hbmcABjA1R5Bj2dJMYO2o15/Uc5Vj9Q0zHLMgk=",
    urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/bazel-gazelle/releases/download/v0.33.0/bazel-gazelle-v0.33.0.tar.gz",
-        "https://github.com/bazelbuild/bazel-gazelle/releases/download/v0.33.0/bazel-gazelle-v0.33.0.tar.gz",
+        "https://mirror.bazel.build/github.com/bazelbuild/bazel-gazelle/releases/download/v0.35.0/bazel-gazelle-v0.35.0.tar.gz",
+        "https://github.com/bazelbuild/bazel-gazelle/releases/download/v0.35.0/bazel-gazelle-v0.35.0.tar.gz",
    ],
 )

@@ -128,9 +114,9 @@ aspect_bazel_lib_register_toolchains()

 http_archive(
    name = "rules_oci",
-    sha256 = "c71c25ed333a4909d2dd77e0b16c39e9912525a98c7fa85144282be8d04ef54c",
-    strip_prefix = "rules_oci-1.3.4",
-    url = "https://github.com/bazel-contrib/rules_oci/releases/download/v1.3.4/rules_oci-v1.3.4.tar.gz",
+    sha256 = "4a276e9566c03491649eef63f27c2816cc222f41ccdebd97d2c5159e84917c3b",
+    strip_prefix = "rules_oci-1.7.4",
+    url = "https://github.com/bazel-contrib/rules_oci/releases/download/v1.7.4/rules_oci-v1.7.4.tar.gz",
 )

 load("@rules_oci//oci:dependencies.bzl", "rules_oci_dependencies")
@@ -151,17 +137,13 @@ http_archive(
        # Expose internals of go_test for custom build transitions.
        "//third_party:io_bazel_rules_go_test.patch",
    ],
-    sha256 = "d6ab6b57e48c09523e93050f13698f708428cfd5e619252e369d377af6597707",
+    sha256 = "80a98277ad1311dacd837f9b16db62887702e9f1d1c4c9f796d0121a46c8e184",
    urls = [
-        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.43.0/rules_go-v0.43.0.zip",
-        "https://github.com/bazelbuild/rules_go/releases/download/v0.43.0/rules_go-v0.43.0.zip",
+        "https://mirror.bazel.build/github.com/bazelbuild/rules_go/releases/download/v0.46.0/rules_go-v0.46.0.zip",
+        "https://github.com/bazelbuild/rules_go/releases/download/v0.46.0/rules_go-v0.46.0.zip",
    ],
 )

-load("//:distroless_deps.bzl", "distroless_deps")
-
-distroless_deps()
-
 # Override default import in rules_go with special patch until
 # https://github.com/gogo/protobuf/pull/582 is merged.
 git_repository(
@@ -200,10 +182,14 @@ load("@io_bazel_rules_go//go:deps.bzl", "go_register_toolchains", "go_rules_depe
 go_rules_dependencies()

 go_register_toolchains(
-    go_version = "1.21.6",
+    go_version = "1.22.4",
    nogo = "@//:nogo",
 )

+load("//:distroless_deps.bzl", "distroless_deps")
+
+distroless_deps()
+
 http_archive(
    name = "io_kubernetes_build",
    sha256 = "b84fbd1173acee9d02a7d3698ad269fdf4f7aa081e9cecd40e012ad0ad8cfa2a",
@@ -241,9 +227,7 @@ filegroup(
    url = "https://github.com/ethereum/EIPs/archive/5480440fe51742ed23342b68cf106cefd427e39d.tar.gz",
 )

-consensus_spec_version = "v1.4.0-beta.7"
-
-consensus_spec_test_version = "v1.4.0-beta.7-hotfix"
+consensus_spec_version = "v1.5.0-alpha.3"

 bls_test_version = "v0.1.1"

@@ -259,8 +243,8 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    sha256 = "c282c0f86f23f3d2e0f71f5975769a4077e62a7e3c7382a16bd26a7e589811a0",
-    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/general.tar.gz" % consensus_spec_test_version,
+    integrity = "sha256-+byv+GUOQytex5GgtjBGVoNDseJZbiBdAjEtlgCbjEo=",
+    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/general.tar.gz" % consensus_spec_version,
 )

 http_archive(
@@ -275,8 +259,8 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    sha256 = "4649c35aa3b8eb0cfdc81bee7c05649f90ef36bede5b0513e1f2e8baf37d6033",
-    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/minimal.tar.gz" % consensus_spec_test_version,
+    integrity = "sha256-JJUy/jT1h3kGQkinTuzL7gMOA1+qgmPgJXVrYuH63Cg=",
+    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/minimal.tar.gz" % consensus_spec_version,
 )

 http_archive(
@@ -291,8 +275,8 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    sha256 = "c5a03f724f757456ffaabd2a899992a71d2baf45ee4db65ca3518f2b7ee928c8",
-    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/mainnet.tar.gz" % consensus_spec_test_version,
+    integrity = "sha256-T2VM4Qd0SwgGnTjWxjOX297DqEsovO9Ueij1UEJy48Y=",
+    url = "https://github.com/ethereum/consensus-spec-tests/releases/download/%s/mainnet.tar.gz" % consensus_spec_version,
 )

 http_archive(
@@ -306,7 +290,7 @@ filegroup(
    visibility = ["//visibility:public"],
 )
    """,
-    sha256 = "049c29267310e6b88280f4f834a75866c2f5b9036fa97acb9d9c6db8f64d9118",
+    integrity = "sha256-OP9BCBcQ7i+93bwj7ktY8pZ5uWsGjgTe4XTp7BDhX+I=",
    strip_prefix = "consensus-specs-" + consensus_spec_version[1:],
    url = "https://github.com/ethereum/consensus-specs/archive/refs/tags/%s.tar.gz" % consensus_spec_version,
 )
@@ -342,36 +326,20 @@ filegroup(
    url = "https://github.com/eth-clients/eth2-networks/archive/934c948e69205dcf2deb87e4ae6cc140c335f94d.tar.gz",
 )

-http_archive(
-    name = "goerli_testnet",
-    build_file_content = """
-filegroup(
-    name = "configs",
-    srcs = [
-        "prater/config.yaml",
-    ],
-    visibility = ["//visibility:public"],
-)
-    """,
-    sha256 = "43fc0f55ddff7b511713e2de07aa22846a67432df997296fb4fc09cd8ed1dcdb",
-    strip_prefix = "goerli-6522ac6684693740cd4ddcc2a0662e03702aa4a1",
-    url = "https://github.com/eth-clients/goerli/archive/6522ac6684693740cd4ddcc2a0662e03702aa4a1.tar.gz",
-)
-
 http_archive(
    name = "holesky_testnet",
    build_file_content = """
 filegroup(
    name = "configs",
    srcs = [
-        "custom_config_data/config.yaml",
+        "metadata/config.yaml",
    ],
    visibility = ["//visibility:public"],
 )
 """,
-    sha256 = "5f4be6fd088683ea9db45c863b9c5a1884422449e5b59fd2d561d3ba0f73ffd9",
-    strip_prefix = "holesky-9d9aabf2d4de51334ee5fed6c79a4d55097d1a43",
-    url = "https://github.com/eth-clients/holesky/archive/9d9aabf2d4de51334ee5fed6c79a4d55097d1a43.tar.gz",  # 2024-01-22
+    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
 )

 http_archive(
--- a/api/BUILD.bazel
+++ b/api/BUILD.bazel
@@ -1,11 +1,24 @@
-load("@prysm//tools/go:def.bzl", "go_library")
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")

 go_library(
    name = "go_default_library",
    srcs = [
        "constants.go",
        "headers.go",
+        "jwt.go",
    ],
    importpath = "github.com/prysmaticlabs/prysm/v5/api",
    visibility = ["//visibility:public"],
+    deps = [
+        "//crypto/rand:go_default_library",
+        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["jwt_test.go"],
+    embed = [":go_default_library"],
+    deps = ["//testing/require:go_default_library"],
 )
--- a/api/client/beacon/BUILD.bazel
+++ b/api/client/beacon/BUILD.bazel
@@ -6,11 +6,14 @@ go_library(
        "checkpoint.go",
        "client.go",
        "doc.go",
+        "health.go",
+        "log.go",
    ],
    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/beacon",
    visibility = ["//visibility:public"],
    deps = [
        "//api/client:go_default_library",
+        "//api/client/beacon/iface:go_default_library",
        "//api/server:go_default_library",
        "//api/server/structs:go_default_library",
        "//beacon-chain/core/helpers:go_default_library",
@@ -36,10 +39,12 @@ go_test(
    srcs = [
        "checkpoint_test.go",
        "client_test.go",
+        "health_test.go",
    ],
    embed = [":go_default_library"],
    deps = [
        "//api/client:go_default_library",
+        "//api/client/beacon/testing:go_default_library",
        "//beacon-chain/state:go_default_library",
        "//config/params:go_default_library",
        "//consensus-types/blocks:go_default_library",
@@ -53,5 +58,6 @@ go_test(
        "//testing/util:go_default_library",
        "//time/slots:go_default_library",
        "@com_github_pkg_errors//:go_default_library",
+        "@org_uber_go_mock//gomock:go_default_library",
    ],
 )
--- a/api/client/beacon/checkpoint.go
+++ b/api/client/beacon/checkpoint.go
@@ -17,7 +17,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/io/file"
 	"github.com/prysmaticlabs/prysm/v5/runtime/version"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
-	log "github.com/sirupsen/logrus"
+	"github.com/sirupsen/logrus"
 	"golang.org/x/mod/semver"
 )

@@ -74,7 +74,12 @@ func DownloadFinalizedData(ctx context.Context, client *Client) (*OriginData, er
 	if err != nil {
 		return nil, errors.Wrap(err, "error detecting chain config for finalized state")
 	}
-	log.Printf("detected supported config in remote finalized state, name=%s, fork=%s", vu.Config.ConfigName, version.String(vu.Fork))
+
+	log.WithFields(logrus.Fields{
+		"name": vu.Config.ConfigName,
+		"fork": version.String(vu.Fork),
+	}).Info("Detected supported config in remote finalized state")
+
 	s, err := vu.UnmarshalBeaconState(sb)
 	if err != nil {
 		return nil, errors.Wrap(err, "error unmarshaling finalized state to correct version")
--- a/api/client/beacon/checkpoint_test.go
+++ b/api/client/beacon/checkpoint_test.go
@@ -9,22 +9,20 @@ import (
 	"net/http"
 	"testing"

+	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/api/client"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
+	"github.com/prysmaticlabs/prysm/v5/config/params"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	blocktest "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks/testing"
-	"github.com/prysmaticlabs/prysm/v5/network/forks"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/prysmaticlabs/prysm/v5/testing/util"
-	"github.com/prysmaticlabs/prysm/v5/time/slots"
-
-	"github.com/prysmaticlabs/prysm/v5/config/params"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v5/encoding/ssz/detect"
+	"github.com/prysmaticlabs/prysm/v5/network/forks"
+	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/runtime/version"
-
-	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	"github.com/prysmaticlabs/prysm/v5/testing/util"
+	"github.com/prysmaticlabs/prysm/v5/time/slots"
 )

 type testRT struct {
--- a/api/client/beacon/client.go
+++ b/api/client/beacon/client.go
@@ -22,7 +22,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/v5/network/forks"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	log "github.com/sirupsen/logrus"
+	"github.com/sirupsen/logrus"
 )

 const (
@@ -309,7 +309,7 @@ func (c *Client) SubmitChangeBLStoExecution(ctx context.Context, request []*stru
 		}
 		for _, failure := range errorJson.Failures {
 			w := request[failure.Index].Message
-			log.WithFields(log.Fields{
+			log.WithFields(logrus.Fields{
 				"validatorIndex":    w.ValidatorIndex,
 				"withdrawalAddress": w.ToExecutionAddress,
 			}).Error(failure.Message)
@@ -341,9 +341,9 @@ type forkScheduleResponse struct {
 func (fsr *forkScheduleResponse) OrderedForkSchedule() (forks.OrderedSchedule, error) {
 	ofs := make(forks.OrderedSchedule, 0)
 	for _, d := range fsr.Data {
-		epoch, err := strconv.Atoi(d.Epoch)
+		epoch, err := strconv.ParseUint(d.Epoch, 10, 64)
 		if err != nil {
-			return nil, err
+			return nil, errors.Wrapf(err, "error parsing epoch %s", d.Epoch)
 		}
 		vSlice, err := hexutil.Decode(d.CurrentVersion)
 		if err != nil {
@@ -355,7 +355,7 @@ func (fsr *forkScheduleResponse) OrderedForkSchedule() (forks.OrderedSchedule, e
 		version := bytesutil.ToBytes4(vSlice)
 		ofs = append(ofs, forks.ForkScheduleEntry{
 			Version: version,
-			Epoch:   primitives.Epoch(uint64(epoch)),
+			Epoch:   primitives.Epoch(epoch),
 		})
 	}
 	sort.Sort(ofs)
--- a/api/client/beacon/health.go
+++ b/api/client/beacon/health.go
@@ -0,0 +1,60 @@
+package beacon
+
+import (
+	"context"
+	"sync"
+
+	"github.com/prysmaticlabs/prysm/v5/api/client/beacon/iface"
+)
+
+type NodeHealthTracker struct {
+	isHealthy  *bool
+	healthChan chan bool
+	node       iface.HealthNode
+	sync.RWMutex
+}
+
+func NewNodeHealthTracker(node iface.HealthNode) *NodeHealthTracker {
+	return &NodeHealthTracker{
+		node:       node,
+		healthChan: make(chan bool, 1),
+	}
+}
+
+// HealthUpdates provides a read-only channel for health updates.
+func (n *NodeHealthTracker) HealthUpdates() <-chan bool {
+	return n.healthChan
+}
+
+func (n *NodeHealthTracker) IsHealthy() bool {
+	n.RLock()
+	defer n.RUnlock()
+	if n.isHealthy == nil {
+		return false
+	}
+	return *n.isHealthy
+}
+
+func (n *NodeHealthTracker) CheckHealth(ctx context.Context) bool {
+	n.Lock()
+	defer n.Unlock()
+
+	newStatus := n.node.IsHealthy(ctx)
+	if n.isHealthy == nil {
+		n.isHealthy = &newStatus
+	}
+
+	isStatusChanged := newStatus != *n.isHealthy
+	if isStatusChanged {
+		// Update the health status
+		n.isHealthy = &newStatus
+		// Send the new status to the health channel, potentially overwriting the existing value
+		select {
+		case <-n.healthChan:
+			n.healthChan <- newStatus
+		default:
+			n.healthChan <- newStatus
+		}
+	}
+	return newStatus
+}
--- a/api/client/beacon/health_test.go
+++ b/api/client/beacon/health_test.go
@@ -0,0 +1,112 @@
+package beacon
+
+import (
+	"context"
+	"sync"
+	"testing"
+
+	healthTesting "github.com/prysmaticlabs/prysm/v5/api/client/beacon/testing"
+	"go.uber.org/mock/gomock"
+)
+
+func TestNodeHealth_IsHealthy(t *testing.T) {
+	tests := []struct {
+		name      string
+		isHealthy bool
+		want      bool
+	}{
+		{"initially healthy", true, true},
+		{"initially unhealthy", false, false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			n := &NodeHealthTracker{
+				isHealthy:  &tt.isHealthy,
+				healthChan: make(chan bool, 1),
+			}
+			if got := n.IsHealthy(); got != tt.want {
+				t.Errorf("IsHealthy() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestNodeHealth_UpdateNodeHealth(t *testing.T) {
+	tests := []struct {
+		name       string
+		initial    bool // Initial health status
+		newStatus  bool // Status to update to
+		shouldSend bool // Should a message be sent through the channel
+	}{
+		{"healthy to unhealthy", true, false, true},
+		{"unhealthy to healthy", false, true, true},
+		{"remain healthy", true, true, false},
+		{"remain unhealthy", false, false, false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctrl := gomock.NewController(t)
+			defer ctrl.Finish()
+			client := healthTesting.NewMockHealthClient(ctrl)
+			client.EXPECT().IsHealthy(gomock.Any()).Return(tt.newStatus)
+			n := &NodeHealthTracker{
+				isHealthy:  &tt.initial,
+				node:       client,
+				healthChan: make(chan bool, 1),
+			}
+
+			s := n.CheckHealth(context.Background())
+			// Check if health status was updated
+			if s != tt.newStatus {
+				t.Errorf("UpdateNodeHealth() failed to update isHealthy from %v to %v", tt.initial, tt.newStatus)
+			}
+
+			select {
+			case status := <-n.HealthUpdates():
+				if !tt.shouldSend {
+					t.Errorf("UpdateNodeHealth() unexpectedly sent status %v to HealthCh", status)
+				} else if status != tt.newStatus {
+					t.Errorf("UpdateNodeHealth() sent wrong status %v, want %v", status, tt.newStatus)
+				}
+			default:
+				if tt.shouldSend {
+					t.Error("UpdateNodeHealth() did not send any status to HealthCh when expected")
+				}
+			}
+		})
+	}
+}
+
+func TestNodeHealth_Concurrency(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+	client := healthTesting.NewMockHealthClient(ctrl)
+	n := NewNodeHealthTracker(client)
+	var wg sync.WaitGroup
+
+	// Number of goroutines to spawn for both reading and writing
+	numGoroutines := 6
+
+	wg.Add(numGoroutines * 2) // for readers and writers
+
+	// Concurrently update health status
+	for i := 0; i < numGoroutines; i++ {
+		go func() {
+			defer wg.Done()
+			client.EXPECT().IsHealthy(gomock.Any()).Return(false).Times(1)
+			n.CheckHealth(context.Background())
+			client.EXPECT().IsHealthy(gomock.Any()).Return(true).Times(1)
+			n.CheckHealth(context.Background())
+		}()
+	}
+
+	// Concurrently read health status
+	for i := 0; i < numGoroutines; i++ {
+		go func() {
+			defer wg.Done()
+			_ = n.IsHealthy() // Just read the value
+		}()
+	}
+
+	wg.Wait() // Wait for all goroutines to finish
+}
--- a/api/client/beacon/iface/BUILD.bazel
+++ b/api/client/beacon/iface/BUILD.bazel
@@ -0,0 +1,8 @@
+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"],
+)
--- a/api/client/beacon/iface/health.go
+++ b/api/client/beacon/iface/health.go
@@ -0,0 +1,13 @@
+package iface
+
+import "context"
+
+type HealthTracker interface {
+	HealthUpdates() <-chan bool
+	IsHealthy() bool
+	CheckHealth(ctx context.Context) bool
+}
+
+type HealthNode interface {
+	IsHealthy(ctx context.Context) bool
+}
--- a/api/client/beacon/log.go
+++ b/api/client/beacon/log.go
@@ -0,0 +1,5 @@
+package beacon
+
+import "github.com/sirupsen/logrus"
+
+var log = logrus.WithField("prefix", "beacon")
--- a/api/client/beacon/testing/BUILD.bazel
+++ b/api/client/beacon/testing/BUILD.bazel
@@ -0,0 +1,12 @@
+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",
+    ],
+)
--- a/api/client/beacon/testing/mock.go
+++ b/api/client/beacon/testing/mock.go
@@ -0,0 +1,59 @@
+package testing
+
+import (
+	"context"
+	"reflect"
+	"sync"
+
+	"github.com/prysmaticlabs/prysm/v5/api/client/beacon/iface"
+	"go.uber.org/mock/gomock"
+)
+
+var (
+	_ = iface.HealthNode(&MockHealthClient{})
+)
+
+// MockHealthClient is a mock of HealthClient interface.
+type MockHealthClient struct {
+	ctrl     *gomock.Controller
+	recorder *MockHealthClientMockRecorder
+	sync.Mutex
+}
+
+// MockHealthClientMockRecorder is the mock recorder for MockHealthClient.
+type MockHealthClientMockRecorder struct {
+	mock *MockHealthClient
+}
+
+// IsHealthy mocks base method.
+func (m *MockHealthClient) IsHealthy(arg0 context.Context) bool {
+	m.Lock()
+	defer m.Unlock()
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "IsHealthy", arg0)
+	ret0, ok := ret[0].(bool)
+	if !ok {
+		return false
+	}
+	return ret0
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use.
+func (m *MockHealthClient) EXPECT() *MockHealthClientMockRecorder {
+	return m.recorder
+}
+
+// IsHealthy indicates an expected call of IsHealthy.
+func (mr *MockHealthClientMockRecorder) IsHealthy(arg0 any) *gomock.Call {
+	mr.mock.Lock()
+	defer mr.mock.Unlock()
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "IsHealthy", reflect.TypeOf((*MockHealthClient)(nil).IsHealthy), arg0)
+}
+
+// NewMockHealthClient creates a new mock instance.
+func NewMockHealthClient(ctrl *gomock.Controller) *MockHealthClient {
+	mock := &MockHealthClient{ctrl: ctrl}
+	mock.recorder = &MockHealthClientMockRecorder{mock}
+	return mock
+}
--- a/api/client/builder/BUILD.bazel
+++ b/api/client/builder/BUILD.bazel
@@ -11,6 +11,7 @@ go_library(
    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/builder",
    visibility = ["//visibility:public"],
    deps = [
+        "//api:go_default_library",
        "//api/server/structs:go_default_library",
        "//config/fieldparams:go_default_library",
        "//consensus-types:go_default_library",
@@ -28,6 +29,7 @@ go_library(
        "@com_github_prysmaticlabs_fastssz//:go_default_library",
        "@com_github_sirupsen_logrus//:go_default_library",
        "@io_opencensus_go//trace:go_default_library",
+        "@org_golang_google_protobuf//proto:go_default_library",
    ],
 )

@@ -49,9 +51,11 @@ go_test(
        "//math:go_default_library",
        "//proto/engine/v1:go_default_library",
        "//proto/prysm/v1alpha1:go_default_library",
+        "//runtime/version:go_default_library",
        "//testing/assert:go_default_library",
        "//testing/require:go_default_library",
        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
        "@com_github_prysmaticlabs_go_bitfield//:go_default_library",
        "@com_github_sirupsen_logrus//:go_default_library",
    ],
--- a/api/client/builder/bid.go
+++ b/api/client/builder/bid.go
@@ -6,6 +6,7 @@ import (
 	consensus_types "github.com/prysmaticlabs/prysm/v5/consensus-types"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/runtime/version"
 )
@@ -22,7 +23,7 @@ type SignedBid interface {
 type Bid interface {
 	Header() (interfaces.ExecutionData, error)
 	BlobKzgCommitments() ([][]byte, error)
-	Value() []byte
+	Value() primitives.Wei
 	Pubkey() []byte
 	Version() int
 	IsNil() bool
@@ -125,8 +126,8 @@ func (b builderBid) Version() int {
 }

 // Value --
-func (b builderBid) Value() []byte {
-	return b.p.Value
+func (b builderBid) Value() primitives.Wei {
+	return primitives.LittleEndianBytesToWei(b.p.Value)
 }

 // Pubkey --
@@ -165,7 +166,7 @@ func WrappedBuilderBidCapella(p *ethpb.BuilderBidCapella) (Bid, error) {
 // Header returns the execution data interface.
 func (b builderBidCapella) Header() (interfaces.ExecutionData, error) {
 	// We have to convert big endian to little endian because the value is coming from the execution layer.
-	return blocks.WrappedExecutionPayloadHeaderCapella(b.p.Header, blocks.PayloadValueToWei(b.p.Value))
+	return blocks.WrappedExecutionPayloadHeaderCapella(b.p.Header)
 }

 // BlobKzgCommitments --
@@ -179,8 +180,8 @@ func (b builderBidCapella) Version() int {
 }

 // Value --
-func (b builderBidCapella) Value() []byte {
-	return b.p.Value
+func (b builderBidCapella) Value() primitives.Wei {
+	return primitives.LittleEndianBytesToWei(b.p.Value)
 }

 // Pubkey --
@@ -222,8 +223,8 @@ func (b builderBidDeneb) Version() int {
 }

 // Value --
-func (b builderBidDeneb) Value() []byte {
-	return b.p.Value
+func (b builderBidDeneb) Value() primitives.Wei {
+	return primitives.LittleEndianBytesToWei(b.p.Value)
 }

 // Pubkey --
@@ -249,7 +250,7 @@ func (b builderBidDeneb) HashTreeRootWith(hh *ssz.Hasher) error {
 // Header --
 func (b builderBidDeneb) Header() (interfaces.ExecutionData, error) {
 	// We have to convert big endian to little endian because the value is coming from the execution layer.
-	return blocks.WrappedExecutionPayloadHeaderDeneb(b.p.Header, blocks.PayloadValueToWei(b.p.Value))
+	return blocks.WrappedExecutionPayloadHeaderDeneb(b.p.Header)
 }

 // BlobKzgCommitments --
--- a/api/client/builder/client.go
+++ b/api/client/builder/client.go
@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"math/big"
 	"net"
 	"net/http"
 	"net/url"
@@ -14,11 +13,11 @@ import (
 	"text/template"

 	"github.com/pkg/errors"
+	"github.com/prysmaticlabs/prysm/v5/api"
 	"github.com/prysmaticlabs/prysm/v5/api/server/structs"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/v5/monitoring/tracing"
 	v1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
@@ -282,127 +281,68 @@ func (c *Client) RegisterValidator(ctx context.Context, svr []*ethpb.SignedValid
 	return err
 }

+var errResponseVersionMismatch = errors.New("builder API response uses a different version than requested in " + api.VersionHeader + " header")
+
 // 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) {
 	if !sb.IsBlinded() {
 		return nil, nil, errNotBlinded
 	}
-	switch sb.Version() {
-	case version.Bellatrix:
-		psb, err := sb.PbBlindedBellatrixBlock()
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not get protobuf block")
-		}
-		b, err := structs.SignedBlindedBeaconBlockBellatrixFromConsensus(&ethpb.SignedBlindedBeaconBlockBellatrix{Block: psb.Block, Signature: bytesutil.SafeCopyBytes(psb.Signature)})
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not convert SignedBlindedBeaconBlockBellatrix to json marshalable type")
-		}
-		body, err := json.Marshal(b)
-		if err != nil {
-			return nil, nil, errors.Wrap(err, "error encoding the SignedBlindedBeaconBlockBellatrix value body in SubmitBlindedBlock")
-		}
-		versionOpt := func(r *http.Request) {
-			r.Header.Add("Eth-Consensus-Version", version.String(version.Bellatrix))
-		}
-		rb, err := c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body), versionOpt)

-		if err != nil {
-			return nil, nil, errors.Wrap(err, "error posting the SignedBlindedBeaconBlockBellatrix to the builder api")
-		}
-		ep := &ExecPayloadResponse{}
-		if err := json.Unmarshal(rb, ep); err != nil {
-			return nil, nil, errors.Wrap(err, "error unmarshaling the builder SubmitBlindedBlock response")
-		}
-		if strings.ToLower(ep.Version) != version.String(version.Bellatrix) {
-			return nil, nil, errors.New("not a bellatrix payload")
-		}
-		p, err := ep.ToProto()
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not extract proto message from payload")
-		}
-		payload, err := blocks.WrappedExecutionPayload(p)
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not wrap execution payload in interface")
-		}
-		return payload, nil, nil
-	case version.Capella:
-		psb, err := sb.PbBlindedCapellaBlock()
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not get protobuf block")
-		}
-		b, err := structs.SignedBlindedBeaconBlockCapellaFromConsensus(&ethpb.SignedBlindedBeaconBlockCapella{Block: psb.Block, Signature: bytesutil.SafeCopyBytes(psb.Signature)})
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not convert SignedBlindedBeaconBlockCapella to json marshalable type")
-		}
-		body, err := json.Marshal(b)
-		if err != nil {
-			return nil, nil, errors.Wrap(err, "error encoding the SignedBlindedBeaconBlockCapella value body in SubmitBlindedBlockCapella")
-		}
-		versionOpt := func(r *http.Request) {
-			r.Header.Add("Eth-Consensus-Version", version.String(version.Capella))
-		}
-		rb, err := c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body), versionOpt)
-
-		if err != nil {
-			return nil, nil, errors.Wrap(err, "error posting the SignedBlindedBeaconBlockCapella to the builder api")
-		}
-		ep := &ExecPayloadResponseCapella{}
-		if err := json.Unmarshal(rb, ep); err != nil {
-			return nil, nil, errors.Wrap(err, "error unmarshaling the builder SubmitBlindedBlockCapella response")
-		}
-		if strings.ToLower(ep.Version) != version.String(version.Capella) {
-			return nil, nil, errors.New("not a capella payload")
-		}
-		p, err := ep.ToProto()
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not extract proto message from payload")
-		}
-		payload, err := blocks.WrappedExecutionPayloadCapella(p, big.NewInt(0))
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not wrap execution payload in interface")
-		}
-		return payload, nil, nil
-	case version.Deneb:
-		psb, err := sb.PbBlindedDenebBlock()
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not get protobuf block")
-		}
-		b, err := structs.SignedBlindedBeaconBlockDenebFromConsensus(&ethpb.SignedBlindedBeaconBlockDeneb{Message: psb.Message, Signature: bytesutil.SafeCopyBytes(psb.Signature)})
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not convert SignedBlindedBeaconBlockDeneb to json marshalable type")
-		}
-		body, err := json.Marshal(b)
-		if err != nil {
-			return nil, nil, errors.Wrap(err, "error encoding the SignedBlindedBeaconBlockDeneb value body in SubmitBlindedBlockDeneb")
-		}
-
-		versionOpt := func(r *http.Request) {
-			r.Header.Add("Eth-Consensus-Version", version.String(version.Deneb))
-		}
-		rb, err := c.do(ctx, http.MethodPost, postBlindedBeaconBlockPath, bytes.NewBuffer(body), versionOpt)
-		if err != nil {
-			return nil, nil, errors.Wrap(err, "error posting the SignedBlindedBeaconBlockDeneb to the builder api")
-		}
-		ep := &ExecPayloadResponseDeneb{}
-		if err := json.Unmarshal(rb, ep); err != nil {
-			return nil, nil, errors.Wrap(err, "error unmarshaling the builder SubmitBlindedBlockDeneb response")
-		}
-		if strings.ToLower(ep.Version) != version.String(version.Deneb) {
-			return nil, nil, errors.New("not a deneb payload")
-		}
-		p, blobBundle, err := ep.ToProto()
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not extract proto message from payload")
-		}
-		payload, err := blocks.WrappedExecutionPayloadDeneb(p, big.NewInt(0))
-		if err != nil {
-			return nil, nil, errors.Wrapf(err, "could not wrap execution payload in interface")
-		}
-		return payload, blobBundle, nil
-	default:
-		return nil, nil, fmt.Errorf("unsupported block version %s", version.String(sb.Version()))
+	// massage the proto struct type data into the api response type.
+	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")
+	}
+	postOpts := func(r *http.Request) {
+		r.Header.Add("Eth-Consensus-Version", 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")
+	}
+	// 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.
+	ep := &ExecutionPayloadResponse{}
+	if err := json.Unmarshal(rb, ep); err != nil {
+		return nil, nil, errors.Wrap(err, "error unmarshaling the builder 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)
+	}
+	// 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
+	}
+	ed, err := blocks.NewWrappedExecutionData(pb)
+	if err != nil {
+		return nil, nil, err
+	}
+	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 ed, bbpb, nil
+	}
+	return ed, nil, nil
 }

 // Status asks the remote builder server for a health check. A response of 200 with an empty body is the success/healthy
--- a/api/client/builder/client_test.go
+++ b/api/client/builder/client_test.go
@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"math/big"
 	"net/http"
 	"net/url"
 	"strconv"
@@ -16,6 +15,7 @@ import (
 	"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"
 	types "github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	v1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
@@ -198,12 +198,12 @@ func TestClient_GetHeader(t *testing.T) {
 		require.NoError(t, err)
 		require.Equal(t, true, bytes.Equal(expectedTxRoot, withdrawalsRoot))
 		require.Equal(t, uint64(1), bidHeader.GasUsed())
-		value, err := stringToUint256("652312848583266388373324160190187140051835877600158453279131187530910662656")
+		// this matches the value in the testExampleHeaderResponse
+		bidStr := "652312848583266388373324160190187140051835877600158453279131187530910662656"
+		value, err := stringToUint256(bidStr)
 		require.NoError(t, err)
-		require.Equal(t, fmt.Sprintf("%#x", value.SSZBytes()), fmt.Sprintf("%#x", bid.Value()))
-		bidValue := bytesutil.ReverseByteOrder(bid.Value())
-		require.DeepEqual(t, bidValue, value.Bytes())
-		require.DeepEqual(t, big.NewInt(0).SetBytes(bidValue), value.Int)
+		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{
@@ -230,12 +230,11 @@ func TestClient_GetHeader(t *testing.T) {
 		withdrawalsRoot, err := bidHeader.WithdrawalsRoot()
 		require.NoError(t, err)
 		require.Equal(t, true, bytes.Equal(expectedWithdrawalsRoot, withdrawalsRoot))
-		value, err := stringToUint256("652312848583266388373324160190187140051835877600158453279131187530910662656")
+		bidStr := "652312848583266388373324160190187140051835877600158453279131187530910662656"
+		value, err := stringToUint256(bidStr)
 		require.NoError(t, err)
-		require.Equal(t, fmt.Sprintf("%#x", value.SSZBytes()), fmt.Sprintf("%#x", bid.Value()))
-		bidValue := bytesutil.ReverseByteOrder(bid.Value())
-		require.DeepEqual(t, bidValue, value.Bytes())
-		require.DeepEqual(t, big.NewInt(0).SetBytes(bidValue), value.Int)
+		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{
@@ -262,12 +261,13 @@ func TestClient_GetHeader(t *testing.T) {
 		withdrawalsRoot, err := bidHeader.WithdrawalsRoot()
 		require.NoError(t, err)
 		require.Equal(t, true, bytes.Equal(expectedWithdrawalsRoot, withdrawalsRoot))
-		value, err := stringToUint256("652312848583266388373324160190187140051835877600158453279131187530910662656")
+
+		bidStr := "652312848583266388373324160190187140051835877600158453279131187530910662656"
+		value, err := stringToUint256(bidStr)
 		require.NoError(t, err)
-		require.Equal(t, fmt.Sprintf("%#x", value.SSZBytes()), fmt.Sprintf("%#x", bid.Value()))
-		bidValue := bytesutil.ReverseByteOrder(bid.Value())
-		require.DeepEqual(t, bidValue, value.Bytes())
-		require.DeepEqual(t, big.NewInt(0).SetBytes(bidValue), value.Int)
+		require.Equal(t, 0, value.Int.Cmp(primitives.WeiToBigInt(bid.Value())))
+		require.Equal(t, bidStr, primitives.WeiToBigInt(bid.Value()).String())
+
 		kcgCommitments, err := bid.BlobKzgCommitments()
 		require.NoError(t, err)
 		require.Equal(t, len(kcgCommitments) > 0, true)
@@ -321,6 +321,8 @@ func TestSubmitBlindedBlock(t *testing.T) {
 			Transport: roundtrip(func(r *http.Request) (*http.Response, error) {
 				require.Equal(t, postBlindedBeaconBlockPath, r.URL.Path)
 				require.Equal(t, "bellatrix", r.Header.Get("Eth-Consensus-Version"))
+				require.Equal(t, "application/json", r.Header.Get("Content-Type"))
+				require.Equal(t, "application/json", r.Header.Get("Accept"))
 				return &http.Response{
 					StatusCode: http.StatusOK,
 					Body:       io.NopCloser(bytes.NewBufferString(testExampleExecutionPayload)),
@@ -347,6 +349,8 @@ func TestSubmitBlindedBlock(t *testing.T) {
 			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, "application/json", r.Header.Get("Content-Type"))
+				require.Equal(t, "application/json", r.Header.Get("Accept"))
 				return &http.Response{
 					StatusCode: http.StatusOK,
 					Body:       io.NopCloser(bytes.NewBufferString(testExampleExecutionPayloadCapella)),
@@ -376,6 +380,8 @@ func TestSubmitBlindedBlock(t *testing.T) {
 			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, "application/json", r.Header.Get("Content-Type"))
+				require.Equal(t, "application/json", r.Header.Get("Accept"))
 				var req structs.SignedBlindedBeaconBlockDeneb
 				err := json.NewDecoder(r.Body).Decode(&req)
 				require.NoError(t, err)
@@ -426,7 +432,7 @@ func TestSubmitBlindedBlock(t *testing.T) {
 		sbbb, err := blocks.NewSignedBeaconBlock(testSignedBlindedBeaconBlockBellatrix(t))
 		require.NoError(t, err)
 		_, _, err = c.SubmitBlindedBlock(ctx, sbbb)
-		require.ErrorContains(t, "not a bellatrix payload", err)
+		require.ErrorIs(t, err, errResponseVersionMismatch)
 	})
 	t.Run("not blinded", func(t *testing.T) {
 		sbb, err := blocks.NewSignedBeaconBlock(&eth.SignedBeaconBlockBellatrix{Block: &eth.BeaconBlockBellatrix{Body: &eth.BeaconBlockBodyBellatrix{ExecutionPayload: &v1.ExecutionPayload{}}}})
--- a/api/client/builder/types.go
+++ b/api/client/builder/types.go
@@ -9,11 +9,15 @@ import (
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
 	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
+	consensusblocks "github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/interfaces"
 	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"
 )

 var errInvalidUint256 = errors.New("invalid Uint256")
@@ -44,6 +48,9 @@ func sszBytesToUint256(b []byte) (Uint256, error) {

 // SSZBytes creates an ssz-style (little-endian byte slice) representation of the Uint256.
 func (s Uint256) SSZBytes() []byte {
+	if s.Int == nil {
+		s.Int = big.NewInt(0)
+	}
 	if !math.IsValidUint256(s.Int) {
 		return []byte{}
 	}
@@ -91,6 +98,9 @@ func (s Uint256) MarshalJSON() ([]byte, error) {

 // MarshalText returns a text byte representation of Uint256.
 func (s Uint256) MarshalText() ([]byte, error) {
+	if s.Int == nil {
+		s.Int = big.NewInt(0)
+	}
 	if !math.IsValidUint256(s.Int) {
 		return nil, errors.Wrapf(errInvalidUint256, "value=%s", s.Int)
 	}
@@ -146,6 +156,8 @@ func (bb *BuilderBid) ToProto() (*eth.BuilderBid, error) {
 	}
 	return &eth.BuilderBid{
 		Header: header,
+		// Note that SSZBytes() reverses byte order for the little-endian representation.
+		// Uint256.Bytes() is big-endian, SSZBytes takes this value and reverses it.
 		Value:  bb.Value.SSZBytes(),
 		Pubkey: bb.Pubkey,
 	}, nil
@@ -265,6 +277,11 @@ func (r *ExecPayloadResponse) ToProto() (*v1.ExecutionPayload, error) {
 	return r.Data.ToProto()
 }

+func (r *ExecutionPayload) PayloadProto() (proto.Message, error) {
+	pb, err := r.ToProto()
+	return pb, err
+}
+
 // ToProto returns a ExecutionPayload Proto
 func (p *ExecutionPayload) ToProto() (*v1.ExecutionPayload, error) {
 	txs := make([][]byte, len(p.Transactions))
@@ -396,6 +413,51 @@ func FromProtoDeneb(payload *v1.ExecutionPayloadDeneb) (ExecutionPayloadDeneb, e
 	}, nil
 }

+var errInvalidTypeConversion = errors.New("unable to translate between api and foreign type")
+
+// ExecutionPayloadResponseFromData converts an ExecutionData interface value to a payload response.
+// This involves serializing the execution payload value so that the abstract payload envelope can be used.
+func ExecutionPayloadResponseFromData(ed interfaces.ExecutionData, bundle *v1.BlobsBundle) (*ExecutionPayloadResponse, error) {
+	pb := ed.Proto()
+	var data interface{}
+	var err error
+	var ver string
+	switch pbStruct := pb.(type) {
+	case *v1.ExecutionPayload:
+		ver = version.String(version.Bellatrix)
+		data, err = FromProto(pbStruct)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to convert a Bellatrix ExecutionPayload to an API response")
+		}
+	case *v1.ExecutionPayloadCapella:
+		ver = version.String(version.Capella)
+		data, err = FromProtoCapella(pbStruct)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to convert a Capella ExecutionPayload to an API response")
+		}
+	case *v1.ExecutionPayloadDeneb:
+		ver = version.String(version.Deneb)
+		payloadStruct, err := FromProtoDeneb(pbStruct)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to convert a Deneb ExecutionPayload to an API response")
+		}
+		data = &ExecutionPayloadDenebAndBlobsBundle{
+			ExecutionPayload: &payloadStruct,
+			BlobsBundle:      FromBundleProto(bundle),
+		}
+	default:
+		return nil, errInvalidTypeConversion
+	}
+	encoded, err := json.Marshal(data)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to marshal execution payload version=%s", ver)
+	}
+	return &ExecutionPayloadResponse{
+		Version: ver,
+		Data:    encoded,
+	}, nil
+}
+
 // ExecHeaderResponseCapella is the response of builder API /eth/v1/builder/header/{slot}/{parent_hash}/{pubkey} for Capella.
 type ExecHeaderResponseCapella struct {
 	Data struct {
@@ -424,6 +486,8 @@ func (bb *BuilderBidCapella) ToProto() (*eth.BuilderBidCapella, error) {
 	}
 	return &eth.BuilderBidCapella{
 		Header: header,
+		// Note that SSZBytes() reverses byte order for the little-endian representation.
+		// Uint256.Bytes() is big-endian, SSZBytes takes this value and reverses it.
 		Value:  bytesutil.SafeCopyBytes(bb.Value.SSZBytes()),
 		Pubkey: bytesutil.SafeCopyBytes(bb.Pubkey),
 	}, nil
@@ -523,6 +587,42 @@ type ExecPayloadResponseCapella struct {
 	Data    ExecutionPayloadCapella `json:"data"`
 }

+// ExecutionPayloadResponse allows for unmarshaling just the Version field of the payload.
+// This allows it to return different ExecutionPayload types based on the version field.
+type ExecutionPayloadResponse struct {
+	Version string          `json:"version"`
+	Data    json.RawMessage `json:"data"`
+}
+
+// ParsedPayload can retrieve the underlying protobuf message for the given execution payload response.
+type ParsedPayload interface {
+	PayloadProto() (proto.Message, error)
+}
+
+// BlobBundler can retrieve the underlying blob bundle protobuf message for the given execution payload response.
+type BlobBundler interface {
+	BundleProto() (*v1.BlobsBundle, error)
+}
+
+func (r *ExecutionPayloadResponse) ParsePayload() (ParsedPayload, error) {
+	var toProto ParsedPayload
+	switch r.Version {
+	case version.String(version.Bellatrix):
+		toProto = &ExecutionPayload{}
+	case version.String(version.Capella):
+		toProto = &ExecutionPayloadCapella{}
+	case version.String(version.Deneb):
+		toProto = &ExecutionPayloadDenebAndBlobsBundle{}
+	default:
+		return nil, consensusblocks.ErrUnsupportedVersion
+	}
+
+	if err := json.Unmarshal(r.Data, toProto); err != nil {
+		return nil, errors.Wrap(err, "failed to unmarshal the response .Data field with the stated version schema")
+	}
+	return toProto, nil
+}
+
 // ExecutionPayloadCapella is a field of ExecPayloadResponseCapella.
 type ExecutionPayloadCapella struct {
 	ParentHash    hexutil.Bytes   `json:"parent_hash"`
@@ -547,6 +647,11 @@ func (r *ExecPayloadResponseCapella) ToProto() (*v1.ExecutionPayloadCapella, err
 	return r.Data.ToProto()
 }

+func (p *ExecutionPayloadCapella) PayloadProto() (proto.Message, error) {
+	pb, err := p.ToProto()
+	return pb, err
+}
+
 // ToProto returns a ExecutionPayloadCapella Proto.
 func (p *ExecutionPayloadCapella) ToProto() (*v1.ExecutionPayloadCapella, error) {
 	txs := make([][]byte, len(p.Transactions))
@@ -921,8 +1026,10 @@ func (bb *BuilderBidDeneb) ToProto() (*eth.BuilderBidDeneb, error) {
 	return &eth.BuilderBidDeneb{
 		Header:             header,
 		BlobKzgCommitments: kzgCommitments,
-		Value:              bytesutil.SafeCopyBytes(bb.Value.SSZBytes()),
-		Pubkey:             bytesutil.SafeCopyBytes(bb.Pubkey),
+		// Note that SSZBytes() reverses byte order for the little-endian representation.
+		// Uint256.Bytes() is big-endian, SSZBytes takes this value and reverses it.
+		Value:  bytesutil.SafeCopyBytes(bb.Value.SSZBytes()),
+		Pubkey: bytesutil.SafeCopyBytes(bb.Pubkey),
 	}, nil
 }

@@ -1128,6 +1235,12 @@ func (r *ExecPayloadResponseDeneb) ToProto() (*v1.ExecutionPayloadDeneb, *v1.Blo
 	if r.Data == nil {
 		return nil, nil, errors.New("data field in response is empty")
 	}
+	if r.Data.ExecutionPayload == nil {
+		return nil, nil, errors.Wrap(consensusblocks.ErrNilObject, "nil execution payload")
+	}
+	if r.Data.BlobsBundle == nil {
+		return nil, nil, errors.Wrap(consensusblocks.ErrNilObject, "nil blobs bundle")
+	}
 	payload, err := r.Data.ExecutionPayload.ToProto()
 	if err != nil {
 		return nil, nil, err
@@ -1139,8 +1252,26 @@ func (r *ExecPayloadResponseDeneb) ToProto() (*v1.ExecutionPayloadDeneb, *v1.Blo
 	return payload, bundle, nil
 }

+func (r *ExecutionPayloadDenebAndBlobsBundle) PayloadProto() (proto.Message, error) {
+	if r.ExecutionPayload == nil {
+		return nil, errors.Wrap(consensusblocks.ErrNilObject, "nil execution payload in combined deneb payload")
+	}
+	pb, err := r.ExecutionPayload.ToProto()
+	return pb, err
+}
+
+func (r *ExecutionPayloadDenebAndBlobsBundle) BundleProto() (*v1.BlobsBundle, error) {
+	if r.BlobsBundle == nil {
+		return nil, errors.Wrap(consensusblocks.ErrNilObject, "nil blobs bundle")
+	}
+	return r.BlobsBundle.ToProto()
+}
+
 // ToProto returns the ExecutionPayloadDeneb Proto.
 func (p *ExecutionPayloadDeneb) ToProto() (*v1.ExecutionPayloadDeneb, error) {
+	if p == nil {
+		return nil, errors.Wrap(consensusblocks.ErrNilObject, "nil execution payload")
+	}
 	txs := make([][]byte, len(p.Transactions))
 	for i := range p.Transactions {
 		txs[i] = bytesutil.SafeCopyBytes(p.Transactions[i])
--- a/api/client/builder/types_test.go
+++ b/api/client/builder/types_test.go
@@ -12,12 +12,15 @@ import (
 	"testing"

 	"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"
 )
@@ -1600,7 +1603,6 @@ func TestBuilderBidUnmarshalUint256(t *testing.T) {
 	require.NoError(t, expectedValue.UnmarshalText([]byte(base10)))
 	r := &ExecHeaderResponse{}
 	require.NoError(t, json.Unmarshal([]byte(testBuilderBid), r))
-	//require.Equal(t, expectedValue, r.Data.Message.Value)
 	marshaled := r.Data.Message.Value.String()
 	require.Equal(t, base10, marshaled)
 	require.Equal(t, 0, expectedValue.Cmp(r.Data.Message.Value.Int))
@@ -1907,3 +1909,41 @@ func TestErrorMessage_non200Err(t *testing.T) {
 		})
 	}
 }
+
+func TestEmptyResponseBody(t *testing.T) {
+	t.Run("empty buffer", func(t *testing.T) {
+		var b []byte
+		r := &ExecutionPayloadResponse{}
+		err := json.Unmarshal(b, r)
+		var syntaxError *json.SyntaxError
+		ok := errors.As(err, &syntaxError)
+		require.Equal(t, true, ok)
+	})
+	t.Run("empty object", func(t *testing.T) {
+		empty := []byte("{}")
+		emptyResponse := &ExecutionPayloadResponse{}
+		require.NoError(t, json.Unmarshal(empty, emptyResponse))
+		_, err := emptyResponse.ParsePayload()
+		require.ErrorIs(t, err, consensusblocks.ErrUnsupportedVersion)
+	})
+	versions := []int{version.Bellatrix, version.Capella, version.Deneb}
+	for i := range versions {
+		vstr := version.String(versions[i])
+		t.Run("populated version without payload"+vstr, func(t *testing.T) {
+			in := &ExecutionPayloadResponse{Version: vstr}
+			encoded, err := json.Marshal(in)
+			require.NoError(t, err)
+			epr := &ExecutionPayloadResponse{}
+			require.NoError(t, json.Unmarshal(encoded, epr))
+			pp, err := epr.ParsePayload()
+			require.NoError(t, err)
+			pb, err := pp.PayloadProto()
+			if err == nil {
+				require.NoError(t, err)
+				require.Equal(t, false, pb == nil)
+			} else {
+				require.ErrorIs(t, err, consensusblocks.ErrNilObject)
+			}
+		})
+	}
+}
--- a/api/client/errors.go
+++ b/api/client/errors.go
@@ -21,6 +21,9 @@ var ErrNotFound = errors.Wrap(ErrNotOK, "recv 404 NotFound response from API")
 // ErrInvalidNodeVersion indicates that the /eth/v1/node/version API response format was not recognized.
 var ErrInvalidNodeVersion = errors.New("invalid node version response")

+// ErrConnectionIssue represents a connection problem.
+var ErrConnectionIssue = errors.New("could not connect")
+
 // Non200Err is a function that parses an HTTP response to handle responses that are not 200 with a formatted error.
 func Non200Err(response *http.Response) error {
 	bodyBytes, err := io.ReadAll(response.Body)
--- a/api/client/event/BUILD.bazel
+++ b/api/client/event/BUILD.bazel
@@ -0,0 +1,24 @@
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["event_stream.go"],
+    importpath = "github.com/prysmaticlabs/prysm/v5/api/client/event",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//api:go_default_library",
+        "//api/client:go_default_library",
+        "@com_github_pkg_errors//:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["event_stream_test.go"],
+    embed = [":go_default_library"],
+    deps = [
+        "//testing/require:go_default_library",
+        "@com_github_sirupsen_logrus//:go_default_library",
+    ],
+)
--- a/api/client/event/event_stream.go
+++ b/api/client/event/event_stream.go
@@ -0,0 +1,148 @@
+package event
+
+import (
+	"bufio"
+	"context"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/pkg/errors"
+	"github.com/prysmaticlabs/prysm/v5/api"
+	"github.com/prysmaticlabs/prysm/v5/api/client"
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	EventHead                        = "head"
+	EventBlock                       = "block"
+	EventAttestation                 = "attestation"
+	EventVoluntaryExit               = "voluntary_exit"
+	EventBlsToExecutionChange        = "bls_to_execution_change"
+	EventProposerSlashing            = "proposer_slashing"
+	EventAttesterSlashing            = "attester_slashing"
+	EventFinalizedCheckpoint         = "finalized_checkpoint"
+	EventChainReorg                  = "chain_reorg"
+	EventContributionAndProof        = "contribution_and_proof"
+	EventLightClientFinalityUpdate   = "light_client_finality_update"
+	EventLightClientOptimisticUpdate = "light_client_optimistic_update"
+	EventPayloadAttributes           = "payload_attributes"
+	EventBlobSidecar                 = "blob_sidecar"
+	EventError                       = "error"
+	EventConnectionError             = "connection_error"
+)
+
+var (
+	_ = EventStreamClient(&EventStream{})
+)
+
+var DefaultEventTopics = []string{EventHead}
+
+type EventStreamClient interface {
+	Subscribe(eventsChannel chan<- *Event)
+}
+
+type Event struct {
+	EventType string
+	Data      []byte
+}
+
+// EventStream is responsible for subscribing to the Beacon API events endpoint
+// and dispatching received events to subscribers.
+type EventStream struct {
+	ctx        context.Context
+	httpClient *http.Client
+	host       string
+	topics     []string
+}
+
+func NewEventStream(ctx context.Context, httpClient *http.Client, host string, topics []string) (*EventStream, error) {
+	// Check if the host is a valid URL
+	_, err := url.ParseRequestURI(host)
+	if err != nil {
+		return nil, err
+	}
+	if len(topics) == 0 {
+		return nil, errors.New("no topics provided")
+	}
+
+	return &EventStream{
+		ctx:        ctx,
+		httpClient: httpClient,
+		host:       host,
+		topics:     topics,
+	}, nil
+}
+
+func (h *EventStream) Subscribe(eventsChannel chan<- *Event) {
+	allTopics := strings.Join(h.topics, ",")
+	log.WithField("topics", allTopics).Info("Listening to Beacon API events")
+	fullUrl := h.host + "/eth/v1/events?topics=" + allTopics
+	req, err := http.NewRequestWithContext(h.ctx, http.MethodGet, fullUrl, nil)
+	if err != nil {
+		eventsChannel <- &Event{
+			EventType: EventConnectionError,
+			Data:      []byte(errors.Wrap(err, "failed to create HTTP request").Error()),
+		}
+	}
+	req.Header.Set("Accept", api.EventStreamMediaType)
+	req.Header.Set("Connection", api.KeepAlive)
+	resp, err := h.httpClient.Do(req)
+	if err != nil {
+		eventsChannel <- &Event{
+			EventType: EventConnectionError,
+			Data:      []byte(errors.Wrap(err, client.ErrConnectionIssue.Error()).Error()),
+		}
+	}
+
+	defer func() {
+		if closeErr := resp.Body.Close(); closeErr != nil {
+			log.WithError(closeErr).Error("Failed to close events response body")
+		}
+	}()
+	// Create a new scanner to read lines from the response body
+	scanner := bufio.NewScanner(resp.Body)
+
+	var eventType, data string // Variables to store event type and data
+
+	// Iterate over lines of the event stream
+	for scanner.Scan() {
+		select {
+		case <-h.ctx.Done():
+			log.Info("Context canceled, stopping event stream")
+			close(eventsChannel)
+			return
+		default:
+			line := scanner.Text() // TODO(13730): scanner does not handle /r and does not fully adhere to https://html.spec.whatwg.org/multipage/server-sent-events.html#the-eventsource-interface
+			// Handle the event based on your specific format
+			if line == "" {
+				// Empty line indicates the end of an event
+				if eventType != "" && data != "" {
+					// Process the event when both eventType and data are set
+					eventsChannel <- &Event{EventType: eventType, Data: []byte(data)}
+				}
+
+				// Reset eventType and data for the next event
+				eventType, data = "", ""
+				continue
+			}
+			et, ok := strings.CutPrefix(line, "event: ")
+			if ok {
+				// Extract event type from the "event" field
+				eventType = et
+			}
+			d, ok := strings.CutPrefix(line, "data: ")
+			if ok {
+				// Extract data from the "data" field
+				data = d
+			}
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		eventsChannel <- &Event{
+			EventType: EventConnectionError,
+			Data:      []byte(errors.Wrap(err, errors.Wrap(client.ErrConnectionIssue, "scanner failed").Error()).Error()),
+		}
+	}
+}
--- a/api/client/event/event_stream_test.go
+++ b/api/client/event/event_stream_test.go
@@ -0,0 +1,80 @@
+package event
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/prysmaticlabs/prysm/v5/testing/require"
+	log "github.com/sirupsen/logrus"
+)
+
+func TestNewEventStream(t *testing.T) {
+	validURL := "http://localhost:8080"
+	invalidURL := "://invalid"
+	topics := []string{"topic1", "topic2"}
+
+	tests := []struct {
+		name    string
+		host    string
+		topics  []string
+		wantErr bool
+	}{
+		{"Valid input", validURL, topics, false},
+		{"Invalid URL", invalidURL, topics, true},
+		{"No topics", validURL, []string{}, true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := NewEventStream(context.Background(), &http.Client{}, tt.host, tt.topics)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("NewEventStream() error = %v, wantErr %v", err, tt.wantErr)
+			}
+		})
+	}
+}
+
+func TestEventStream(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/eth/v1/events", func(w http.ResponseWriter, r *http.Request) {
+		flusher, ok := w.(http.Flusher)
+		require.Equal(t, true, ok)
+		for i := 1; i <= 2; i++ {
+			_, err := fmt.Fprintf(w, "event: head\ndata: data%d\n\n", i)
+			require.NoError(t, err)
+			flusher.Flush()                    // Trigger flush to simulate streaming data
+			time.Sleep(100 * time.Millisecond) // Simulate delay between events
+		}
+	})
+	server := httptest.NewServer(mux)
+	defer server.Close()
+
+	topics := []string{"head"}
+	eventsChannel := make(chan *Event, 1)
+	stream, err := NewEventStream(context.Background(), http.DefaultClient, server.URL, topics)
+	require.NoError(t, err)
+	go stream.Subscribe(eventsChannel)
+
+	// Collect events
+	var events []*Event
+
+	for len(events) != 2 {
+		select {
+		case event := <-eventsChannel:
+			log.Info(event)
+			events = append(events, event)
+		}
+	}
+
+	// Assertions to verify the events content
+	expectedData := []string{"data1", "data2"}
+	for i, event := range events {
+		if string(event.Data) != expectedData[i] {
+			t.Errorf("Expected event data %q, got %q", expectedData[i], string(event.Data))
+		}
+	}
+}
--- a/api/constants.go
+++ b/api/constants.go
@@ -4,4 +4,6 @@ const (
 	WebUrlPrefix        = "/v2/validator/"
 	WebApiUrlPrefix     = "/api/v2/validator/"
 	KeymanagerApiPrefix = "/eth/v1"
+	SystemLogsPrefix    = "health/logs"
+	AuthTokenFileName   = "auth-token"
 )
--- a/api/gateway/BUILD.bazel
+++ b/api/gateway/BUILD.bazel
@@ -14,7 +14,7 @@ go_library(
        "//validator:__subpackages__",
    ],
    deps = [
-        "//api/server:go_default_library",
+        "//api/server/middleware:go_default_library",
        "//runtime:go_default_library",
        "@com_github_gorilla_mux//:go_default_library",
        "@com_github_grpc_ecosystem_grpc_gateway_v2//runtime:go_default_library",
--- a/api/gateway/gateway.go
+++ b/api/gateway/gateway.go
@@ -11,7 +11,7 @@ import (
 	"github.com/gorilla/mux"
 	gwruntime "github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
 	"github.com/pkg/errors"
-	"github.com/prysmaticlabs/prysm/v5/api/server"
+	"github.com/prysmaticlabs/prysm/v5/api/server/middleware"
 	"github.com/prysmaticlabs/prysm/v5/runtime"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/connectivity"
@@ -104,7 +104,7 @@ func (g *Gateway) Start() {
 		}
 	}

-	corsMux := server.CorsHandler(g.cfg.allowedOrigins).Middleware(g.cfg.router)
+	corsMux := middleware.CorsHandler(g.cfg.allowedOrigins).Middleware(g.cfg.router)

 	if g.cfg.muxHandler != nil {
 		g.cfg.router.PathPrefix("/").HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
--- a/api/jwt.go
+++ b/api/jwt.go
@@ -0,0 +1,32 @@
+package api
+
+import (
+	"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
+// used for beacon node -> execution client
+// used for web client -> validator client
+func GenerateRandomHexString() (string, error) {
+	secret := make([]byte, 32)
+	randGen := rand.NewGenerator()
+	n, err := randGen.Read(secret)
+	if err != nil {
+		return "", err
+	} else if n != 32 {
+		return "", errors.New("rand: unexpected length")
+	}
+	return hexutil.Encode(secret), nil
+}
+
+// ValidateAuthToken validating auth token for web
+func ValidateAuthToken(token string) error {
+	b, err := hexutil.Decode(token)
+	// token should be hex-encoded and at least 256 bits
+	if err != nil || len(b) < 32 {
+		return errors.New("invalid auth token: token should be hex-encoded and at least 256 bits")
+	}
+	return nil
+}
--- a/api/jwt_test.go
+++ b/api/jwt_test.go
@@ -0,0 +1,13 @@
+package api
+
+import (
+	"testing"
+
+	"github.com/prysmaticlabs/prysm/v5/testing/require"
+)
+
+func TestGenerateRandomHexString(t *testing.T) {
+	token, err := GenerateRandomHexString()
+	require.NoError(t, err)
+	require.NoError(t, ValidateAuthToken(token))
+}
--- a/api/server/BUILD.bazel
+++ b/api/server/BUILD.bazel
@@ -2,29 +2,14 @@ load("@prysm//tools/go:def.bzl", "go_library", "go_test")

 go_library(
    name = "go_default_library",
-    srcs = [
-        "error.go",
-        "middleware.go",
-        "util.go",
-    ],
+    srcs = ["error.go"],
    importpath = "github.com/prysmaticlabs/prysm/v5/api/server",
    visibility = ["//visibility:public"],
-    deps = [
-        "@com_github_gorilla_mux//:go_default_library",
-        "@com_github_rs_cors//:go_default_library",
-    ],
 )

 go_test(
    name = "go_default_test",
-    srcs = [
-        "error_test.go",
-        "middleware_test.go",
-        "util_test.go",
-    ],
+    srcs = ["error_test.go"],
    embed = [":go_default_library"],
-    deps = [
-        "//testing/assert:go_default_library",
-        "//testing/require:go_default_library",
-    ],
+    deps = ["//testing/assert:go_default_library"],
 )
--- a/api/server/error.go
+++ b/api/server/error.go
@@ -1,6 +1,7 @@
 package server

 import (
+	"errors"
 	"fmt"
 	"strings"
 )
@@ -15,7 +16,8 @@ type DecodeError struct {
 // NewDecodeError wraps an error (either the initial decoding error or another DecodeError).
 // The current field that failed decoding must be passed in.
 func NewDecodeError(err error, field string) *DecodeError {
-	de, ok := err.(*DecodeError)
+	var de *DecodeError
+	ok := errors.As(err, &de)
 	if ok {
 		return &DecodeError{path: append([]string{field}, de.path...), err: de.err}
 	}
--- a/api/server/middleware.go
+++ b/api/server/middleware.go
@@ -1,32 +0,0 @@
-package server
-
-import (
-	"net/http"
-
-	"github.com/gorilla/mux"
-	"github.com/rs/cors"
-)
-
-// NormalizeQueryValuesHandler normalizes an input query of "key=value1,value2,value3" to "key=value1&key=value2&key=value3"
-func NormalizeQueryValuesHandler(next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		query := r.URL.Query()
-		NormalizeQueryValues(query)
-		r.URL.RawQuery = query.Encode()
-
-		next.ServeHTTP(w, r)
-	})
-}
-
-// CorsHandler sets the cors settings on api endpoints
-func CorsHandler(allowOrigins []string) mux.MiddlewareFunc {
-	c := cors.New(cors.Options{
-		AllowedOrigins:   allowOrigins,
-		AllowedMethods:   []string{http.MethodPost, http.MethodGet, http.MethodDelete, http.MethodOptions},
-		AllowCredentials: true,
-		MaxAge:           600,
-		AllowedHeaders:   []string{"*"},
-	})
-
-	return c.Handler
-}
--- a/api/server/middleware/BUILD.bazel
+++ b/api/server/middleware/BUILD.bazel
@@ -0,0 +1,29 @@
+load("@prysm//tools/go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "middleware.go",
+        "util.go",
+    ],
+    importpath = "github.com/prysmaticlabs/prysm/v5/api/server/middleware",
+    visibility = ["//visibility:public"],
+    deps = [
+        "@com_github_gorilla_mux//:go_default_library",
+        "@com_github_rs_cors//:go_default_library",
+    ],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = [
+        "middleware_test.go",
+        "util_test.go",
+    ],
+    embed = [":go_default_library"],
+    deps = [
+        "//api:go_default_library",
+        "//testing/assert:go_default_library",
+        "//testing/require:go_default_library",
+    ],
+)
--- a/api/server/middleware/middleware.go
+++ b/api/server/middleware/middleware.go
@@ -0,0 +1,112 @@
+package middleware
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+
+	"github.com/gorilla/mux"
+	"github.com/rs/cors"
+)
+
+// NormalizeQueryValuesHandler normalizes an input query of "key=value1,value2,value3" to "key=value1&key=value2&key=value3"
+func NormalizeQueryValuesHandler(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		query := r.URL.Query()
+		NormalizeQueryValues(query)
+		r.URL.RawQuery = query.Encode()
+
+		next.ServeHTTP(w, r)
+	})
+}
+
+// CorsHandler sets the cors settings on api endpoints
+func CorsHandler(allowOrigins []string) mux.MiddlewareFunc {
+	c := cors.New(cors.Options{
+		AllowedOrigins:   allowOrigins,
+		AllowedMethods:   []string{http.MethodPost, http.MethodGet, http.MethodDelete, http.MethodOptions},
+		AllowCredentials: true,
+		MaxAge:           600,
+		AllowedHeaders:   []string{"*"},
+	})
+
+	return c.Handler
+}
+
+// ContentTypeHandler checks request for the appropriate media types otherwise returning a http.StatusUnsupportedMediaType error
+func ContentTypeHandler(acceptedMediaTypes []string) mux.MiddlewareFunc {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			// skip the GET request
+			if r.Method == http.MethodGet {
+				next.ServeHTTP(w, r)
+				return
+			}
+			contentType := r.Header.Get("Content-Type")
+			if contentType == "" {
+				http.Error(w, "Content-Type header is missing", http.StatusUnsupportedMediaType)
+				return
+			}
+
+			accepted := false
+			for _, acceptedType := range acceptedMediaTypes {
+				if strings.Contains(strings.TrimSpace(contentType), strings.TrimSpace(acceptedType)) {
+					accepted = true
+					break
+				}
+			}
+
+			if !accepted {
+				http.Error(w, fmt.Sprintf("Unsupported media type: %s", contentType), http.StatusUnsupportedMediaType)
+				return
+			}
+
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
+// AcceptHeaderHandler checks if the client's response preference is handled
+func AcceptHeaderHandler(serverAcceptedTypes []string) mux.MiddlewareFunc {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			acceptHeader := r.Header.Get("Accept")
+			// header is optional and should skip if not provided
+			if acceptHeader == "" {
+				next.ServeHTTP(w, r)
+				return
+			}
+
+			accepted := false
+			acceptTypes := strings.Split(acceptHeader, ",")
+			// follows rules defined in https://datatracker.ietf.org/doc/html/rfc2616#section-14.1
+			for _, acceptType := range acceptTypes {
+				acceptType = strings.TrimSpace(acceptType)
+				if acceptType == "*/*" {
+					accepted = true
+					break
+				}
+				for _, serverAcceptedType := range serverAcceptedTypes {
+					if strings.HasPrefix(acceptType, serverAcceptedType) {
+						accepted = true
+						break
+					}
+					if acceptType != "/*" && strings.HasSuffix(acceptType, "/*") && strings.HasPrefix(serverAcceptedType, acceptType[:len(acceptType)-2]) {
+						accepted = true
+						break
+					}
+				}
+				if accepted {
+					break
+				}
+			}
+
+			if !accepted {
+				http.Error(w, fmt.Sprintf("Not Acceptable: %s", acceptHeader), http.StatusNotAcceptable)
+				return
+			}
+
+			next.ServeHTTP(w, r)
+		})
+	}
+}
--- a/api/server/middleware/middleware_test.go
+++ b/api/server/middleware/middleware_test.go
@@ -0,0 +1,204 @@
+package middleware
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/prysmaticlabs/prysm/v5/api"
+	"github.com/prysmaticlabs/prysm/v5/testing/require"
+)
+
+func TestNormalizeQueryValuesHandler(t *testing.T) {
+	nextHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, err := w.Write([]byte("next handler"))
+		require.NoError(t, err)
+	})
+
+	handler := NormalizeQueryValuesHandler(nextHandler)
+
+	tests := []struct {
+		name          string
+		inputQuery    string
+		expectedQuery string
+	}{
+		{
+			name:          "3 values",
+			inputQuery:    "key=value1,value2,value3",
+			expectedQuery: "key=value1&key=value2&key=value3", // replace with expected normalized value
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			req, err := http.NewRequest("GET", "/test?"+test.inputQuery, http.NoBody)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			rr := httptest.NewRecorder()
+			handler.ServeHTTP(rr, req)
+
+			if rr.Code != http.StatusOK {
+				t.Errorf("handler returned wrong status code: got %v want %v", rr.Code, http.StatusOK)
+			}
+
+			if req.URL.RawQuery != test.expectedQuery {
+				t.Errorf("query not normalized: got %v want %v", req.URL.RawQuery, test.expectedQuery)
+			}
+
+			if rr.Body.String() != "next handler" {
+				t.Errorf("next handler was not executed")
+			}
+		})
+	}
+}
+
+func TestContentTypeHandler(t *testing.T) {
+	acceptedMediaTypes := []string{api.JsonMediaType, api.OctetStreamMediaType}
+
+	nextHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, err := w.Write([]byte("next handler"))
+		require.NoError(t, err)
+	})
+
+	handler := ContentTypeHandler(acceptedMediaTypes)(nextHandler)
+
+	tests := []struct {
+		name               string
+		contentType        string
+		expectedStatusCode int
+		isGet              bool
+	}{
+		{
+			name:               "Accepted Content-Type - application/json",
+			contentType:        api.JsonMediaType,
+			expectedStatusCode: http.StatusOK,
+		},
+		{
+			name:               "Accepted Content-Type - ssz format",
+			contentType:        api.OctetStreamMediaType,
+			expectedStatusCode: http.StatusOK,
+		},
+		{
+			name:               "Unsupported Content-Type - text/plain",
+			contentType:        "text/plain",
+			expectedStatusCode: http.StatusUnsupportedMediaType,
+		},
+		{
+			name:               "Missing Content-Type",
+			contentType:        "",
+			expectedStatusCode: http.StatusUnsupportedMediaType,
+		},
+		{
+			name:               "GET request skips content type check",
+			contentType:        "",
+			expectedStatusCode: http.StatusOK,
+			isGet:              true,
+		},
+		{
+			name:               "Content type contains charset is ok",
+			contentType:        "application/json; charset=utf-8",
+			expectedStatusCode: http.StatusOK,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			httpMethod := http.MethodPost
+			if tt.isGet {
+				httpMethod = http.MethodGet
+			}
+			req := httptest.NewRequest(httpMethod, "/", nil)
+			if tt.contentType != "" {
+				req.Header.Set("Content-Type", tt.contentType)
+			}
+			rr := httptest.NewRecorder()
+
+			handler.ServeHTTP(rr, req)
+
+			if status := rr.Code; status != tt.expectedStatusCode {
+				t.Errorf("handler returned wrong status code: got %v want %v", status, tt.expectedStatusCode)
+			}
+		})
+	}
+}
+
+func TestAcceptHeaderHandler(t *testing.T) {
+	acceptedTypes := []string{"application/json", "application/octet-stream"}
+
+	nextHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, err := w.Write([]byte("next handler"))
+		require.NoError(t, err)
+	})
+
+	handler := AcceptHeaderHandler(acceptedTypes)(nextHandler)
+
+	tests := []struct {
+		name               string
+		acceptHeader       string
+		expectedStatusCode int
+	}{
+		{
+			name:               "Accepted Accept-Type - application/json",
+			acceptHeader:       "application/json",
+			expectedStatusCode: http.StatusOK,
+		},
+		{
+			name:               "Accepted Accept-Type - application/octet-stream",
+			acceptHeader:       "application/octet-stream",
+			expectedStatusCode: http.StatusOK,
+		},
+		{
+			name:               "Accepted Accept-Type with parameters",
+			acceptHeader:       "application/json;q=0.9, application/octet-stream;q=0.8",
+			expectedStatusCode: http.StatusOK,
+		},
+		{
+			name:               "Unsupported Accept-Type - text/plain",
+			acceptHeader:       "text/plain",
+			expectedStatusCode: http.StatusNotAcceptable,
+		},
+		{
+			name:               "Missing Accept header",
+			acceptHeader:       "",
+			expectedStatusCode: http.StatusOK,
+		},
+		{
+			name:               "*/* is accepted",
+			acceptHeader:       "*/*",
+			expectedStatusCode: http.StatusOK,
+		},
+		{
+			name:               "application/* is accepted",
+			acceptHeader:       "application/*",
+			expectedStatusCode: http.StatusOK,
+		},
+		{
+			name:               "/* is unsupported",
+			acceptHeader:       "/*",
+			expectedStatusCode: http.StatusNotAcceptable,
+		},
+		{
+			name:               "application/ is unsupported",
+			acceptHeader:       "application/",
+			expectedStatusCode: http.StatusNotAcceptable,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := httptest.NewRequest("GET", "/", nil)
+			if tt.acceptHeader != "" {
+				req.Header.Set("Accept", tt.acceptHeader)
+			}
+			rr := httptest.NewRecorder()
+
+			handler.ServeHTTP(rr, req)
+
+			if status := rr.Code; status != tt.expectedStatusCode {
+				t.Errorf("handler returned wrong status code: got %v want %v", status, tt.expectedStatusCode)
+			}
+		})
+	}
+}
--- a/api/server/middleware/util.go
+++ b/api/server/middleware/util.go
@@ -1,4 +1,4 @@
-package server
+package middleware

 import (
 	"net/url"
--- a/api/server/middleware/util_test.go
+++ b/api/server/middleware/util_test.go
@@ -1,4 +1,4 @@
-package server
+package middleware

 import (
 	"testing"
--- a/api/server/middleware_test.go
+++ b/api/server/middleware_test.go
@@ -1,54 +0,0 @@
-package server
-
-import (
-	"net/http"
-	"net/http/httptest"
-	"testing"
-
-	"github.com/prysmaticlabs/prysm/v5/testing/require"
-)
-
-func TestNormalizeQueryValuesHandler(t *testing.T) {
-	nextHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		_, err := w.Write([]byte("next handler"))
-		require.NoError(t, err)
-	})
-
-	handler := NormalizeQueryValuesHandler(nextHandler)
-
-	tests := []struct {
-		name          string
-		inputQuery    string
-		expectedQuery string
-	}{
-		{
-			name:          "3 values",
-			inputQuery:    "key=value1,value2,value3",
-			expectedQuery: "key=value1&key=value2&key=value3", // replace with expected normalized value
-		},
-	}
-
-	for _, test := range tests {
-		t.Run(test.name, func(t *testing.T) {
-			req, err := http.NewRequest("GET", "/test?"+test.inputQuery, nil)
-			if err != nil {
-				t.Fatal(err)
-			}
-
-			rr := httptest.NewRecorder()
-			handler.ServeHTTP(rr, req)
-
-			if rr.Code != http.StatusOK {
-				t.Errorf("handler returned wrong status code: got %v want %v", rr.Code, http.StatusOK)
-			}
-
-			if req.URL.RawQuery != test.expectedQuery {
-				t.Errorf("query not normalized: got %v want %v", req.URL.RawQuery, test.expectedQuery)
-			}
-
-			if rr.Body.String() != "next handler" {
-				t.Errorf("next handler was not executed")
-			}
-		})
-	}
-}
--- a/api/server/structs/BUILD.bazel
+++ b/api/server/structs/BUILD.bazel
@@ -26,6 +26,7 @@ go_library(
        "//api/server:go_default_library",
        "//beacon-chain/state:go_default_library",
        "//config/fieldparams:go_default_library",
+        "//consensus-types/interfaces:go_default_library",
        "//consensus-types/primitives:go_default_library",
        "//consensus-types/validator:go_default_library",
        "//container/slice:go_default_library",
--- a/api/server/structs/block.go
+++ b/api/server/structs/block.go
@@ -1,10 +1,34 @@
 package structs

+import "encoding/json"
+
+// MessageJsoner describes a signed consensus type wrapper that can return the `.Message` field in a json envelope
+// encoded as a []byte, for use as a json.RawMessage value when encoding the outer envelope.
+type MessageJsoner interface {
+	MessageRawJson() ([]byte, error)
+}
+
+// SignedMessageJsoner embeds MessageJsoner and adds a method to also retrieve the Signature field as a string.
+type SignedMessageJsoner interface {
+	MessageJsoner
+	SigString() string
+}
+
 type SignedBeaconBlock struct {
 	Message   *BeaconBlock `json:"message"`
 	Signature string       `json:"signature"`
 }

+var _ SignedMessageJsoner = &SignedBeaconBlock{}
+
+func (s *SignedBeaconBlock) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
+}
+
+func (s *SignedBeaconBlock) SigString() string {
+	return s.Signature
+}
+
 type BeaconBlock struct {
 	Slot          string           `json:"slot"`
 	ProposerIndex string           `json:"proposer_index"`
@@ -29,6 +53,16 @@ type SignedBeaconBlockAltair struct {
 	Signature string             `json:"signature"`
 }

+var _ SignedMessageJsoner = &SignedBeaconBlockAltair{}
+
+func (s *SignedBeaconBlockAltair) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
+}
+
+func (s *SignedBeaconBlockAltair) SigString() string {
+	return s.Signature
+}
+
 type BeaconBlockAltair struct {
 	Slot          string                 `json:"slot"`
 	ProposerIndex string                 `json:"proposer_index"`
@@ -54,6 +88,16 @@ type SignedBeaconBlockBellatrix struct {
 	Signature string                `json:"signature"`
 }

+var _ SignedMessageJsoner = &SignedBeaconBlockBellatrix{}
+
+func (s *SignedBeaconBlockBellatrix) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
+}
+
+func (s *SignedBeaconBlockBellatrix) SigString() string {
+	return s.Signature
+}
+
 type BeaconBlockBellatrix struct {
 	Slot          string                    `json:"slot"`
 	ProposerIndex string                    `json:"proposer_index"`
@@ -80,6 +124,16 @@ type SignedBlindedBeaconBlockBellatrix struct {
 	Signature string                       `json:"signature"`
 }

+var _ SignedMessageJsoner = &SignedBlindedBeaconBlockBellatrix{}
+
+func (s *SignedBlindedBeaconBlockBellatrix) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
+}
+
+func (s *SignedBlindedBeaconBlockBellatrix) SigString() string {
+	return s.Signature
+}
+
 type BlindedBeaconBlockBellatrix struct {
 	Slot          string                           `json:"slot"`
 	ProposerIndex string                           `json:"proposer_index"`
@@ -106,6 +160,16 @@ type SignedBeaconBlockCapella struct {
 	Signature string              `json:"signature"`
 }

+var _ SignedMessageJsoner = &SignedBeaconBlockCapella{}
+
+func (s *SignedBeaconBlockCapella) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
+}
+
+func (s *SignedBeaconBlockCapella) SigString() string {
+	return s.Signature
+}
+
 type BeaconBlockCapella struct {
 	Slot          string                  `json:"slot"`
 	ProposerIndex string                  `json:"proposer_index"`
@@ -133,6 +197,16 @@ type SignedBlindedBeaconBlockCapella struct {
 	Signature string                     `json:"signature"`
 }

+var _ SignedMessageJsoner = &SignedBlindedBeaconBlockCapella{}
+
+func (s *SignedBlindedBeaconBlockCapella) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
+}
+
+func (s *SignedBlindedBeaconBlockCapella) SigString() string {
+	return s.Signature
+}
+
 type BlindedBeaconBlockCapella struct {
 	Slot          string                         `json:"slot"`
 	ProposerIndex string                         `json:"proposer_index"`
@@ -172,6 +246,16 @@ type SignedBeaconBlockDeneb struct {
 	Signature string            `json:"signature"`
 }

+var _ SignedMessageJsoner = &SignedBeaconBlockDeneb{}
+
+func (s *SignedBeaconBlockDeneb) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
+}
+
+func (s *SignedBeaconBlockDeneb) SigString() string {
+	return s.Signature
+}
+
 type BeaconBlockDeneb struct {
 	Slot          string                `json:"slot"`
 	ProposerIndex string                `json:"proposer_index"`
@@ -208,6 +292,16 @@ type SignedBlindedBeaconBlockDeneb struct {
 	Signature string                   `json:"signature"`
 }

+var _ SignedMessageJsoner = &SignedBlindedBeaconBlockDeneb{}
+
+func (s *SignedBlindedBeaconBlockDeneb) MessageRawJson() ([]byte, error) {
+	return json.Marshal(s.Message)
+}
+
+func (s *SignedBlindedBeaconBlockDeneb) SigString() string {
+	return s.Signature
+}
+
 type BlindedBeaconBlockBodyDeneb struct {
 	RandaoReveal           string                        `json:"randao_reveal"`
 	Eth1Data               *Eth1Data                     `json:"eth1_data"`
--- a/api/server/structs/conversions.go
+++ b/api/server/structs/conversions.go
@@ -8,11 +8,10 @@ import (
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/api/server"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/validator"
-	"github.com/prysmaticlabs/prysm/v5/container/slice"
-
 	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/validator"
+	"github.com/prysmaticlabs/prysm/v5/container/slice"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/v5/math"
 	enginev1 "github.com/prysmaticlabs/prysm/v5/proto/engine/v1"
--- a/api/server/structs/conversions_block.go
+++ b/api/server/structs/conversions_block.go
@@ -6,8 +6,10 @@ import (

 	"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"
@@ -15,6 +17,8 @@ import (
 	eth "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 )

+var ErrUnsupportedConversion = errors.New("Could not determine api struct type to use for value")
+
 func (h *SignedBeaconBlockHeader) ToConsensus() (*eth.SignedBeaconBlockHeader, error) {
 	msg, err := h.Message.ToConsensus()
 	if err != nil {
@@ -1852,7 +1856,34 @@ func BeaconBlockFromConsensus(b *eth.BeaconBlock) *BeaconBlock {
 	}
 }

-func SignedBeaconBlockFromConsensus(b *eth.SignedBeaconBlock) *SignedBeaconBlock {
+func SignedBeaconBlockMessageJsoner(block interfaces.ReadOnlySignedBeaconBlock) (SignedMessageJsoner, error) {
+	pb, err := block.Proto()
+	if err != nil {
+		return nil, err
+	}
+	switch pbStruct := pb.(type) {
+	case *eth.SignedBeaconBlock:
+		return SignedBeaconBlockPhase0FromConsensus(pbStruct), nil
+	case *eth.SignedBeaconBlockAltair:
+		return SignedBeaconBlockAltairFromConsensus(pbStruct), nil
+	case *eth.SignedBlindedBeaconBlockBellatrix:
+		return SignedBlindedBeaconBlockBellatrixFromConsensus(pbStruct)
+	case *eth.SignedBeaconBlockBellatrix:
+		return SignedBeaconBlockBellatrixFromConsensus(pbStruct)
+	case *eth.SignedBlindedBeaconBlockCapella:
+		return SignedBlindedBeaconBlockCapellaFromConsensus(pbStruct)
+	case *eth.SignedBeaconBlockCapella:
+		return SignedBeaconBlockCapellaFromConsensus(pbStruct)
+	case *eth.SignedBlindedBeaconBlockDeneb:
+		return SignedBlindedBeaconBlockDenebFromConsensus(pbStruct)
+	case *eth.SignedBeaconBlockDeneb:
+		return SignedBeaconBlockDenebFromConsensus(pbStruct)
+	default:
+		return nil, ErrUnsupportedConversion
+	}
+}
+
+func SignedBeaconBlockPhase0FromConsensus(b *eth.SignedBeaconBlock) *SignedBeaconBlock {
 	return &SignedBeaconBlock{
 		Message:   BeaconBlockFromConsensus(b.Block),
 		Signature: hexutil.Encode(b.Signature),
--- a/async/abool/abool_test.go
+++ b/async/abool/abool_test.go
@@ -88,7 +88,7 @@ func TestToggle(t *testing.T) {
 	}
 }

-func TestToogleMultipleTimes(t *testing.T) {
+func TestToggleMultipleTimes(t *testing.T) {
 	t.Parallel()

 	v := New()
@@ -101,16 +101,16 @@ func TestToogleMultipleTimes(t *testing.T) {

 		expected := i%2 != 0
 		if v.IsSet() != expected {
-			t.Fatalf("AtomicBool.Toogle() doesn't work after %d calls, expected: %v, got %v", i, expected, v.IsSet())
+			t.Fatalf("AtomicBool.Toggle() doesn't work after %d calls, expected: %v, got %v", i, expected, v.IsSet())
 		}

 		if pre == v.IsSet() {
-			t.Fatalf("AtomicBool.Toogle() returned wrong value at the %dth calls, expected: %v, got %v", i, !v.IsSet(), pre)
+			t.Fatalf("AtomicBool.Toggle() returned wrong value at the %dth calls, expected: %v, got %v", i, !v.IsSet(), pre)
 		}
 	}
 }

-func TestToogleAfterOverflow(t *testing.T) {
+func TestToggleAfterOverflow(t *testing.T) {
 	t.Parallel()

 	var value int32 = math.MaxInt32
@@ -122,7 +122,7 @@ func TestToogleAfterOverflow(t *testing.T) {
 	v.Toggle()
 	expected := math.MaxInt32%2 == 0
 	if v.IsSet() != expected {
-		t.Fatalf("AtomicBool.Toogle() doesn't work after overflow, expected: %v, got %v", expected, v.IsSet())
+		t.Fatalf("AtomicBool.Toggle() doesn't work after overflow, expected: %v, got %v", expected, v.IsSet())
 	}

 	// make sure overflow happened
@@ -135,7 +135,7 @@ func TestToogleAfterOverflow(t *testing.T) {
 	v.Toggle()
 	expected = !expected
 	if v.IsSet() != expected {
-		t.Fatalf("AtomicBool.Toogle() doesn't work after the second call after overflow, expected: %v, got %v", expected, v.IsSet())
+		t.Fatalf("AtomicBool.Toggle() doesn't work after the second call after overflow, expected: %v, got %v", expected, v.IsSet())
 	}
 }

--- a/async/event/feed.go
+++ b/async/event/feed.go
@@ -20,6 +20,7 @@ package event
 import (
 	"errors"
 	"reflect"
+	"slices"
 	"sync"
 )

@@ -219,12 +220,9 @@ type caseList []reflect.SelectCase

 // find returns the index of a case containing the given channel.
 func (cs caseList) find(channel interface{}) int {
-	for i, cas := range cs {
-		if cas.Chan.Interface() == channel {
-			return i
-		}
-	}
-	return -1
+	return slices.IndexFunc(cs, func(selectCase reflect.SelectCase) bool {
+		return selectCase.Chan.Interface() == channel
+	})
 }

 // delete removes the given case from cs.
--- a/async/scatter.go
+++ b/async/scatter.go
@@ -63,7 +63,7 @@ func Scatter(inputLen int, sFunc func(int, int, *sync.RWMutex) (interface{}, err
 	return results, nil
 }

-// calculateChunkSize calculates a suitable chunk size for the purposes of parallelisation.
+// calculateChunkSize calculates a suitable chunk size for the purposes of parallelization.
 func calculateChunkSize(items int) int {
 	// Start with a simple even split
 	chunkSize := items / runtime.GOMAXPROCS(0)
--- a/bazel.sh
+++ b/bazel.sh
@@ -2,7 +2,7 @@

 # This script serves as a wrapper around bazel to limit the scope of environment variables that
 # may change the action output. Using this script should result in a higher cache hit ratio for
-# cached actions with a more heremtic build.
+# cached actions with a more hermetic build.

 env -i \
 PATH=/usr/bin:/bin \
--- a/beacon-chain/blockchain/BUILD.bazel
+++ b/beacon-chain/blockchain/BUILD.bazel
@@ -64,6 +64,7 @@ go_library(
        "//beacon-chain/operations/slashings:go_default_library",
        "//beacon-chain/operations/voluntaryexits:go_default_library",
        "//beacon-chain/p2p:go_default_library",
+        "//beacon-chain/slasher/types:go_default_library",
        "//beacon-chain/startup:go_default_library",
        "//beacon-chain/state:go_default_library",
        "//beacon-chain/state/stategen:go_default_library",
@@ -137,7 +138,8 @@ go_test(
        "//async/event:go_default_library",
        "//beacon-chain/blockchain/testing:go_default_library",
        "//beacon-chain/cache:go_default_library",
-        "//beacon-chain/cache/depositcache:go_default_library",
+        "//beacon-chain/cache/depositsnapshot:go_default_library",
+        "//beacon-chain/core/altair:go_default_library",
        "//beacon-chain/core/blocks:go_default_library",
        "//beacon-chain/core/feed/state:go_default_library",
        "//beacon-chain/core/helpers:go_default_library",
@@ -181,6 +183,7 @@ go_test(
        "//time:go_default_library",
        "//time/slots:go_default_library",
        "@com_github_ethereum_go_ethereum//common:go_default_library",
+        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
        "@com_github_ethereum_go_ethereum//core/types:go_default_library",
        "@com_github_holiman_uint256//:go_default_library",
        "@com_github_pkg_errors//:go_default_library",
--- a/beacon-chain/blockchain/chain_info.go
+++ b/beacon-chain/blockchain/chain_info.go
@@ -6,12 +6,9 @@ import (
 	"time"

 	"github.com/pkg/errors"
-	"go.opencensus.io/trace"
-
 	"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"
-	forkchoicetypes "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/types"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
@@ -21,6 +18,7 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
+	"go.opencensus.io/trace"
 )

 // ChainInfoFetcher defines a common interface for methods in blockchain service which
@@ -399,14 +397,6 @@ func (s *Service) InForkchoice(root [32]byte) bool {
 	return s.cfg.ForkChoiceStore.HasNode(root)
 }

-// IsViableForCheckpoint returns whether the given checkpoint is a checkpoint in any
-// chain known to forkchoice
-func (s *Service) IsViableForCheckpoint(cp *forkchoicetypes.Checkpoint) (bool, error) {
-	s.cfg.ForkChoiceStore.RLock()
-	defer s.cfg.ForkChoiceStore.RUnlock()
-	return s.cfg.ForkChoiceStore.IsViableForCheckpoint(cp)
-}
-
 // IsOptimisticForRoot takes the root as argument instead of the current head
 // and returns true if it is optimistic.
 func (s *Service) IsOptimisticForRoot(ctx context.Context, root [32]byte) (bool, error) {
@@ -518,13 +508,6 @@ func (s *Service) Ancestor(ctx context.Context, root []byte, slot primitives.Slo
 	return ar[:], nil
 }

-// SetOptimisticToInvalid wraps the corresponding method in forkchoice
-func (s *Service) SetOptimisticToInvalid(ctx context.Context, root, parent, lvh [32]byte) ([][32]byte, error) {
-	s.cfg.ForkChoiceStore.Lock()
-	defer s.cfg.ForkChoiceStore.Unlock()
-	return s.cfg.ForkChoiceStore.SetOptimisticToInvalid(ctx, root, parent, lvh)
-}
-
 // SetGenesisTime sets the genesis time of beacon chain.
 func (s *Service) SetGenesisTime(t time.Time) {
 	s.genesisTime = t
@@ -563,3 +546,9 @@ func (s *Service) RecentBlockSlot(root [32]byte) (primitives.Slot, error) {
 func (s *Service) inRegularSync() bool {
 	return s.cfg.SyncChecker.Synced()
 }
+
+// validating returns true if the beacon is tracking some validators that have
+// registered for proposing.
+func (s *Service) validating() bool {
+	return s.cfg.TrackedValidatorsCache.Validating()
+}
--- a/beacon-chain/blockchain/execution_engine.go
+++ b/beacon-chain/blockchain/execution_engine.go
@@ -74,8 +74,8 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *fcuConfig) (*
 	}
 	payloadID, lastValidHash, err := s.cfg.ExecutionEngineCaller.ForkchoiceUpdated(ctx, fcs, arg.attributes)
 	if err != nil {
-		switch err {
-		case execution.ErrAcceptedSyncingPayloadStatus:
+		switch {
+		case errors.Is(err, execution.ErrAcceptedSyncingPayloadStatus):
 			forkchoiceUpdatedOptimisticNodeCount.Inc()
 			log.WithFields(logrus.Fields{
 				"headSlot":                  headBlk.Slot(),
@@ -83,7 +83,7 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *fcuConfig) (*
 				"finalizedPayloadBlockHash": fmt.Sprintf("%#x", bytesutil.Trunc(finalizedHash[:])),
 			}).Info("Called fork choice updated with optimistic block")
 			return payloadID, nil
-		case execution.ErrInvalidPayloadStatus:
+		case errors.Is(err, execution.ErrInvalidPayloadStatus):
 			forkchoiceUpdatedInvalidNodeCount.Inc()
 			headRoot := arg.headRoot
 			if len(lastValidHash) == 0 {
@@ -139,7 +139,6 @@ func (s *Service) notifyForkchoiceUpdate(ctx context.Context, arg *fcuConfig) (*
 				"newHeadRoot":          fmt.Sprintf("%#x", bytesutil.Trunc(r[:])),
 			}).Warn("Pruned invalid blocks")
 			return pid, invalidBlock{error: ErrInvalidPayload, root: arg.headRoot, invalidAncestorRoots: invalidRoots}
-
 		default:
 			log.WithError(err).Error(ErrUndefinedExecutionEngineError)
 			return nil, nil
@@ -231,18 +230,18 @@ func (s *Service) notifyNewPayload(ctx context.Context, preStateVersion int,
 	} else {
 		lastValidHash, err = s.cfg.ExecutionEngineCaller.NewPayload(ctx, payload, []common.Hash{}, &common.Hash{} /*empty version hashes and root before Deneb*/)
 	}
-	switch err {
-	case nil:
+	switch {
+	case err == nil:
 		newPayloadValidNodeCount.Inc()
 		return true, nil
-	case execution.ErrAcceptedSyncingPayloadStatus:
+	case errors.Is(err, execution.ErrAcceptedSyncingPayloadStatus):
 		newPayloadOptimisticNodeCount.Inc()
 		log.WithFields(logrus.Fields{
 			"slot":             blk.Block().Slot(),
 			"payloadBlockHash": fmt.Sprintf("%#x", bytesutil.Trunc(payload.BlockHash())),
 		}).Info("Called new payload with optimistic block")
 		return false, nil
-	case execution.ErrInvalidPayloadStatus:
+	case errors.Is(err, execution.ErrInvalidPayloadStatus):
 		lvh := bytesutil.ToBytes32(lastValidHash)
 		return false, invalidBlock{
 			error:         ErrInvalidPayload,
@@ -256,7 +255,7 @@ func (s *Service) notifyNewPayload(ctx context.Context, preStateVersion int,
 // reportInvalidBlock deals with the event that an invalid block was detected by the execution layer
 func (s *Service) pruneInvalidBlock(ctx context.Context, root, parentRoot, lvh [32]byte) error {
 	newPayloadInvalidNodeCount.Inc()
-	invalidRoots, err := s.SetOptimisticToInvalid(ctx, root, parentRoot, lvh)
+	invalidRoots, err := s.cfg.ForkChoiceStore.SetOptimisticToInvalid(ctx, root, parentRoot, lvh)
 	if err != nil {
 		return err
 	}
@@ -325,7 +324,7 @@ func (s *Service) getPayloadAttribute(ctx context.Context, st state.BeaconState,
 	var attr payloadattribute.Attributer
 	switch st.Version() {
 	case version.Deneb:
-		withdrawals, err := st.ExpectedWithdrawals()
+		withdrawals, _, err := st.ExpectedWithdrawals()
 		if err != nil {
 			log.WithError(err).Error("Could not get expected withdrawals to get payload attribute")
 			return emptyAttri
@@ -342,7 +341,7 @@ func (s *Service) getPayloadAttribute(ctx context.Context, st state.BeaconState,
 			return emptyAttri
 		}
 	case version.Capella:
-		withdrawals, err := st.ExpectedWithdrawals()
+		withdrawals, _, err := st.ExpectedWithdrawals()
 		if err != nil {
 			log.WithError(err).Error("Could not get expected withdrawals to get payload attribute")
 			return emptyAttri
--- a/beacon-chain/blockchain/head.go
+++ b/beacon-chain/blockchain/head.go
@@ -401,7 +401,7 @@ func (s *Service) saveOrphanedOperations(ctx context.Context, orphanedRoot [32]b
 		}
 		for _, a := range orphanedBlk.Block().Body().Attestations() {
 			// if the attestation is one epoch older, it wouldn't been useful to save it.
-			if a.Data.Slot+params.BeaconConfig().SlotsPerEpoch < s.CurrentSlot() {
+			if a.GetData().Slot+params.BeaconConfig().SlotsPerEpoch < s.CurrentSlot() {
 				continue
 			}
 			if helpers.IsAggregated(a) {
--- a/beacon-chain/blockchain/head_sync_committee_info_test.go
+++ b/beacon-chain/blockchain/head_sync_committee_info_test.go
@@ -61,7 +61,7 @@ func TestService_headNextSyncCommitteeIndices(t *testing.T) {
 	indices, err := c.headNextSyncCommitteeIndices(context.Background(), 0, primitives.Slot(slot))
 	require.NoError(t, err)

-	// NextSyncCommittee should be be empty after `ProcessSyncCommitteeUpdates`. Validator should get indices.
+	// NextSyncCommittee should be empty after `ProcessSyncCommitteeUpdates`. Validator should get indices.
 	require.NotEqual(t, 0, len(indices))
 }

--- a/beacon-chain/blockchain/head_test.go
+++ b/beacon-chain/blockchain/head_test.go
@@ -312,14 +312,14 @@ func TestSaveOrphanedAtts(t *testing.T) {

 	require.NoError(t, service.saveOrphanedOperations(ctx, r3, r4))
 	require.Equal(t, 3, service.cfg.AttPool.AggregatedAttestationCount())
-	wantAtts := []*ethpb.Attestation{
+	wantAtts := []ethpb.Att{
 		blk3.Block.Body.Attestations[0],
 		blk2.Block.Body.Attestations[0],
 		blk1.Block.Body.Attestations[0],
 	}
 	atts := service.cfg.AttPool.AggregatedAttestations()
 	sort.Slice(atts, func(i, j int) bool {
-		return atts[i].Data.Slot > atts[j].Data.Slot
+		return atts[i].GetData().Slot > atts[j].GetData().Slot
 	})
 	require.DeepEqual(t, wantAtts, atts)
 }
@@ -389,14 +389,14 @@ func TestSaveOrphanedOps(t *testing.T) {

 	require.NoError(t, service.saveOrphanedOperations(ctx, r3, r4))
 	require.Equal(t, 3, service.cfg.AttPool.AggregatedAttestationCount())
-	wantAtts := []*ethpb.Attestation{
+	wantAtts := []ethpb.Att{
 		blk3.Block.Body.Attestations[0],
 		blk2.Block.Body.Attestations[0],
 		blk1.Block.Body.Attestations[0],
 	}
 	atts := service.cfg.AttPool.AggregatedAttestations()
 	sort.Slice(atts, func(i, j int) bool {
-		return atts[i].Data.Slot > atts[j].Data.Slot
+		return atts[i].GetData().Slot > atts[j].GetData().Slot
 	})
 	require.DeepEqual(t, wantAtts, atts)
 	require.Equal(t, 1, len(service.cfg.SlashingPool.PendingProposerSlashings(ctx, st, false)))
@@ -517,14 +517,14 @@ func TestSaveOrphanedAtts_DoublyLinkedTrie(t *testing.T) {

 	require.NoError(t, service.saveOrphanedOperations(ctx, r3, r4))
 	require.Equal(t, 3, service.cfg.AttPool.AggregatedAttestationCount())
-	wantAtts := []*ethpb.Attestation{
+	wantAtts := []ethpb.Att{
 		blk3.Block.Body.Attestations[0],
 		blk2.Block.Body.Attestations[0],
 		blk1.Block.Body.Attestations[0],
 	}
 	atts := service.cfg.AttPool.AggregatedAttestations()
 	sort.Slice(atts, func(i, j int) bool {
-		return atts[i].Data.Slot > atts[j].Data.Slot
+		return atts[i].GetData().Slot > atts[j].GetData().Slot
 	})
 	require.DeepEqual(t, wantAtts, atts)
 }
--- a/beacon-chain/blockchain/lightclient.go
+++ b/beacon-chain/blockchain/lightclient.go
@@ -69,7 +69,7 @@ func NewLightClientOptimisticUpdateFromBeaconState(
 	// assert sum(block.message.body.sync_aggregate.sync_committee_bits) >= MIN_SYNC_COMMITTEE_PARTICIPANTS
 	syncAggregate, err := block.Block().Body().SyncAggregate()
 	if err != nil {
-		return nil, fmt.Errorf("could not get sync aggregate %v", err)
+		return nil, fmt.Errorf("could not get sync aggregate %w", err)
 	}

 	if syncAggregate.SyncCommitteeBits.Count() < params.BeaconConfig().MinSyncCommitteeParticipants {
@@ -85,18 +85,18 @@ func NewLightClientOptimisticUpdateFromBeaconState(
 	header := state.LatestBlockHeader()
 	stateRoot, err := state.HashTreeRoot(ctx)
 	if err != nil {
-		return nil, fmt.Errorf("could not get state root %v", err)
+		return nil, fmt.Errorf("could not get state root %w", err)
 	}
 	header.StateRoot = stateRoot[:]

 	headerRoot, err := header.HashTreeRoot()
 	if err != nil {
-		return nil, fmt.Errorf("could not get header root %v", err)
+		return nil, fmt.Errorf("could not get header root %w", err)
 	}

 	blockRoot, err := block.Block().HashTreeRoot()
 	if err != nil {
-		return nil, fmt.Errorf("could not get block root %v", err)
+		return nil, fmt.Errorf("could not get block root %w", err)
 	}

 	if headerRoot != blockRoot {
@@ -114,14 +114,14 @@ func NewLightClientOptimisticUpdateFromBeaconState(
 	// attested_header.state_root = hash_tree_root(attested_state)
 	attestedStateRoot, err := attestedState.HashTreeRoot(ctx)
 	if err != nil {
-		return nil, fmt.Errorf("could not get attested state root %v", err)
+		return nil, fmt.Errorf("could not get attested state root %w", err)
 	}
 	attestedHeader.StateRoot = attestedStateRoot[:]

 	// assert hash_tree_root(attested_header) == block.message.parent_root
 	attestedHeaderRoot, err := attestedHeader.HashTreeRoot()
 	if err != nil {
-		return nil, fmt.Errorf("could not get attested header root %v", err)
+		return nil, fmt.Errorf("could not get attested header root %w", err)
 	}

 	if attestedHeaderRoot != block.Block().ParentRoot() {
@@ -175,13 +175,13 @@ func NewLightClientFinalityUpdateFromBeaconState(
 		if finalizedBlock.Block().Slot() != 0 {
 			tempFinalizedHeader, err := finalizedBlock.Header()
 			if err != nil {
-				return nil, fmt.Errorf("could not get finalized header %v", err)
+				return nil, fmt.Errorf("could not get finalized header %w", err)
 			}
 			finalizedHeader = migration.V1Alpha1SignedHeaderToV1(tempFinalizedHeader).GetMessage()

 			finalizedHeaderRoot, err := finalizedHeader.HashTreeRoot()
 			if err != nil {
-				return nil, fmt.Errorf("could not get finalized header root %v", err)
+				return nil, fmt.Errorf("could not get finalized header root %w", err)
 			}

 			if finalizedHeaderRoot != bytesutil.ToBytes32(attestedState.FinalizedCheckpoint().Root) {
@@ -204,7 +204,7 @@ func NewLightClientFinalityUpdateFromBeaconState(
 		var bErr error
 		finalityBranch, bErr = attestedState.FinalizedRootProof(ctx)
 		if bErr != nil {
-			return nil, fmt.Errorf("could not get finalized root proof %v", bErr)
+			return nil, fmt.Errorf("could not get finalized root proof %w", bErr)
 		}
 	} else {
 		finalizedHeader = &ethpbv1.BeaconBlockHeader{
--- a/beacon-chain/blockchain/log.go
+++ b/beacon-chain/blockchain/log.go
@@ -82,19 +82,20 @@ func logBlockSyncStatus(block interfaces.ReadOnlyBeaconBlock, blockRoot [32]byte
 	if level >= logrus.DebugLevel {
 		parentRoot := block.ParentRoot()
 		lf := logrus.Fields{
-			"slot":                      block.Slot(),
-			"slotInEpoch":               block.Slot() % params.BeaconConfig().SlotsPerEpoch,
-			"block":                     fmt.Sprintf("0x%s...", hex.EncodeToString(blockRoot[:])[:8]),
-			"epoch":                     slots.ToEpoch(block.Slot()),
-			"justifiedEpoch":            justified.Epoch,
-			"justifiedRoot":             fmt.Sprintf("0x%s...", hex.EncodeToString(justified.Root)[:8]),
-			"finalizedEpoch":            finalized.Epoch,
-			"finalizedRoot":             fmt.Sprintf("0x%s...", hex.EncodeToString(finalized.Root)[:8]),
-			"parentRoot":                fmt.Sprintf("0x%s...", hex.EncodeToString(parentRoot[:])[:8]),
-			"version":                   version.String(block.Version()),
-			"sinceSlotStartTime":        prysmTime.Now().Sub(startTime),
-			"chainServiceProcessedTime": prysmTime.Now().Sub(receivedTime) - daWaitedTime,
-			"deposits":                  len(block.Body().Deposits()),
+			"slot":                       block.Slot(),
+			"slotInEpoch":                block.Slot() % params.BeaconConfig().SlotsPerEpoch,
+			"block":                      fmt.Sprintf("0x%s...", hex.EncodeToString(blockRoot[:])[:8]),
+			"epoch":                      slots.ToEpoch(block.Slot()),
+			"justifiedEpoch":             justified.Epoch,
+			"justifiedRoot":              fmt.Sprintf("0x%s...", hex.EncodeToString(justified.Root)[:8]),
+			"finalizedEpoch":             finalized.Epoch,
+			"finalizedRoot":              fmt.Sprintf("0x%s...", hex.EncodeToString(finalized.Root)[:8]),
+			"parentRoot":                 fmt.Sprintf("0x%s...", hex.EncodeToString(parentRoot[:])[:8]),
+			"version":                    version.String(block.Version()),
+			"sinceSlotStartTime":         prysmTime.Now().Sub(startTime),
+			"chainServiceProcessedTime":  prysmTime.Now().Sub(receivedTime) - daWaitedTime,
+			"dataAvailabilityWaitedTime": daWaitedTime,
+			"deposits":                   len(block.Body().Deposits()),
 		}
 		log.WithFields(lf).Debug("Synced new block")
 	} else {
--- a/beacon-chain/blockchain/metrics.go
+++ b/beacon-chain/blockchain/metrics.go
@@ -369,6 +369,6 @@ func reportEpochMetrics(ctx context.Context, postState, headState state.BeaconSt

 func reportAttestationInclusion(blk interfaces.ReadOnlyBeaconBlock) {
 	for _, att := range blk.Body().Attestations() {
-		attestationInclusionDelay.Observe(float64(blk.Slot() - att.Data.Slot))
+		attestationInclusionDelay.Observe(float64(blk.Slot() - att.GetData().Slot))
 	}
 }
--- a/beacon-chain/blockchain/pow_block_test.go
+++ b/beacon-chain/blockchain/pow_block_test.go
@@ -163,7 +163,7 @@ func Test_getBlkParentHashAndTD(t *testing.T) {
 	parentHash, totalDifficulty, err := service.getBlkParentHashAndTD(ctx, h[:])
 	require.NoError(t, err)
 	require.Equal(t, p, bytesutil.ToBytes32(parentHash))
-	require.Equal(t, td, totalDifficulty.String())
+	require.Equal(t, td, totalDifficulty.Hex())

 	_, _, err = service.getBlkParentHashAndTD(ctx, []byte{'c'})
 	require.ErrorContains(t, "could not get pow block: block not found", err)
--- a/beacon-chain/blockchain/process_attestation.go
+++ b/beacon-chain/blockchain/process_attestation.go
@@ -36,17 +36,17 @@ import (
 //
 //	 # Update latest messages for attesting indices
 //	 update_latest_messages(store, indexed_attestation.attesting_indices, attestation)
-func (s *Service) OnAttestation(ctx context.Context, a *ethpb.Attestation, disparity time.Duration) error {
+func (s *Service) OnAttestation(ctx context.Context, a ethpb.Att, disparity time.Duration) error {
 	ctx, span := trace.StartSpan(ctx, "blockChain.onAttestation")
 	defer span.End()

 	if err := helpers.ValidateNilAttestation(a); err != nil {
 		return err
 	}
-	if err := helpers.ValidateSlotTargetEpoch(a.Data); err != nil {
+	if err := helpers.ValidateSlotTargetEpoch(a.GetData()); err != nil {
 		return err
 	}
-	tgt := ethpb.CopyCheckpoint(a.Data.Target)
+	tgt := ethpb.CopyCheckpoint(a.GetData().Target)

 	// Note that target root check is ignored here because it was performed in sync's validation pipeline:
 	// validate_aggregate_proof.go and validate_beacon_attestation.go
@@ -67,7 +67,7 @@ func (s *Service) OnAttestation(ctx context.Context, a *ethpb.Attestation, dispa
 	}

 	// Verify attestation beacon block is known and not from the future.
-	if err := s.verifyBeaconBlock(ctx, a.Data); err != nil {
+	if err := s.verifyBeaconBlock(ctx, a.GetData()); err != nil {
 		return errors.Wrap(err, "could not verify attestation beacon block")
 	}

@@ -75,16 +75,16 @@ func (s *Service) OnAttestation(ctx context.Context, a *ethpb.Attestation, dispa
 	// validate_aggregate_proof.go and validate_beacon_attestation.go

 	// Verify attestations can only affect the fork choice of subsequent slots.
-	if err := slots.VerifyTime(genesisTime, a.Data.Slot+1, disparity); err != nil {
+	if err := slots.VerifyTime(genesisTime, a.GetData().Slot+1, disparity); err != nil {
 		return err
 	}

 	// Use the target state to verify attesting indices are valid.
-	committee, err := helpers.BeaconCommitteeFromState(ctx, baseState, a.Data.Slot, a.Data.CommitteeIndex)
+	committees, err := helpers.AttestationCommittees(ctx, baseState, a)
 	if err != nil {
 		return err
 	}
-	indexedAtt, err := attestation.ConvertToIndexed(ctx, a, committee)
+	indexedAtt, err := attestation.ConvertToIndexed(ctx, a, committees...)
 	if err != nil {
 		return err
 	}
@@ -97,7 +97,7 @@ func (s *Service) OnAttestation(ctx context.Context, a *ethpb.Attestation, dispa
 	// We assume trusted attestation in this function has verified signature.

 	// Update forkchoice store with the new attestation for updating weight.
-	s.cfg.ForkChoiceStore.ProcessAttestation(ctx, indexedAtt.AttestingIndices, bytesutil.ToBytes32(a.Data.BeaconBlockRoot), a.Data.Target.Epoch)
+	s.cfg.ForkChoiceStore.ProcessAttestation(ctx, indexedAtt.GetAttestingIndices(), bytesutil.ToBytes32(a.GetData().BeaconBlockRoot), a.GetData().Target.Epoch)

 	return nil
 }
--- a/beacon-chain/blockchain/process_attestation_helpers.go
+++ b/beacon-chain/blockchain/process_attestation_helpers.go
@@ -18,17 +18,63 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
 )

+func (s *Service) getRecentPreState(ctx context.Context, c *ethpb.Checkpoint) state.ReadOnlyBeaconState {
+	headEpoch := slots.ToEpoch(s.HeadSlot())
+	if c.Epoch < headEpoch {
+		return nil
+	}
+	if !s.cfg.ForkChoiceStore.IsCanonical([32]byte(c.Root)) {
+		return nil
+	}
+	if c.Epoch == headEpoch {
+		targetSlot, err := s.cfg.ForkChoiceStore.Slot([32]byte(c.Root))
+		if err != nil {
+			return nil
+		}
+		if slots.ToEpoch(targetSlot)+1 < headEpoch {
+			return nil
+		}
+		st, err := s.HeadStateReadOnly(ctx)
+		if err != nil {
+			return nil
+		}
+		return st
+	}
+	slot, err := slots.EpochStart(c.Epoch)
+	if err != nil {
+		return nil
+	}
+	// Try if we have already set the checkpoint cache
+	epochKey := strconv.FormatUint(uint64(c.Epoch), 10 /* base 10 */)
+	lock := async.NewMultilock(string(c.Root) + epochKey)
+	lock.Lock()
+	defer lock.Unlock()
+	cachedState, err := s.checkpointStateCache.StateByCheckpoint(c)
+	if err != nil {
+		return nil
+	}
+	if cachedState != nil && !cachedState.IsNil() {
+		return cachedState
+	}
+	st, err := s.HeadState(ctx)
+	if err != nil {
+		return nil
+	}
+	st, err = transition.ProcessSlotsUsingNextSlotCache(ctx, st, c.Root, slot)
+	if err != nil {
+		return nil
+	}
+	if err := s.checkpointStateCache.AddCheckpointState(c, st); err != nil {
+		return nil
+	}
+	return st
+}
+
 // getAttPreState retrieves the att pre state by either from the cache or the DB.
 func (s *Service) getAttPreState(ctx context.Context, c *ethpb.Checkpoint) (state.ReadOnlyBeaconState, error) {
 	// If the attestation is recent and canonical we can use the head state to compute the shuffling.
-	headEpoch := slots.ToEpoch(s.HeadSlot())
-	if c.Epoch == headEpoch {
-		targetSlot, err := s.cfg.ForkChoiceStore.Slot([32]byte(c.Root))
-		if err == nil && slots.ToEpoch(targetSlot)+1 >= headEpoch {
-			if s.cfg.ForkChoiceStore.IsCanonical([32]byte(c.Root)) {
-				return s.HeadStateReadOnly(ctx)
-			}
-		}
+	if st := s.getRecentPreState(ctx, c); st != nil {
+		return st, nil
 	}
 	// Use a multilock to allow scoped holding of a mutex by a checkpoint root + epoch
 	// allowing us to behave smarter in terms of how this function is used concurrently.
--- a/beacon-chain/blockchain/process_attestation_test.go
+++ b/beacon-chain/blockchain/process_attestation_test.go
@@ -7,9 +7,11 @@ import (
 	"time"

 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/transition"
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	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/crypto/bls"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/testing/assert"
@@ -73,7 +75,7 @@ func TestStore_OnAttestation_ErrorConditions(t *testing.T) {

 	tests := []struct {
 		name      string
-		a         *ethpb.Attestation
+		a         ethpb.Att
 		wantedErr string
 	}{
 		{
@@ -125,25 +127,58 @@ func TestStore_OnAttestation_ErrorConditions(t *testing.T) {
 }

 func TestStore_OnAttestation_Ok_DoublyLinkedTree(t *testing.T) {
-	service, tr := minimalTestService(t)
-	ctx := tr.ctx
+	eval := func(ctx context.Context, service *Service, genesisState state.BeaconState, pks []bls.SecretKey) {
+		service.SetGenesisTime(time.Unix(time.Now().Unix()-int64(params.BeaconConfig().SecondsPerSlot), 0))
+		require.NoError(t, service.saveGenesisData(ctx, genesisState))
+		att, err := util.GenerateAttestations(genesisState, pks, 1, 0, false)
+		require.NoError(t, err)
+		tRoot := bytesutil.ToBytes32(att[0].GetData().Target.Root)
+		copied := genesisState.Copy()
+		copied, err = transition.ProcessSlots(ctx, copied, 1)
+		require.NoError(t, err)
+		require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, copied, tRoot))
+		ojc := &ethpb.Checkpoint{Epoch: 0, Root: tRoot[:]}
+		ofc := &ethpb.Checkpoint{Epoch: 0, Root: tRoot[:]}
+		state, blkRoot, err := prepareForkchoiceState(ctx, 0, tRoot, tRoot, params.BeaconConfig().ZeroHash, ojc, ofc)
+		require.NoError(t, err)
+		require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
+		require.NoError(t, service.OnAttestation(ctx, att[0], 0))
+	}

-	genesisState, pks := util.DeterministicGenesisState(t, 64)
-	service.SetGenesisTime(time.Unix(time.Now().Unix()-int64(params.BeaconConfig().SecondsPerSlot), 0))
-	require.NoError(t, service.saveGenesisData(ctx, genesisState))
-	att, err := util.GenerateAttestations(genesisState, pks, 1, 0, false)
+	t.Run("pre-Electra", func(t *testing.T) {
+		service, tr := minimalTestService(t)
+		ctx := tr.ctx
+		genesisState, pks := util.DeterministicGenesisState(t, 64)
+		eval(ctx, service, genesisState, pks)
+	})
+	t.Run("post-Electra", func(t *testing.T) {
+		service, tr := minimalTestService(t)
+		ctx := tr.ctx
+		genesisState, pks := util.DeterministicGenesisStateElectra(t, 64)
+		eval(ctx, service, genesisState, pks)
+	})
+}
+
+func TestService_GetRecentPreState(t *testing.T) {
+	service, _ := minimalTestService(t)
+	ctx := context.Background()
+
+	s, err := util.NewBeaconState()
 	require.NoError(t, err)
-	tRoot := bytesutil.ToBytes32(att[0].Data.Target.Root)
-	copied := genesisState.Copy()
-	copied, err = transition.ProcessSlots(ctx, copied, 1)
+	ckRoot := bytesutil.PadTo([]byte{'A'}, fieldparams.RootLength)
+	cp0 := &ethpb.Checkpoint{Epoch: 0, Root: ckRoot}
+	err = s.SetFinalizedCheckpoint(cp0)
 	require.NoError(t, err)
-	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, copied, tRoot))
-	ojc := &ethpb.Checkpoint{Epoch: 0, Root: tRoot[:]}
-	ofc := &ethpb.Checkpoint{Epoch: 0, Root: tRoot[:]}
-	state, blkRoot, err := prepareForkchoiceState(ctx, 0, tRoot, tRoot, params.BeaconConfig().ZeroHash, ojc, ofc)
+
+	st, root, err := prepareForkchoiceState(ctx, 31, [32]byte(ckRoot), [32]byte{}, [32]byte{'R'}, cp0, cp0)
 	require.NoError(t, err)
-	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
-	require.NoError(t, service.OnAttestation(ctx, att[0], 0))
+	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, st, root))
+	service.head = &head{
+		root:  [32]byte(ckRoot),
+		state: s,
+		slot:  31,
+	}
+	require.NotNil(t, service.getRecentPreState(ctx, &ethpb.Checkpoint{Epoch: 1, Root: ckRoot}))
 }

 func TestService_GetAttPreState_Concurrency(t *testing.T) {
--- a/beacon-chain/blockchain/process_block.go
+++ b/beacon-chain/blockchain/process_block.go
@@ -6,8 +6,6 @@ import (
 	"time"

 	"github.com/pkg/errors"
-	"go.opencensus.io/trace"
-
 	"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"
@@ -31,6 +29,8 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1/attestation"
 	"github.com/prysmaticlabs/prysm/v5/runtime/version"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
+	"github.com/sirupsen/logrus"
+	"go.opencensus.io/trace"
 )

 // A custom slot deadline for processing state slots in our cache.
@@ -307,16 +307,16 @@ func (s *Service) updateEpochBoundaryCaches(ctx context.Context, st state.Beacon
 	if err := helpers.UpdateProposerIndicesInCache(ctx, st, e); err != nil {
 		return errors.Wrap(err, "could not update proposer index cache")
 	}
-	go func() {
+	go func(ep primitives.Epoch) {
 		// Use a custom deadline here, since this method runs asynchronously.
 		// We ignore the parent method's context and instead create a new one
 		// with a custom deadline, therefore using the background context instead.
 		slotCtx, cancel := context.WithTimeout(context.Background(), slotDeadline)
 		defer cancel()
-		if err := helpers.UpdateCommitteeCache(slotCtx, st, e+1); err != nil {
+		if err := helpers.UpdateCommitteeCache(slotCtx, st, ep+1); err != nil {
 			log.WithError(err).Warn("Could not update committee cache")
 		}
-	}()
+	}(e)
 	// The latest block header is from the previous epoch
 	r, err := st.LatestBlockHeader().HashTreeRoot()
 	if err != nil {
@@ -365,17 +365,17 @@ func (s *Service) handleEpochBoundary(ctx context.Context, slot primitives.Slot,
 func (s *Service) handleBlockAttestations(ctx context.Context, blk interfaces.ReadOnlyBeaconBlock, st state.BeaconState) error {
 	// Feed in block's attestations to fork choice store.
 	for _, a := range blk.Body().Attestations() {
-		committee, err := helpers.BeaconCommitteeFromState(ctx, st, a.Data.Slot, a.Data.CommitteeIndex)
+		committees, err := helpers.AttestationCommittees(ctx, st, a)
 		if err != nil {
 			return err
 		}
-		indices, err := attestation.AttestingIndices(a.AggregationBits, committee)
+		indices, err := attestation.AttestingIndices(a, committees...)
 		if err != nil {
 			return err
 		}
-		r := bytesutil.ToBytes32(a.Data.BeaconBlockRoot)
+		r := bytesutil.ToBytes32(a.GetData().BeaconBlockRoot)
 		if s.cfg.ForkChoiceStore.HasNode(r) {
-			s.cfg.ForkChoiceStore.ProcessAttestation(ctx, indices, r, a.Data.Target.Epoch)
+			s.cfg.ForkChoiceStore.ProcessAttestation(ctx, indices, r, a.GetData().Target.Epoch)
 		} else if err := s.cfg.AttPool.SaveBlockAttestation(a); err != nil {
 			return err
 		}
@@ -386,7 +386,7 @@ func (s *Service) handleBlockAttestations(ctx context.Context, blk interfaces.Re
 // InsertSlashingsToForkChoiceStore inserts attester slashing indices to fork choice store.
 // To call this function, it's caller's responsibility to ensure the slashing object is valid.
 // This function requires a write lock on forkchoice.
-func (s *Service) InsertSlashingsToForkChoiceStore(ctx context.Context, slashings []*ethpb.AttesterSlashing) {
+func (s *Service) InsertSlashingsToForkChoiceStore(ctx context.Context, slashings []ethpb.AttSlashing) {
 	for _, slashing := range slashings {
 		indices := blocks.SlashableAttesterIndices(slashing)
 		for _, index := range indices {
@@ -558,6 +558,20 @@ func (s *Service) isDataAvailable(ctx context.Context, root [32]byte, signed int
 	// The gossip handler for blobs writes the index of each verified blob referencing the given
 	// root to the channel returned by blobNotifiers.forRoot.
 	nc := s.blobNotifiers.forRoot(root)
+
+	// Log for DA checks that cross over into the next slot; helpful for debugging.
+	nextSlot := slots.BeginsAt(signed.Block().Slot()+1, s.genesisTime)
+	// Avoid logging if DA check is called after next slot start.
+	if nextSlot.After(time.Now()) {
+		nst := time.AfterFunc(time.Until(nextSlot), func() {
+			if len(missing) == 0 {
+				return
+			}
+			log.WithFields(daCheckLogFields(root, signed.Block().Slot(), expected, len(missing))).
+				Error("Still waiting for DA check at slot end.")
+		})
+		defer nst.Stop()
+	}
 	for {
 		select {
 		case idx := <-nc:
@@ -571,11 +585,20 @@ func (s *Service) isDataAvailable(ctx context.Context, root [32]byte, signed int
 			s.blobNotifiers.delete(root)
 			return nil
 		case <-ctx.Done():
-			return errors.Wrap(ctx.Err(), "context deadline waiting for blob sidecars")
+			return errors.Wrapf(ctx.Err(), "context deadline waiting for blob sidecars slot: %d, BlockRoot: %#x", block.Slot(), root)
 		}
 	}
 }

+func daCheckLogFields(root [32]byte, slot primitives.Slot, expected, missing int) logrus.Fields {
+	return logrus.Fields{
+		"slot":          slot,
+		"root":          fmt.Sprintf("%#x", root),
+		"blobsExpected": expected,
+		"blobsWaiting":  missing,
+	}
+}
+
 // lateBlockTasks  is called 4 seconds into the slot and performs tasks
 // related to late blocks. It emits a MissedSlot state feed event.
 // It calls FCU and sets the right attributes if we are proposing next slot
--- a/beacon-chain/blockchain/process_block_helpers.go
+++ b/beacon-chain/blockchain/process_block_helpers.go
@@ -7,9 +7,6 @@ import (

 	"github.com/ethereum/go-ethereum/common"
 	"github.com/pkg/errors"
-	"github.com/sirupsen/logrus"
-	"go.opencensus.io/trace"
-
 	"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/transition"
@@ -25,6 +22,8 @@ import (
 	ethpbv2 "github.com/prysmaticlabs/prysm/v5/proto/eth/v2"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
+	"github.com/sirupsen/logrus"
+	"go.opencensus.io/trace"
 )

 // CurrentSlot returns the current slot based on time.
@@ -60,7 +59,7 @@ func (s *Service) getFCUArgsEarlyBlock(cfg *postBlockProcessConfig, fcuArgs *fcu

 // logNonCanonicalBlockReceived prints a message informing that the received
 // block is not the head of the chain. It requires the caller holds a lock on
-// Foprkchoice.
+// Forkchoice.
 func (s *Service) logNonCanonicalBlockReceived(blockRoot [32]byte, headRoot [32]byte) {
 	receivedWeight, err := s.cfg.ForkChoiceStore.Weight(blockRoot)
 	if err != nil {
--- a/beacon-chain/blockchain/process_block_test.go
+++ b/beacon-chain/blockchain/process_block_test.go
@@ -824,7 +824,10 @@ func TestRemoveBlockAttestationsInPool(t *testing.T) {
 	require.NoError(t, service.cfg.BeaconDB.SaveStateSummary(ctx, &ethpb.StateSummary{Root: r[:]}))
 	require.NoError(t, service.cfg.BeaconDB.SaveGenesisBlockRoot(ctx, r))

-	atts := b.Block.Body.Attestations
+	atts := make([]ethpb.Att, len(b.Block.Body.Attestations))
+	for i, a := range b.Block.Body.Attestations {
+		atts[i] = a
+	}
 	require.NoError(t, service.cfg.AttPool.SaveAggregatedAttestations(atts))
 	wsb, err := consensusblocks.NewSignedBeaconBlock(b)
 	require.NoError(t, err)
@@ -1960,68 +1963,130 @@ func TestNoViableHead_Reboot(t *testing.T) {
 }

 func TestOnBlock_HandleBlockAttestations(t *testing.T) {
-	service, tr := minimalTestService(t)
-	ctx := tr.ctx
+	t.Run("pre-Electra", func(t *testing.T) {
+		service, tr := minimalTestService(t)
+		ctx := tr.ctx

-	st, keys := util.DeterministicGenesisState(t, 64)
-	stateRoot, err := st.HashTreeRoot(ctx)
-	require.NoError(t, err, "Could not hash genesis state")
+		st, keys := util.DeterministicGenesisState(t, 64)
+		stateRoot, err := st.HashTreeRoot(ctx)
+		require.NoError(t, err, "Could not hash genesis state")

-	require.NoError(t, service.saveGenesisData(ctx, st))
+		require.NoError(t, service.saveGenesisData(ctx, st))

-	genesis := blocks.NewGenesisBlock(stateRoot[:])
-	wsb, err := consensusblocks.NewSignedBeaconBlock(genesis)
-	require.NoError(t, err)
-	require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb), "Could not save genesis block")
-	parentRoot, err := genesis.Block.HashTreeRoot()
-	require.NoError(t, err, "Could not get signing root")
-	require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, st, parentRoot), "Could not save genesis state")
-	require.NoError(t, service.cfg.BeaconDB.SaveHeadBlockRoot(ctx, parentRoot), "Could not save genesis state")
+		genesis := blocks.NewGenesisBlock(stateRoot[:])
+		wsb, err := consensusblocks.NewSignedBeaconBlock(genesis)
+		require.NoError(t, err)
+		require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, wsb), "Could not save genesis block")
+		parentRoot, err := genesis.Block.HashTreeRoot()
+		require.NoError(t, err, "Could not get signing root")
+		require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, st, parentRoot), "Could not save genesis state")
+		require.NoError(t, service.cfg.BeaconDB.SaveHeadBlockRoot(ctx, parentRoot), "Could not save genesis state")

-	st, err = service.HeadState(ctx)
-	require.NoError(t, err)
-	b, err := util.GenerateFullBlock(st, keys, util.DefaultBlockGenConfig(), 1)
-	require.NoError(t, err)
-	wsb, err = consensusblocks.NewSignedBeaconBlock(b)
-	require.NoError(t, err)
-	root, err := b.Block.HashTreeRoot()
-	require.NoError(t, err)
-	preState, err := service.getBlockPreState(ctx, wsb.Block())
-	require.NoError(t, err)
-	postState, err := service.validateStateTransition(ctx, preState, wsb)
-	require.NoError(t, err)
-	require.NoError(t, service.savePostStateInfo(ctx, root, wsb, postState))
-	require.NoError(t, service.postBlockProcess(&postBlockProcessConfig{ctx, wsb, root, [32]byte{}, postState, false}))
+		st, err = service.HeadState(ctx)
+		require.NoError(t, err)
+		b, err := util.GenerateFullBlock(st, keys, util.DefaultBlockGenConfig(), 1)
+		require.NoError(t, err)
+		wsb, err = consensusblocks.NewSignedBeaconBlock(b)
+		require.NoError(t, err)
+		root, err := b.Block.HashTreeRoot()
+		require.NoError(t, err)
+		preState, err := service.getBlockPreState(ctx, wsb.Block())
+		require.NoError(t, err)
+		postState, err := service.validateStateTransition(ctx, preState, wsb)
+		require.NoError(t, err)
+		require.NoError(t, service.savePostStateInfo(ctx, root, wsb, postState))
+		require.NoError(t, service.postBlockProcess(&postBlockProcessConfig{ctx, wsb, root, [32]byte{}, postState, false}))

-	st, err = service.HeadState(ctx)
-	require.NoError(t, err)
-	b, err = util.GenerateFullBlock(st, keys, util.DefaultBlockGenConfig(), 2)
-	require.NoError(t, err)
-	wsb, err = consensusblocks.NewSignedBeaconBlock(b)
-	require.NoError(t, err)
+		st, err = service.HeadState(ctx)
+		require.NoError(t, err)
+		b, err = util.GenerateFullBlock(st, keys, util.DefaultBlockGenConfig(), 2)
+		require.NoError(t, err)
+		wsb, err = consensusblocks.NewSignedBeaconBlock(b)
+		require.NoError(t, err)

-	// prepare another block that is not inserted
-	st3, err := transition.ExecuteStateTransition(ctx, st, wsb)
-	require.NoError(t, err)
-	b3, err := util.GenerateFullBlock(st3, keys, util.DefaultBlockGenConfig(), 3)
-	require.NoError(t, err)
-	wsb3, err := consensusblocks.NewSignedBeaconBlock(b3)
-	require.NoError(t, err)
+		// prepare another block that is not inserted
+		st3, err := transition.ExecuteStateTransition(ctx, st, wsb)
+		require.NoError(t, err)
+		b3, err := util.GenerateFullBlock(st3, keys, util.DefaultBlockGenConfig(), 3)
+		require.NoError(t, err)
+		wsb3, err := consensusblocks.NewSignedBeaconBlock(b3)
+		require.NoError(t, err)

-	require.Equal(t, 1, len(wsb.Block().Body().Attestations()))
-	a := wsb.Block().Body().Attestations()[0]
-	r := bytesutil.ToBytes32(a.Data.BeaconBlockRoot)
-	require.Equal(t, true, service.cfg.ForkChoiceStore.HasNode(r))
+		require.Equal(t, 1, len(wsb.Block().Body().Attestations()))
+		a := wsb.Block().Body().Attestations()[0]
+		r := bytesutil.ToBytes32(a.GetData().BeaconBlockRoot)
+		require.Equal(t, true, service.cfg.ForkChoiceStore.HasNode(r))

-	require.Equal(t, 1, len(wsb.Block().Body().Attestations()))
-	a3 := wsb3.Block().Body().Attestations()[0]
-	r3 := bytesutil.ToBytes32(a3.Data.BeaconBlockRoot)
-	require.Equal(t, false, service.cfg.ForkChoiceStore.HasNode(r3))
+		require.Equal(t, 1, len(wsb.Block().Body().Attestations()))
+		a3 := wsb3.Block().Body().Attestations()[0]
+		r3 := bytesutil.ToBytes32(a3.GetData().BeaconBlockRoot)
+		require.Equal(t, false, service.cfg.ForkChoiceStore.HasNode(r3))

-	require.NoError(t, service.handleBlockAttestations(ctx, wsb.Block(), st)) // fine to use the same committee as st
-	require.Equal(t, 0, service.cfg.AttPool.ForkchoiceAttestationCount())
-	require.NoError(t, service.handleBlockAttestations(ctx, wsb3.Block(), st3)) // fine to use the same committee as st
-	require.Equal(t, 1, len(service.cfg.AttPool.BlockAttestations()))
+		require.NoError(t, service.handleBlockAttestations(ctx, wsb.Block(), st)) // fine to use the same committee as st
+		require.Equal(t, 0, service.cfg.AttPool.ForkchoiceAttestationCount())
+		require.NoError(t, service.handleBlockAttestations(ctx, wsb3.Block(), st3)) // fine to use the same committee as st
+		require.Equal(t, 1, len(service.cfg.AttPool.BlockAttestations()))
+	})
+	t.Run("post-Electra", func(t *testing.T) {
+		service, tr := minimalTestService(t)
+		ctx := tr.ctx
+
+		st, keys := util.DeterministicGenesisStateElectra(t, 64)
+		require.NoError(t, service.saveGenesisData(ctx, st))
+
+		genesis, err := blocks.NewGenesisBlockForState(ctx, st)
+		require.NoError(t, err)
+		require.NoError(t, service.cfg.BeaconDB.SaveBlock(ctx, genesis), "Could not save genesis block")
+		parentRoot, err := genesis.Block().HashTreeRoot()
+		require.NoError(t, err, "Could not get signing root")
+		require.NoError(t, service.cfg.BeaconDB.SaveState(ctx, st, parentRoot), "Could not save genesis state")
+		require.NoError(t, service.cfg.BeaconDB.SaveHeadBlockRoot(ctx, parentRoot), "Could not save genesis state")
+
+		st, err = service.HeadState(ctx)
+		require.NoError(t, err)
+		b, err := util.GenerateFullBlockElectra(st, keys, util.DefaultBlockGenConfig(), 1)
+		require.NoError(t, err)
+		wsb, err := consensusblocks.NewSignedBeaconBlock(b)
+		require.NoError(t, err)
+		root, err := b.Block.HashTreeRoot()
+		require.NoError(t, err)
+		preState, err := service.getBlockPreState(ctx, wsb.Block())
+		require.NoError(t, err)
+		postState, err := service.validateStateTransition(ctx, preState, wsb)
+		require.NoError(t, err)
+		require.NoError(t, service.savePostStateInfo(ctx, root, wsb, postState))
+		require.NoError(t, service.postBlockProcess(&postBlockProcessConfig{ctx, wsb, root, [32]byte{}, postState, false}))
+
+		st, err = service.HeadState(ctx)
+		require.NoError(t, err)
+		b, err = util.GenerateFullBlockElectra(st, keys, util.DefaultBlockGenConfig(), 2)
+		require.NoError(t, err)
+		wsb, err = consensusblocks.NewSignedBeaconBlock(b)
+		require.NoError(t, err)
+
+		// prepare another block that is not inserted
+		st3, err := transition.ExecuteStateTransition(ctx, st, wsb)
+		require.NoError(t, err)
+		b3, err := util.GenerateFullBlockElectra(st3, keys, util.DefaultBlockGenConfig(), 3)
+		require.NoError(t, err)
+		wsb3, err := consensusblocks.NewSignedBeaconBlock(b3)
+		require.NoError(t, err)
+
+		require.Equal(t, 1, len(wsb.Block().Body().Attestations()))
+		a := wsb.Block().Body().Attestations()[0]
+		r := bytesutil.ToBytes32(a.GetData().BeaconBlockRoot)
+		require.Equal(t, true, service.cfg.ForkChoiceStore.HasNode(r))
+
+		require.Equal(t, 1, len(wsb.Block().Body().Attestations()))
+		a3 := wsb3.Block().Body().Attestations()[0]
+		r3 := bytesutil.ToBytes32(a3.GetData().BeaconBlockRoot)
+		require.Equal(t, false, service.cfg.ForkChoiceStore.HasNode(r3))
+
+		require.NoError(t, service.handleBlockAttestations(ctx, wsb.Block(), st)) // fine to use the same committee as st
+		require.Equal(t, 0, service.cfg.AttPool.ForkchoiceAttestationCount())
+		require.NoError(t, service.handleBlockAttestations(ctx, wsb3.Block(), st3)) // fine to use the same committee as st
+		require.Equal(t, 1, len(service.cfg.AttPool.BlockAttestations()))
+	})
 }

 func TestFillMissingBlockPayloadId_DiffSlotExitEarly(t *testing.T) {
@@ -2115,7 +2180,7 @@ func TestMissingIndices(t *testing.T) {
 	for _, c := range cases {
 		bm, bs := filesystem.NewEphemeralBlobStorageWithMocker(t)
 		t.Run(c.name, func(t *testing.T) {
-			require.NoError(t, bm.CreateFakeIndices(c.root, c.present))
+			require.NoError(t, bm.CreateFakeIndices(c.root, c.present...))
 			missing, err := missingIndices(bs, c.root, c.expected)
 			if c.err != nil {
 				require.ErrorIs(t, err, c.err)
--- a/beacon-chain/blockchain/receive_attestation.go
+++ b/beacon-chain/blockchain/receive_attestation.go
@@ -31,7 +31,7 @@ type AttestationStateFetcher interface {
 // AttestationReceiver interface defines the methods of chain service receive and processing new attestations.
 type AttestationReceiver interface {
 	AttestationStateFetcher
-	VerifyLmdFfgConsistency(ctx context.Context, att *ethpb.Attestation) error
+	VerifyLmdFfgConsistency(ctx context.Context, att ethpb.Att) error
 	InForkchoice([32]byte) bool
 }

@@ -51,13 +51,13 @@ func (s *Service) AttestationTargetState(ctx context.Context, target *ethpb.Chec
 }

 // VerifyLmdFfgConsistency verifies that attestation's LMD and FFG votes are consistency to each other.
-func (s *Service) VerifyLmdFfgConsistency(ctx context.Context, a *ethpb.Attestation) error {
-	r, err := s.TargetRootForEpoch([32]byte(a.Data.BeaconBlockRoot), a.Data.Target.Epoch)
+func (s *Service) VerifyLmdFfgConsistency(ctx context.Context, a ethpb.Att) error {
+	r, err := s.TargetRootForEpoch([32]byte(a.GetData().BeaconBlockRoot), a.GetData().Target.Epoch)
 	if err != nil {
 		return err
 	}
-	if !bytes.Equal(a.Data.Target.Root, r[:]) {
-		return fmt.Errorf("FFG and LMD votes are not consistent, block root: %#x, target root: %#x, canonical target root: %#x", a.Data.BeaconBlockRoot, a.Data.Target.Root, r)
+	if !bytes.Equal(a.GetData().Target.Root, r[:]) {
+		return fmt.Errorf("FFG and LMD votes are not consistent, block root: %#x, target root: %#x, canonical target root: %#x", a.GetData().BeaconBlockRoot, a.GetData().Target.Root, r)
 	}
 	return nil
 }
@@ -95,7 +95,9 @@ func (s *Service) spawnProcessAttestationsRoutine() {
 				return
 			case slotInterval := <-ticker.C():
 				if slotInterval.Interval > 0 {
-					s.UpdateHead(s.ctx, slotInterval.Slot+1)
+					if s.validating() {
+						s.UpdateHead(s.ctx, slotInterval.Slot+1)
+					}
 				} else {
 					s.cfg.ForkChoiceStore.Lock()
 					if err := s.cfg.ForkChoiceStore.NewSlot(s.ctx, slotInterval.Slot); err != nil {
@@ -168,13 +170,13 @@ func (s *Service) processAttestations(ctx context.Context, disparity time.Durati
 		// Based on the spec, don't process the attestation until the subsequent slot.
 		// This delays consideration in the fork choice until their slot is in the past.
 		// https://github.com/ethereum/consensus-specs/blob/dev/specs/phase0/fork-choice.md#validate_on_attestation
-		nextSlot := a.Data.Slot + 1
+		nextSlot := a.GetData().Slot + 1
 		if err := slots.VerifyTime(uint64(s.genesisTime.Unix()), nextSlot, disparity); err != nil {
 			continue
 		}

-		hasState := s.cfg.BeaconDB.HasStateSummary(ctx, bytesutil.ToBytes32(a.Data.BeaconBlockRoot))
-		hasBlock := s.hasBlock(ctx, bytesutil.ToBytes32(a.Data.BeaconBlockRoot))
+		hasState := s.cfg.BeaconDB.HasStateSummary(ctx, bytesutil.ToBytes32(a.GetData().BeaconBlockRoot))
+		hasBlock := s.hasBlock(ctx, bytesutil.ToBytes32(a.GetData().BeaconBlockRoot))
 		if !(hasState && hasBlock) {
 			continue
 		}
@@ -183,17 +185,17 @@ func (s *Service) processAttestations(ctx context.Context, disparity time.Durati
 			log.WithError(err).Error("Could not delete fork choice attestation in pool")
 		}

-		if !helpers.VerifyCheckpointEpoch(a.Data.Target, s.genesisTime) {
+		if !helpers.VerifyCheckpointEpoch(a.GetData().Target, s.genesisTime) {
 			continue
 		}

 		if err := s.receiveAttestationNoPubsub(ctx, a, disparity); err != nil {
 			log.WithFields(logrus.Fields{
-				"slot":             a.Data.Slot,
-				"committeeIndex":   a.Data.CommitteeIndex,
-				"beaconBlockRoot":  fmt.Sprintf("%#x", bytesutil.Trunc(a.Data.BeaconBlockRoot)),
-				"targetRoot":       fmt.Sprintf("%#x", bytesutil.Trunc(a.Data.Target.Root)),
-				"aggregationCount": a.AggregationBits.Count(),
+				"slot":             a.GetData().Slot,
+				"committeeIndex":   a.GetData().CommitteeIndex,
+				"beaconBlockRoot":  fmt.Sprintf("%#x", bytesutil.Trunc(a.GetData().BeaconBlockRoot)),
+				"targetRoot":       fmt.Sprintf("%#x", bytesutil.Trunc(a.GetData().Target.Root)),
+				"aggregationCount": a.GetAggregationBits().Count(),
 			}).WithError(err).Warn("Could not process attestation for fork choice")
 		}
 	}
@@ -204,7 +206,7 @@ func (s *Service) processAttestations(ctx context.Context, disparity time.Durati
 //  1. Validate attestation, update validator's latest vote
 //  2. Apply fork choice to the processed attestation
 //  3. Save latest head info
-func (s *Service) receiveAttestationNoPubsub(ctx context.Context, att *ethpb.Attestation, disparity time.Duration) error {
+func (s *Service) receiveAttestationNoPubsub(ctx context.Context, att ethpb.Att, disparity time.Duration) error {
 	ctx, span := trace.StartSpan(ctx, "beacon-chain.blockchain.receiveAttestationNoPubsub")
 	defer span.End()

--- a/beacon-chain/blockchain/receive_attestation_test.go
+++ b/beacon-chain/blockchain/receive_attestation_test.go
@@ -73,7 +73,7 @@ func TestProcessAttestations_Ok(t *testing.T) {
 	require.NoError(t, service.saveGenesisData(ctx, genesisState))
 	atts, err := util.GenerateAttestations(genesisState, pks, 1, 0, false)
 	require.NoError(t, err)
-	tRoot := bytesutil.ToBytes32(atts[0].Data.Target.Root)
+	tRoot := bytesutil.ToBytes32(atts[0].GetData().Target.Root)
 	copied := genesisState.Copy()
 	copied, err = transition.ProcessSlots(ctx, copied, 1)
 	require.NoError(t, err)
@@ -83,7 +83,11 @@ func TestProcessAttestations_Ok(t *testing.T) {
 	state, blkRoot, err := prepareForkchoiceState(ctx, 0, tRoot, tRoot, params.BeaconConfig().ZeroHash, ojc, ofc)
 	require.NoError(t, err)
 	require.NoError(t, service.cfg.ForkChoiceStore.InsertNode(ctx, state, blkRoot))
-	require.NoError(t, service.cfg.AttPool.SaveForkchoiceAttestations(atts))
+	attsToSave := make([]ethpb.Att, len(atts))
+	for i, a := range atts {
+		attsToSave[i] = a
+	}
+	require.NoError(t, service.cfg.AttPool.SaveForkchoiceAttestations(attsToSave))
 	service.processAttestations(ctx, 0)
 	require.Equal(t, 0, len(service.cfg.AttPool.ForkchoiceAttestations()))
 	require.LogsDoNotContain(t, hook, "Could not process attestation for fork choice")
@@ -121,10 +125,14 @@ func TestService_ProcessAttestationsAndUpdateHead(t *testing.T) {
 	// Generate attestations for this block in Slot 1
 	atts, err := util.GenerateAttestations(copied, pks, 1, 1, false)
 	require.NoError(t, err)
-	require.NoError(t, service.cfg.AttPool.SaveForkchoiceAttestations(atts))
+	attsToSave := make([]ethpb.Att, len(atts))
+	for i, a := range atts {
+		attsToSave[i] = a
+	}
+	require.NoError(t, service.cfg.AttPool.SaveForkchoiceAttestations(attsToSave))
 	// Verify the target is in forkchoice
-	require.Equal(t, true, fcs.HasNode(bytesutil.ToBytes32(atts[0].Data.BeaconBlockRoot)))
-	require.Equal(t, tRoot, bytesutil.ToBytes32(atts[0].Data.BeaconBlockRoot))
+	require.Equal(t, true, fcs.HasNode(bytesutil.ToBytes32(atts[0].GetData().BeaconBlockRoot)))
+	require.Equal(t, tRoot, bytesutil.ToBytes32(atts[0].GetData().BeaconBlockRoot))
 	require.Equal(t, true, fcs.HasNode(service.originBlockRoot))

 	// Insert a new block to forkchoice
--- a/beacon-chain/blockchain/receive_block.go
+++ b/beacon-chain/blockchain/receive_block.go
@@ -13,6 +13,7 @@ import (
 	coreTime "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/das"
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/slasher/types"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	"github.com/prysmaticlabs/prysm/v5/config/features"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/blocks"
@@ -52,7 +53,7 @@ type BlobReceiver interface {

 // SlashingReceiver interface defines the methods of chain service for receiving validated slashing over the wire.
 type SlashingReceiver interface {
-	ReceiveAttesterSlashing(ctx context.Context, slashings *ethpb.AttesterSlashing)
+	ReceiveAttesterSlashing(ctx context.Context, slashing ethpb.AttSlashing)
 }

 // ReceiveBlock is a function that defines the operations (minus pubsub)
@@ -97,6 +98,7 @@ func (s *Service) ReceiveBlock(ctx context.Context, block interfaces.ReadOnlySig
 	eg, _ := errgroup.WithContext(ctx)
 	var postState state.BeaconState
 	eg.Go(func() error {
+		var err error
 		postState, err = s.validateStateTransition(ctx, preState, blockCopy)
 		if err != nil {
 			return errors.Wrap(err, "failed to validate consensus state transition function")
@@ -105,6 +107,7 @@ func (s *Service) ReceiveBlock(ctx context.Context, block interfaces.ReadOnlySig
 	})
 	var isValidPayload bool
 	eg.Go(func() error {
+		var err error
 		isValidPayload, err = s.validateExecutionOnBlock(ctx, preStateVersion, preStateHeader, blockCopy, blockRoot)
 		if err != nil {
 			return errors.Wrap(err, "could not notify the engine of the new payload")
@@ -167,13 +170,8 @@ func (s *Service) ReceiveBlock(ctx context.Context, block interfaces.ReadOnlySig
 	}
 	// Send finalized events and finalized deposits in the background
 	if newFinalized {
-		finalized := s.cfg.ForkChoiceStore.FinalizedCheckpoint()
-		go s.sendNewFinalizedEvent(blockCopy, postState)
-		depCtx, cancel := context.WithTimeout(context.Background(), depositDeadline)
-		go func() {
-			s.insertFinalizedDeposits(depCtx, finalized.Root)
-			cancel()
-		}()
+		// hook to process all post state finalization tasks
+		s.executePostFinalizationTasks(ctx, postState)
 	}

 	// If slasher is configured, forward the attestations in the block via an event feed for processing.
@@ -222,6 +220,19 @@ func (s *Service) ReceiveBlock(ctx context.Context, block interfaces.ReadOnlySig
 	return nil
 }

+func (s *Service) executePostFinalizationTasks(ctx context.Context, finalizedState state.BeaconState) {
+	finalized := s.cfg.ForkChoiceStore.FinalizedCheckpoint()
+	go func() {
+		finalizedState.SaveValidatorIndices() // used to handle Validator index invariant from EIP6110
+		s.sendNewFinalizedEvent(ctx, finalizedState)
+	}()
+	depCtx, cancel := context.WithTimeout(context.Background(), depositDeadline)
+	go func() {
+		s.insertFinalizedDeposits(depCtx, finalized.Root)
+		cancel()
+	}()
+}
+
 // ReceiveBlockBatch processes the whole block batch at once, assuming the block batch is linear ,transitioning
 // the state, performing batch verification of all collected signatures and then performing the appropriate
 // actions for a block post-transition.
@@ -293,10 +304,10 @@ func (s *Service) HasBlock(ctx context.Context, root [32]byte) bool {
 }

 // ReceiveAttesterSlashing receives an attester slashing and inserts it to forkchoice
-func (s *Service) ReceiveAttesterSlashing(ctx context.Context, slashing *ethpb.AttesterSlashing) {
+func (s *Service) ReceiveAttesterSlashing(ctx context.Context, slashing ethpb.AttSlashing) {
 	s.cfg.ForkChoiceStore.Lock()
 	defer s.cfg.ForkChoiceStore.Unlock()
-	s.InsertSlashingsToForkChoiceStore(ctx, []*ethpb.AttesterSlashing{slashing})
+	s.InsertSlashingsToForkChoiceStore(ctx, []ethpb.AttSlashing{slashing})
 }

 // prunePostBlockOperationPools only runs on new head otherwise should return a nil.
@@ -441,7 +452,7 @@ func (s *Service) updateFinalizationOnBlock(ctx context.Context, preState, postS

 // sendNewFinalizedEvent sends a new finalization checkpoint event over the
 // event feed. It needs to be called on the background
-func (s *Service) sendNewFinalizedEvent(signed interfaces.ReadOnlySignedBeaconBlock, postState state.BeaconState) {
+func (s *Service) sendNewFinalizedEvent(ctx context.Context, postState state.BeaconState) {
 	isValidPayload := false
 	s.headLock.RLock()
 	if s.head != nil {
@@ -449,8 +460,17 @@ func (s *Service) sendNewFinalizedEvent(signed interfaces.ReadOnlySignedBeaconBl
 	}
 	s.headLock.RUnlock()

+	blk, err := s.cfg.BeaconDB.Block(ctx, bytesutil.ToBytes32(postState.FinalizedCheckpoint().Root))
+	if err != nil {
+		log.WithError(err).Error("Could not retrieve block for finalized checkpoint root. Finalized event will not be emitted")
+		return
+	}
+	if blk == nil || blk.IsNil() || blk.Block() == nil || blk.Block().IsNil() {
+		log.WithError(err).Error("Block retrieved for finalized checkpoint root is nil. Finalized event will not be emitted")
+		return
+	}
+	stateRoot := blk.Block().StateRoot()
 	// Send an event regarding the new finalized checkpoint over a common event feed.
-	stateRoot := signed.Block().StateRoot()
 	s.cfg.StateNotifier.StateFeed().Send(&feed.Event{
 		Type: statefeed.FinalizedCheckpoint,
 		Data: &ethpbv1.EventFinalizedCheckpoint{
@@ -468,17 +488,17 @@ func (s *Service) sendBlockAttestationsToSlasher(signed interfaces.ReadOnlySigne
 	// is done in the background to avoid adding more load to this critical code path.
 	ctx := context.TODO()
 	for _, att := range signed.Block().Body().Attestations() {
-		committee, err := helpers.BeaconCommitteeFromState(ctx, preState, att.Data.Slot, att.Data.CommitteeIndex)
+		committees, err := helpers.AttestationCommittees(ctx, preState, att)
 		if err != nil {
-			log.WithError(err).Error("Could not get attestation committee")
+			log.WithError(err).Error("Could not get attestation committees")
 			return
 		}
-		indexedAtt, err := attestation.ConvertToIndexed(ctx, att, committee)
+		indexedAtt, err := attestation.ConvertToIndexed(ctx, att, committees...)
 		if err != nil {
 			log.WithError(err).Error("Could not convert to indexed attestation")
 			return
 		}
-		s.cfg.SlasherAttestationsFeed.Send(indexedAtt)
+		s.cfg.SlasherAttestationsFeed.Send(&types.WrappedIndexedAtt{IndexedAtt: indexedAtt})
 	}
 }

@@ -486,7 +506,10 @@ func (s *Service) sendBlockAttestationsToSlasher(signed interfaces.ReadOnlySigne
 func (s *Service) validateExecutionOnBlock(ctx context.Context, ver int, header interfaces.ExecutionData, signed interfaces.ReadOnlySignedBeaconBlock, blockRoot [32]byte) (bool, error) {
 	isValidPayload, err := s.notifyNewPayload(ctx, ver, header, signed)
 	if err != nil {
-		return false, s.handleInvalidExecutionError(ctx, err, blockRoot, signed.Block().ParentRoot())
+		s.cfg.ForkChoiceStore.Lock()
+		err = s.handleInvalidExecutionError(ctx, err, blockRoot, signed.Block().ParentRoot())
+		s.cfg.ForkChoiceStore.Unlock()
+		return false, err
 	}
 	if signed.Version() < version.Capella && isValidPayload {
 		if err := s.validateMergeTransitionBlock(ctx, ver, header, signed); err != nil {
--- a/beacon-chain/blockchain/receive_block_test.go
+++ b/beacon-chain/blockchain/receive_block_test.go
@@ -6,18 +6,24 @@ import (
 	"testing"
 	"time"

+	"github.com/ethereum/go-ethereum/common/hexutil"
 	blockchainTesting "github.com/prysmaticlabs/prysm/v5/beacon-chain/blockchain/testing"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
+	statefeed "github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed/state"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/das"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/operations/voluntaryexits"
+	"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/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"
 	logTest "github.com/sirupsen/logrus/hooks/test"
 )

@@ -378,3 +384,116 @@ func TestHandleBlockBLSToExecutionChanges(t *testing.T) {
 		require.Equal(t, false, pool.ValidatorExists(idx))
 	})
 }
+
+func Test_sendNewFinalizedEvent(t *testing.T) {
+	s, _ := minimalTestService(t)
+	notifier := &blockchainTesting.MockStateNotifier{RecordEvents: true}
+	s.cfg.StateNotifier = notifier
+	finalizedSt, err := util.NewBeaconState()
+	require.NoError(t, err)
+	finalizedStRoot, err := finalizedSt.HashTreeRoot(s.ctx)
+	require.NoError(t, err)
+	b := util.NewBeaconBlock()
+	b.Block.StateRoot = finalizedStRoot[:]
+	sbb, err := blocks.NewSignedBeaconBlock(b)
+	require.NoError(t, err)
+	sbbRoot, err := sbb.Block().HashTreeRoot()
+	require.NoError(t, err)
+	require.NoError(t, s.cfg.BeaconDB.SaveBlock(s.ctx, sbb))
+	st, err := util.NewBeaconState()
+	require.NoError(t, err)
+	require.NoError(t, st.SetFinalizedCheckpoint(&ethpb.Checkpoint{
+		Epoch: 123,
+		Root:  sbbRoot[:],
+	}))
+
+	s.sendNewFinalizedEvent(s.ctx, st)
+
+	require.Equal(t, 1, len(notifier.ReceivedEvents()))
+	e := notifier.ReceivedEvents()[0]
+	assert.Equal(t, statefeed.FinalizedCheckpoint, int(e.Type))
+	fc, ok := e.Data.(*ethpbv1.EventFinalizedCheckpoint)
+	require.Equal(t, true, ok, "event has wrong data type")
+	assert.Equal(t, primitives.Epoch(123), fc.Epoch)
+	assert.DeepEqual(t, sbbRoot[:], fc.Block)
+	assert.DeepEqual(t, finalizedStRoot[:], fc.State)
+	assert.Equal(t, false, fc.ExecutionOptimistic)
+}
+
+func Test_executePostFinalizationTasks(t *testing.T) {
+	resetFn := features.InitWithReset(&features.Flags{
+		EIP6110ValidatorIndexCache: true,
+	})
+	defer resetFn()
+
+	logHook := logTest.NewGlobal()
+
+	headState, err := util.NewBeaconState()
+	require.NoError(t, err)
+	finalizedStRoot, err := headState.HashTreeRoot(context.Background())
+	require.NoError(t, err)
+
+	genesis := util.NewBeaconBlock()
+	genesisRoot, err := genesis.Block.HashTreeRoot()
+	require.NoError(t, err)
+	finalizedSlot := params.BeaconConfig().SlotsPerEpoch*122 + 1
+	headBlock := util.NewBeaconBlock()
+	headBlock.Block.Slot = finalizedSlot
+	headBlock.Block.StateRoot = finalizedStRoot[:]
+	headBlock.Block.ParentRoot = bytesutil.PadTo(genesisRoot[:], 32)
+	headRoot, err := headBlock.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	hexKey := "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"
+	key, err := hexutil.Decode(hexKey)
+	require.NoError(t, err)
+	require.NoError(t, headState.SetValidators([]*ethpb.Validator{
+		{
+			PublicKey:             key,
+			WithdrawalCredentials: make([]byte, fieldparams.RootLength),
+		},
+	}))
+	require.NoError(t, headState.SetSlot(finalizedSlot))
+	require.NoError(t, headState.SetFinalizedCheckpoint(&ethpb.Checkpoint{
+		Epoch: 123,
+		Root:  headRoot[:],
+	}))
+	require.NoError(t, headState.SetGenesisValidatorsRoot(params.BeaconConfig().ZeroHash[:]))
+
+	s, tr := minimalTestService(t, WithFinalizedStateAtStartUp(headState))
+	ctx, beaconDB, stateGen := tr.ctx, tr.db, tr.sg
+
+	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, genesisRoot))
+	util.SaveBlock(t, ctx, beaconDB, genesis)
+	require.NoError(t, beaconDB.SaveState(ctx, headState, headRoot))
+	require.NoError(t, beaconDB.SaveState(ctx, headState, genesisRoot))
+	util.SaveBlock(t, ctx, beaconDB, headBlock)
+	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Epoch: slots.ToEpoch(finalizedSlot), Root: headRoot[:]}))
+
+	require.NoError(t, err)
+	require.NoError(t, stateGen.SaveState(ctx, headRoot, headState))
+	require.NoError(t, beaconDB.SaveLastValidatedCheckpoint(ctx, &ethpb.Checkpoint{Epoch: slots.ToEpoch(finalizedSlot), Root: headRoot[:]}))
+
+	notifier := &blockchainTesting.MockStateNotifier{RecordEvents: true}
+	s.cfg.StateNotifier = notifier
+	s.executePostFinalizationTasks(s.ctx, headState)
+
+	time.Sleep(1 * time.Second) // sleep for a second because event is in a separate go routine
+	require.Equal(t, 1, len(notifier.ReceivedEvents()))
+	e := notifier.ReceivedEvents()[0]
+	assert.Equal(t, statefeed.FinalizedCheckpoint, int(e.Type))
+	fc, ok := e.Data.(*ethpbv1.EventFinalizedCheckpoint)
+	require.Equal(t, true, ok, "event has wrong data type")
+	assert.Equal(t, primitives.Epoch(123), fc.Epoch)
+	assert.DeepEqual(t, headRoot[:], fc.Block)
+	assert.DeepEqual(t, finalizedStRoot[:], fc.State)
+	assert.Equal(t, false, fc.ExecutionOptimistic)
+
+	// check the cache
+	index, ok := headState.ValidatorIndexByPubkey(bytesutil.ToBytes48(key))
+	require.Equal(t, true, ok)
+	require.Equal(t, primitives.ValidatorIndex(0), index) // first index
+
+	// check deposit
+	require.LogsContain(t, logHook, "Finalized deposit insertion completed at index")
+}
--- a/beacon-chain/blockchain/service.go
+++ b/beacon-chain/blockchain/service.go
@@ -11,8 +11,6 @@ import (
 	"time"

 	"github.com/pkg/errors"
-	"go.opencensus.io/trace"
-
 	"github.com/prysmaticlabs/prysm/v5/async/event"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/blockchain/kzg"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
@@ -44,6 +42,7 @@ import (
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	prysmTime "github.com/prysmaticlabs/prysm/v5/time"
 	"github.com/prysmaticlabs/prysm/v5/time/slots"
+	"go.opencensus.io/trace"
 )

 // Service represents a service that handles the internal
@@ -330,6 +329,8 @@ func (s *Service) StartFromSavedState(saved state.BeaconState) error {
 		return errors.Wrap(err, "failed to initialize blockchain service")
 	}

+	saved.SaveValidatorIndices() // used to handle Validator index invariant from EIP6110
+
 	return nil
 }

@@ -504,7 +505,7 @@ func (s *Service) saveGenesisData(ctx context.Context, genesisState state.Beacon
 	}
 	genesisBlk, err := s.cfg.BeaconDB.GenesisBlock(ctx)
 	if err != nil || genesisBlk == nil || genesisBlk.IsNil() {
-		return fmt.Errorf("could not load genesis block: %v", err)
+		return fmt.Errorf("could not load genesis block: %w", err)
 	}
 	genesisBlkRoot, err := genesisBlk.Block().HashTreeRoot()
 	if err != nil {
--- a/beacon-chain/blockchain/service_test.go
+++ b/beacon-chain/blockchain/service_test.go
@@ -8,9 +8,10 @@ import (
 	"time"

 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache/depositcache"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/core/blocks"
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache/depositsnapshot"
+	"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/transition"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/db"
@@ -29,6 +30,7 @@ import (
 	"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/container/trie"
 	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
@@ -80,7 +82,7 @@ func setupBeaconChain(t *testing.T, beaconDB db.Database) *Service {
 	attService, err := attestations.NewService(ctx, &attestations.Config{Pool: attestations.NewPool()})
 	require.NoError(t, err)

-	depositCache, err := depositcache.New()
+	depositCache, err := depositsnapshot.New()
 	require.NoError(t, err)

 	fc := doublylinkedtree.New()
@@ -203,7 +205,7 @@ func TestChainService_InitializeBeaconChain(t *testing.T) {
 		BlockHash:    make([]byte, 32),
 	})
 	require.NoError(t, err)
-	genState, err = blocks.ProcessPreGenesisDeposits(ctx, genState, deposits)
+	genState, err = altair.ProcessPreGenesisDeposits(ctx, genState, deposits)
 	require.NoError(t, err)

 	_, err = bc.initializeBeaconChain(ctx, time.Unix(0, 0), genState, &ethpb.Eth1Data{DepositRoot: hashTreeRoot[:], BlockHash: make([]byte, 32)})
@@ -499,6 +501,66 @@ func TestChainService_EverythingOptimistic(t *testing.T) {
 	require.Equal(t, true, op)
 }

+func TestStartFromSavedState_ValidatorIndexCacheUpdated(t *testing.T) {
+	resetFn := features.InitWithReset(&features.Flags{
+		EnableStartOptimistic:      true,
+		EIP6110ValidatorIndexCache: true,
+	})
+	defer resetFn()
+
+	genesis := util.NewBeaconBlock()
+	genesisRoot, err := genesis.Block.HashTreeRoot()
+	require.NoError(t, err)
+	finalizedSlot := params.BeaconConfig().SlotsPerEpoch*2 + 1
+	headBlock := util.NewBeaconBlock()
+	headBlock.Block.Slot = finalizedSlot
+	headBlock.Block.ParentRoot = bytesutil.PadTo(genesisRoot[:], 32)
+	headState, err := util.NewBeaconState()
+	require.NoError(t, err)
+	hexKey := "0x93247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"
+	key, err := hexutil.Decode(hexKey)
+	require.NoError(t, err)
+	hexKey2 := "0x42247f2209abcacf57b75a51dafae777f9dd38bc7053d1af526f220a7489a6d3a2753e5f3e8b1cfe39b56f43611df74a"
+	key2, err := hexutil.Decode(hexKey2)
+	require.NoError(t, err)
+	require.NoError(t, headState.SetValidators([]*ethpb.Validator{
+		{
+			PublicKey:             key,
+			WithdrawalCredentials: make([]byte, fieldparams.RootLength),
+		},
+		{
+			PublicKey:             key2,
+			WithdrawalCredentials: make([]byte, fieldparams.RootLength),
+		},
+	}))
+	require.NoError(t, headState.SetSlot(finalizedSlot))
+	require.NoError(t, headState.SetGenesisValidatorsRoot(params.BeaconConfig().ZeroHash[:]))
+	headRoot, err := headBlock.Block.HashTreeRoot()
+	require.NoError(t, err)
+
+	c, tr := minimalTestService(t, WithFinalizedStateAtStartUp(headState))
+	ctx, beaconDB, stateGen := tr.ctx, tr.db, tr.sg
+
+	require.NoError(t, beaconDB.SaveGenesisBlockRoot(ctx, genesisRoot))
+	util.SaveBlock(t, ctx, beaconDB, genesis)
+	require.NoError(t, beaconDB.SaveState(ctx, headState, headRoot))
+	require.NoError(t, beaconDB.SaveState(ctx, headState, genesisRoot))
+	util.SaveBlock(t, ctx, beaconDB, headBlock)
+	require.NoError(t, beaconDB.SaveFinalizedCheckpoint(ctx, &ethpb.Checkpoint{Epoch: slots.ToEpoch(finalizedSlot), Root: headRoot[:]}))
+
+	require.NoError(t, err)
+	require.NoError(t, stateGen.SaveState(ctx, headRoot, headState))
+	require.NoError(t, beaconDB.SaveLastValidatedCheckpoint(ctx, &ethpb.Checkpoint{Epoch: slots.ToEpoch(finalizedSlot), Root: headRoot[:]}))
+	require.NoError(t, c.StartFromSavedState(headState))
+
+	index, ok := headState.ValidatorIndexByPubkey(bytesutil.ToBytes48(key))
+	require.Equal(t, true, ok)
+	require.Equal(t, primitives.ValidatorIndex(0), index) // first index
+	index2, ok := headState.ValidatorIndexByPubkey(bytesutil.ToBytes48(key2))
+	require.Equal(t, true, ok)
+	require.Equal(t, primitives.ValidatorIndex(1), index2) // first index
+}
+
 // MockClockSetter satisfies the ClockSetter interface for testing the conditions where blockchain.Service should
 // call SetGenesis.
 type MockClockSetter struct {
--- a/beacon-chain/blockchain/setup_test.go
+++ b/beacon-chain/blockchain/setup_test.go
@@ -8,11 +8,12 @@ import (
 	"github.com/prysmaticlabs/prysm/v5/async/event"
 	mock "github.com/prysmaticlabs/prysm/v5/beacon-chain/blockchain/testing"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache/depositcache"
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache/depositsnapshot"
 	statefeed "github.com/prysmaticlabs/prysm/v5/beacon-chain/core/feed/state"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/db"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/db/filesystem"
 	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/beacon-chain/forkchoice"
 	doublylinkedtree "github.com/prysmaticlabs/prysm/v5/beacon-chain/forkchoice/doubly-linked-tree"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/operations/attestations"
@@ -49,7 +50,7 @@ func (mb *mockBroadcaster) Broadcast(_ context.Context, _ proto.Message) error {
 	return nil
 }

-func (mb *mockBroadcaster) BroadcastAttestation(_ context.Context, _ uint64, _ *ethpb.Attestation) error {
+func (mb *mockBroadcaster) BroadcastAttestation(_ context.Context, _ uint64, _ ethpb.Att) error {
 	mb.broadcastCalled = true
 	return nil
 }
@@ -79,7 +80,7 @@ type testServiceRequirements struct {
 	attPool attestations.Pool
 	attSrv  *attestations.Service
 	blsPool *blstoexec.Pool
-	dc      *depositcache.DepositCache
+	dc      *depositsnapshot.Cache
 }

 func minimalTestService(t *testing.T, opts ...Option) (*Service, *testServiceRequirements) {
@@ -94,7 +95,7 @@ func minimalTestService(t *testing.T, opts ...Option) (*Service, *testServiceReq
 	attSrv, err := attestations.NewService(ctx, &attestations.Config{Pool: attPool})
 	require.NoError(t, err)
 	blsPool := blstoexec.NewPool()
-	dc, err := depositcache.New()
+	dc, err := depositsnapshot.New()
 	require.NoError(t, err)
 	req := &testServiceRequirements{
 		ctx:     ctx,
@@ -120,6 +121,7 @@ func minimalTestService(t *testing.T, opts ...Option) (*Service, *testServiceReq
 		WithTrackedValidatorsCache(cache.NewTrackedValidatorsCache()),
 		WithBlobStorage(filesystem.NewEphemeralBlobStorage(t)),
 		WithSyncChecker(mock.MockChecker{}),
+		WithExecutionEngineCaller(&mockExecution.EngineClient{}),
 	}
 	// append the variadic opts so they override the defaults by being processed afterwards
 	opts = append(defOpts, opts...)
--- a/beacon-chain/blockchain/testing/mock.go
+++ b/beacon-chain/blockchain/testing/mock.go
@@ -414,8 +414,8 @@ func (*ChainService) HeadGenesisValidatorsRoot() [32]byte {
 }

 // VerifyLmdFfgConsistency mocks VerifyLmdFfgConsistency and always returns nil.
-func (*ChainService) VerifyLmdFfgConsistency(_ context.Context, a *ethpb.Attestation) error {
-	if !bytes.Equal(a.Data.BeaconBlockRoot, a.Data.Target.Root) {
+func (*ChainService) VerifyLmdFfgConsistency(_ context.Context, a ethpb.Att) error {
+	if !bytes.Equal(a.GetData().BeaconBlockRoot, a.GetData().Target.Root) {
 		return errors.New("LMD and FFG miss matched")
 	}
 	return nil
@@ -495,7 +495,7 @@ func (s *ChainService) UpdateHead(ctx context.Context, slot primitives.Slot) {
 }

 // ReceiveAttesterSlashing mocks the same method in the chain service.
-func (*ChainService) ReceiveAttesterSlashing(context.Context, *ethpb.AttesterSlashing) {}
+func (*ChainService) ReceiveAttesterSlashing(context.Context, ethpb.AttSlashing) {}

 // IsFinalized mocks the same method in the chain service.
 func (s *ChainService) IsFinalized(_ context.Context, blockRoot [32]byte) bool {
--- a/beacon-chain/builder/testing/mock.go
+++ b/beacon-chain/builder/testing/mock.go
@@ -2,7 +2,6 @@ package testing

 import (
 	"context"
-	"math/big"

 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/api/client/builder"
@@ -55,13 +54,13 @@ func (s *MockBuilderService) SubmitBlindedBlock(_ context.Context, b interfaces.
 		}
 		return w, nil, s.ErrSubmitBlindedBlock
 	case version.Capella:
-		w, err := blocks.WrappedExecutionPayloadCapella(s.PayloadCapella, big.NewInt(0))
+		w, err := blocks.WrappedExecutionPayloadCapella(s.PayloadCapella)
 		if err != nil {
 			return nil, nil, errors.Wrap(err, "could not wrap capella payload")
 		}
 		return w, nil, s.ErrSubmitBlindedBlock
 	case version.Deneb:
-		w, err := blocks.WrappedExecutionPayloadDeneb(s.PayloadDeneb, big.NewInt(0))
+		w, err := blocks.WrappedExecutionPayloadDeneb(s.PayloadDeneb)
 		if err != nil {
 			return nil, nil, errors.Wrap(err, "could not wrap deneb payload")
 		}
--- a/beacon-chain/cache/BUILD.bazel
+++ b/beacon-chain/cache/BUILD.bazel
@@ -6,6 +6,7 @@ go_library(
        "active_balance.go",
        "active_balance_disabled.go",  # keep
        "attestation_data.go",
+        "balance_cache_key.go",
        "checkpoint_state.go",
        "committee.go",
        "committee_disabled.go",  # keep
@@ -70,6 +71,7 @@ go_test(
        "committee_fuzz_test.go",
        "committee_test.go",
        "payload_id_test.go",
+        "private_access_test.go",
        "proposer_indices_test.go",
        "registration_test.go",
        "skip_slot_cache_test.go",
@@ -93,6 +95,7 @@ go_test(
        "//testing/util:go_default_library",
        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
        "@com_github_google_gofuzz//:go_default_library",
+        "@com_github_hashicorp_golang_lru//:go_default_library",
        "@com_github_stretchr_testify//require:go_default_library",
        "@org_golang_google_protobuf//proto:go_default_library",
    ],
--- a/beacon-chain/cache/active_balance.go
+++ b/beacon-chain/cache/active_balance.go
@@ -3,17 +3,13 @@
 package cache

 import (
-	"encoding/binary"
 	"sync"

 	lru "github.com/hashicorp/golang-lru"
-	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promauto"
 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
 	lruwrpr "github.com/prysmaticlabs/prysm/v5/cache/lru"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 )

 const (
@@ -86,36 +82,3 @@ func (c *BalanceCache) Get(st state.ReadOnlyBeaconState) (uint64, error) {
 	balanceCacheHit.Inc()
 	return value.(uint64), nil
 }
-
-// Given input state `st`, balance key is constructed as:
-// (block_root in `st` at epoch_start_slot - 1) + current_epoch + validator_count
-func balanceCacheKey(st state.ReadOnlyBeaconState) (string, error) {
-	slotsPerEpoch := params.BeaconConfig().SlotsPerEpoch
-	currentEpoch := st.Slot().DivSlot(slotsPerEpoch)
-	epochStartSlot, err := slotsPerEpoch.SafeMul(uint64(currentEpoch))
-	if err != nil {
-		// impossible condition due to early division
-		return "", errors.Errorf("start slot calculation overflows: %v", err)
-	}
-	prevSlot := primitives.Slot(0)
-	if epochStartSlot > 1 {
-		prevSlot = epochStartSlot - 1
-	}
-	r, err := st.BlockRootAtIndex(uint64(prevSlot % params.BeaconConfig().SlotsPerHistoricalRoot))
-	if err != nil {
-		// impossible condition because index is always constrained within state
-		return "", err
-	}
-
-	// Mix in current epoch
-	b := make([]byte, 8)
-	binary.LittleEndian.PutUint64(b, uint64(currentEpoch))
-	key := append(r, b...)
-
-	// Mix in validator count
-	b = make([]byte, 8)
-	binary.LittleEndian.PutUint64(b, uint64(st.NumValidators()))
-	key = append(key, b...)
-
-	return string(key), nil
-}
--- a/beacon-chain/cache/active_balance_test.go
+++ b/beacon-chain/cache/active_balance_test.go
@@ -1,12 +1,13 @@
 //go:build !fuzz

-package cache
+package cache_test

 import (
 	"encoding/binary"
 	"math"
 	"testing"

+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
 	state_native "github.com/prysmaticlabs/prysm/v5/beacon-chain/state/state-native"
 	"github.com/prysmaticlabs/prysm/v5/config/params"
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
@@ -27,33 +28,33 @@ func TestBalanceCache_AddGetBalance(t *testing.T) {
 	st, err := state_native.InitializeFromProtoPhase0(raw)
 	require.NoError(t, err)

-	cache := NewEffectiveBalanceCache()
-	_, err = cache.Get(st)
-	require.ErrorContains(t, ErrNotFound.Error(), err)
+	cc := cache.NewEffectiveBalanceCache()
+	_, err = cc.Get(st)
+	require.ErrorContains(t, cache.ErrNotFound.Error(), err)

 	b := uint64(100)
-	require.NoError(t, cache.AddTotalEffectiveBalance(st, b))
-	cachedB, err := cache.Get(st)
+	require.NoError(t, cc.AddTotalEffectiveBalance(st, b))
+	cachedB, err := cc.Get(st)
 	require.NoError(t, err)
 	require.Equal(t, b, cachedB)

 	require.NoError(t, st.SetSlot(1000))
-	_, err = cache.Get(st)
-	require.ErrorContains(t, ErrNotFound.Error(), err)
+	_, err = cc.Get(st)
+	require.ErrorContains(t, cache.ErrNotFound.Error(), err)

 	b = uint64(200)
-	require.NoError(t, cache.AddTotalEffectiveBalance(st, b))
-	cachedB, err = cache.Get(st)
+	require.NoError(t, cc.AddTotalEffectiveBalance(st, b))
+	cachedB, err = cc.Get(st)
 	require.NoError(t, err)
 	require.Equal(t, b, cachedB)

 	require.NoError(t, st.SetSlot(1000+params.BeaconConfig().SlotsPerHistoricalRoot))
-	_, err = cache.Get(st)
-	require.ErrorContains(t, ErrNotFound.Error(), err)
+	_, err = cc.Get(st)
+	require.ErrorContains(t, cache.ErrNotFound.Error(), err)

 	b = uint64(300)
-	require.NoError(t, cache.AddTotalEffectiveBalance(st, b))
-	cachedB, err = cache.Get(st)
+	require.NoError(t, cc.AddTotalEffectiveBalance(st, b))
+	cachedB, err = cc.Get(st)
 	require.NoError(t, err)
 	require.Equal(t, b, cachedB)
 }
@@ -72,6 +73,6 @@ func TestBalanceCache_BalanceKey(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, st.SetSlot(primitives.Slot(math.MaxUint64)))

-	_, err = balanceCacheKey(st)
+	_, err = cache.BalanceCacheKey(st)
 	require.NoError(t, err)
 }
--- a/beacon-chain/cache/balance_cache_key.go
+++ b/beacon-chain/cache/balance_cache_key.go
@@ -0,0 +1,43 @@
+package cache
+
+import (
+	"encoding/binary"
+	"fmt"
+
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
+	"github.com/prysmaticlabs/prysm/v5/config/params"
+	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
+)
+
+// Given input state `st`, balance key is constructed as:
+// (block_root in `st` at epoch_start_slot - 1) + current_epoch + validator_count
+func balanceCacheKey(st state.ReadOnlyBeaconState) (string, error) {
+	slotsPerEpoch := params.BeaconConfig().SlotsPerEpoch
+	currentEpoch := st.Slot().DivSlot(slotsPerEpoch)
+	epochStartSlot, err := slotsPerEpoch.SafeMul(uint64(currentEpoch))
+	if err != nil {
+		// impossible condition due to early division
+		return "", fmt.Errorf("start slot calculation overflows: %w", err)
+	}
+	prevSlot := primitives.Slot(0)
+	if epochStartSlot > 1 {
+		prevSlot = epochStartSlot - 1
+	}
+	r, err := st.BlockRootAtIndex(uint64(prevSlot % params.BeaconConfig().SlotsPerHistoricalRoot))
+	if err != nil {
+		// impossible condition because index is always constrained within state
+		return "", err
+	}
+
+	// Mix in current epoch
+	b := make([]byte, 8)
+	binary.LittleEndian.PutUint64(b, uint64(currentEpoch))
+	key := append(r, b...)
+
+	// Mix in validator count
+	b = make([]byte, 8)
+	binary.LittleEndian.PutUint64(b, uint64(st.NumValidators()))
+	key = append(key, b...)
+
+	return string(key), nil
+}
--- a/beacon-chain/cache/checkpoint_state_test.go
+++ b/beacon-chain/cache/checkpoint_state_test.go
@@ -1,8 +1,9 @@
-package cache
+package cache_test

 import (
 	"testing"

+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
 	"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/params"
@@ -15,7 +16,7 @@ import (
 )

 func TestCheckpointStateCache_StateByCheckpoint(t *testing.T) {
-	cache := NewCheckpointStateCache()
+	cache := cache.NewCheckpointStateCache()

 	cp1 := &ethpb.Checkpoint{Epoch: 1, Root: bytesutil.PadTo([]byte{'A'}, 32)}
 	st, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
@@ -58,16 +59,16 @@ func TestCheckpointStateCache_StateByCheckpoint(t *testing.T) {
 }

 func TestCheckpointStateCache_MaxSize(t *testing.T) {
-	c := NewCheckpointStateCache()
+	c := cache.NewCheckpointStateCache()
 	st, err := state_native.InitializeFromProtoPhase0(&ethpb.BeaconState{
 		Slot: 0,
 	})
 	require.NoError(t, err)

-	for i := uint64(0); i < uint64(maxCheckpointStateSize+100); i++ {
+	for i := uint64(0); i < uint64(cache.MaxCheckpointStateSize()+100); i++ {
 		require.NoError(t, st.SetSlot(primitives.Slot(i)))
 		require.NoError(t, c.AddCheckpointState(&ethpb.Checkpoint{Epoch: primitives.Epoch(i), Root: make([]byte, 32)}, st))
 	}

-	assert.Equal(t, maxCheckpointStateSize, len(c.cache.Keys()))
+	assert.Equal(t, cache.MaxCheckpointStateSize(), len(c.Cache().Keys()))
 }
--- a/beacon-chain/cache/depositcache/BUILD.bazel
+++ b/beacon-chain/cache/depositcache/BUILD.bazel
@@ -1,50 +0,0 @@
-load("@prysm//tools/go:def.bzl", "go_library", "go_test")
-
-go_library(
-    name = "go_default_library",
-    srcs = [
-        "deposits_cache.go",
-        "log.go",
-        "pending_deposits.go",
-    ],
-    importpath = "github.com/prysmaticlabs/prysm/v5/beacon-chain/cache/depositcache",
-    visibility = [
-        "//beacon-chain:__subpackages__",
-        "//testing/spectest:__subpackages__",
-    ],
-    deps = [
-        "//beacon-chain/cache:go_default_library",
-        "//config/fieldparams:go_default_library",
-        "//config/params:go_default_library",
-        "//container/trie:go_default_library",
-        "//crypto/hash:go_default_library",
-        "//encoding/bytesutil:go_default_library",
-        "//proto/prysm/v1alpha1:go_default_library",
-        "@com_github_ethereum_go_ethereum//common:go_default_library",
-        "@com_github_pkg_errors//:go_default_library",
-        "@com_github_prometheus_client_golang//prometheus:go_default_library",
-        "@com_github_prometheus_client_golang//prometheus/promauto:go_default_library",
-        "@com_github_sirupsen_logrus//:go_default_library",
-        "@io_opencensus_go//trace:go_default_library",
-    ],
-)
-
-go_test(
-    name = "go_default_test",
-    srcs = [
-        "deposits_cache_test.go",
-        "pending_deposits_test.go",
-    ],
-    embed = [":go_default_library"],
-    deps = [
-        "//beacon-chain/cache:go_default_library",
-        "//config/params:go_default_library",
-        "//container/trie:go_default_library",
-        "//encoding/bytesutil:go_default_library",
-        "//proto/prysm/v1alpha1:go_default_library",
-        "//testing/assert:go_default_library",
-        "//testing/require:go_default_library",
-        "@com_github_sirupsen_logrus//hooks/test:go_default_library",
-        "@org_golang_google_protobuf//proto:go_default_library",
-    ],
-)
--- a/beacon-chain/cache/depositcache/deposits_cache.go
+++ b/beacon-chain/cache/depositcache/deposits_cache.go
@@ -1,327 +0,0 @@
-// Package depositcache is the source of validator deposits maintained
-// in-memory by the beacon node – deposits processed from the
-// eth1 powchain are then stored in this cache to be accessed by
-// any other service during a beacon node's runtime.
-package depositcache
-
-import (
-	"context"
-	"encoding/hex"
-	"math/big"
-	"sort"
-	"sync"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/pkg/errors"
-	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/client_golang/prometheus/promauto"
-	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
-	fieldparams "github.com/prysmaticlabs/prysm/v5/config/fieldparams"
-	"github.com/prysmaticlabs/prysm/v5/config/params"
-	"github.com/prysmaticlabs/prysm/v5/container/trie"
-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/sirupsen/logrus"
-	"go.opencensus.io/trace"
-)
-
-var (
-	historicalDepositsCount = promauto.NewCounter(prometheus.CounterOpts{
-		Name: "beacondb_all_deposits",
-		Help: "The number of total deposits in the beaconDB in-memory database",
-	})
-)
-
-// FinalizedDeposits stores the trie of deposits that have been included
-// in the beacon state up to the latest finalized checkpoint.
-type FinalizedDeposits struct {
-	deposits        *trie.SparseMerkleTrie
-	merkleTrieIndex int64
-}
-
-// DepositCache stores all in-memory deposit objects. This
-// stores all the deposit related data that is required by the beacon-node.
-type DepositCache struct {
-	// Beacon chain deposits in memory.
-	pendingDeposits   []*ethpb.DepositContainer
-	deposits          []*ethpb.DepositContainer
-	finalizedDeposits FinalizedDeposits
-	depositsByKey     map[[fieldparams.BLSPubkeyLength]byte][]*ethpb.DepositContainer
-	depositsLock      sync.RWMutex
-}
-
-// New instantiates a new deposit cache
-func New() (*DepositCache, error) {
-	finalizedDepositsTrie, err := trie.NewTrie(params.BeaconConfig().DepositContractTreeDepth)
-	if err != nil {
-		return nil, err
-	}
-
-	// finalizedDeposits.merkleTrieIndex is initialized to -1 because it represents the index of the last trie item.
-	// Inserting the first item into the trie will set the value of the index to 0.
-	return &DepositCache{
-		pendingDeposits:   []*ethpb.DepositContainer{},
-		deposits:          []*ethpb.DepositContainer{},
-		depositsByKey:     map[[fieldparams.BLSPubkeyLength]byte][]*ethpb.DepositContainer{},
-		finalizedDeposits: FinalizedDeposits{deposits: finalizedDepositsTrie, merkleTrieIndex: -1},
-	}, nil
-}
-
-// InsertDeposit into the database. If deposit or block number are nil
-// then this method does nothing.
-func (dc *DepositCache) InsertDeposit(ctx context.Context, d *ethpb.Deposit, blockNum uint64, index int64, depositRoot [32]byte) error {
-	_, span := trace.StartSpan(ctx, "DepositsCache.InsertDeposit")
-	defer span.End()
-	if d == nil {
-		log.WithFields(logrus.Fields{
-			"block":       blockNum,
-			"deposit":     d,
-			"index":       index,
-			"depositRoot": hex.EncodeToString(depositRoot[:]),
-		}).Warn("Ignoring nil deposit insertion")
-		return errors.New("nil deposit inserted into the cache")
-	}
-	dc.depositsLock.Lock()
-	defer dc.depositsLock.Unlock()
-
-	if int(index) != len(dc.deposits) {
-		return errors.Errorf("wanted deposit with index %d to be inserted but received %d", len(dc.deposits), index)
-	}
-	// Keep the slice sorted on insertion in order to avoid costly sorting on retrieval.
-	heightIdx := sort.Search(len(dc.deposits), func(i int) bool { return dc.deposits[i].Index >= index })
-	depCtr := &ethpb.DepositContainer{Deposit: d, Eth1BlockHeight: blockNum, DepositRoot: depositRoot[:], Index: index}
-	newDeposits := append(
-		[]*ethpb.DepositContainer{depCtr},
-		dc.deposits[heightIdx:]...)
-	dc.deposits = append(dc.deposits[:heightIdx], newDeposits...)
-	// Append the deposit to our map, in the event no deposits
-	// exist for the pubkey , it is simply added to the map.
-	pubkey := bytesutil.ToBytes48(d.Data.PublicKey)
-	dc.depositsByKey[pubkey] = append(dc.depositsByKey[pubkey], depCtr)
-	historicalDepositsCount.Inc()
-	return nil
-}
-
-// InsertDepositContainers inserts a set of deposit containers into our deposit cache.
-func (dc *DepositCache) InsertDepositContainers(ctx context.Context, ctrs []*ethpb.DepositContainer) {
-	_, span := trace.StartSpan(ctx, "DepositsCache.InsertDepositContainers")
-	defer span.End()
-	dc.depositsLock.Lock()
-	defer dc.depositsLock.Unlock()
-
-	sort.SliceStable(ctrs, func(i int, j int) bool { return ctrs[i].Index < ctrs[j].Index })
-	dc.deposits = ctrs
-	for _, c := range ctrs {
-		// Use a new value, as the reference
-		// of c changes in the next iteration.
-		newPtr := c
-		pKey := bytesutil.ToBytes48(newPtr.Deposit.Data.PublicKey)
-		dc.depositsByKey[pKey] = append(dc.depositsByKey[pKey], newPtr)
-	}
-	historicalDepositsCount.Add(float64(len(ctrs)))
-}
-
-// InsertFinalizedDeposits inserts deposits up to eth1DepositIndex (inclusive) into the finalized deposits cache.
-func (dc *DepositCache) InsertFinalizedDeposits(ctx context.Context,
-	eth1DepositIndex int64, _ common.Hash, _ uint64) error {
-	_, span := trace.StartSpan(ctx, "DepositsCache.InsertFinalizedDeposits")
-	defer span.End()
-	dc.depositsLock.Lock()
-	defer dc.depositsLock.Unlock()
-
-	depositTrie := dc.finalizedDeposits.Deposits()
-	insertIndex := int(dc.finalizedDeposits.merkleTrieIndex + 1)
-
-	// Don't insert into finalized trie if there is no deposit to
-	// insert.
-	if len(dc.deposits) == 0 {
-		return nil
-	}
-	// In the event we have less deposits than we need to
-	// finalize we finalize till the index on which we do have it.
-	if len(dc.deposits) <= int(eth1DepositIndex) {
-		eth1DepositIndex = int64(len(dc.deposits)) - 1
-	}
-	// If we finalize to some lower deposit index, we
-	// ignore it.
-	if int(eth1DepositIndex) < insertIndex {
-		return nil
-	}
-	for _, d := range dc.deposits {
-		if d.Index <= dc.finalizedDeposits.merkleTrieIndex {
-			continue
-		}
-		if d.Index > eth1DepositIndex {
-			break
-		}
-		depHash, err := d.Deposit.Data.HashTreeRoot()
-		if err != nil {
-			return errors.Wrap(err, "could not hash deposit data")
-		}
-		if err = depositTrie.Insert(depHash[:], insertIndex); err != nil {
-			return errors.Wrap(err, "could not insert deposit hash")
-		}
-		insertIndex++
-	}
-	tree, ok := depositTrie.(*trie.SparseMerkleTrie)
-	if !ok {
-		return errors.New("not a sparse merkle tree")
-	}
-	dc.finalizedDeposits = FinalizedDeposits{
-		deposits:        tree,
-		merkleTrieIndex: eth1DepositIndex,
-	}
-	return nil
-}
-
-// AllDepositContainers returns all historical deposit containers.
-func (dc *DepositCache) AllDepositContainers(ctx context.Context) []*ethpb.DepositContainer {
-	_, span := trace.StartSpan(ctx, "DepositsCache.AllDepositContainers")
-	defer span.End()
-	dc.depositsLock.RLock()
-	defer dc.depositsLock.RUnlock()
-
-	// Make a shallow copy of the deposits and return that. This way, the
-	// caller can safely iterate over the returned list of deposits without
-	// the possibility of new deposits showing up. If we were to return the
-	// list without a copy, when a new deposit is added to the cache, it
-	// would also be present in the returned value. This could result in a
-	// race condition if the list is being iterated over.
-	//
-	// It's not necessary to make a deep copy of this list because the
-	// deposits in the cache should never be modified. It is still possible
-	// for the caller to modify one of the underlying deposits and modify
-	// the cache, but that's not a race condition. Also, a deep copy would
-	// take too long and use too much memory.
-	deposits := make([]*ethpb.DepositContainer, len(dc.deposits))
-	copy(deposits, dc.deposits)
-	return deposits
-}
-
-// AllDeposits returns a list of historical deposits until the given block number
-// (inclusive). If no block is specified then this method returns all historical deposits.
-func (dc *DepositCache) AllDeposits(ctx context.Context, untilBlk *big.Int) []*ethpb.Deposit {
-	dc.depositsLock.RLock()
-	defer dc.depositsLock.RUnlock()
-
-	return dc.allDeposits(untilBlk)
-}
-
-func (dc *DepositCache) allDeposits(untilBlk *big.Int) []*ethpb.Deposit {
-	var deposits []*ethpb.Deposit
-	for _, ctnr := range dc.deposits {
-		if untilBlk == nil || untilBlk.Uint64() >= ctnr.Eth1BlockHeight {
-			deposits = append(deposits, ctnr.Deposit)
-		}
-	}
-	return deposits
-}
-
-// DepositsNumberAndRootAtHeight returns number of deposits made up to blockheight and the
-// root that corresponds to the latest deposit at that blockheight.
-func (dc *DepositCache) DepositsNumberAndRootAtHeight(ctx context.Context, blockHeight *big.Int) (uint64, [32]byte) {
-	_, span := trace.StartSpan(ctx, "DepositsCache.DepositsNumberAndRootAtHeight")
-	defer span.End()
-	dc.depositsLock.RLock()
-	defer dc.depositsLock.RUnlock()
-	heightIdx := sort.Search(len(dc.deposits), func(i int) bool { return dc.deposits[i].Eth1BlockHeight > blockHeight.Uint64() })
-	// send the deposit root of the empty trie, if eth1follow distance is greater than the time of the earliest
-	// deposit.
-	if heightIdx == 0 {
-		return 0, [32]byte{}
-	}
-	return uint64(heightIdx), bytesutil.ToBytes32(dc.deposits[heightIdx-1].DepositRoot)
-}
-
-// DepositByPubkey looks through historical deposits and finds one which contains
-// a certain public key within its deposit data.
-func (dc *DepositCache) DepositByPubkey(ctx context.Context, pubKey []byte) (*ethpb.Deposit, *big.Int) {
-	_, span := trace.StartSpan(ctx, "DepositsCache.DepositByPubkey")
-	defer span.End()
-	dc.depositsLock.RLock()
-	defer dc.depositsLock.RUnlock()
-
-	var deposit *ethpb.Deposit
-	var blockNum *big.Int
-	deps, ok := dc.depositsByKey[bytesutil.ToBytes48(pubKey)]
-	if !ok || len(deps) == 0 {
-		return deposit, blockNum
-	}
-	// We always return the first deposit if a particular
-	// validator key has multiple deposits assigned to
-	// it.
-	deposit = deps[0].Deposit
-	blockNum = big.NewInt(int64(deps[0].Eth1BlockHeight))
-	return deposit, blockNum
-}
-
-// FinalizedDeposits returns the finalized deposits trie.
-func (dc *DepositCache) FinalizedDeposits(ctx context.Context) (cache.FinalizedDeposits, error) {
-	_, span := trace.StartSpan(ctx, "DepositsCache.FinalizedDeposits")
-	defer span.End()
-	dc.depositsLock.RLock()
-	defer dc.depositsLock.RUnlock()
-
-	return &FinalizedDeposits{
-		deposits:        dc.finalizedDeposits.deposits.Copy(),
-		merkleTrieIndex: dc.finalizedDeposits.merkleTrieIndex,
-	}, nil
-}
-
-// NonFinalizedDeposits returns the list of non-finalized deposits until the given block number (inclusive).
-// If no block is specified then this method returns all non-finalized deposits.
-func (dc *DepositCache) NonFinalizedDeposits(ctx context.Context, lastFinalizedIndex int64, untilBlk *big.Int) []*ethpb.Deposit {
-	_, span := trace.StartSpan(ctx, "DepositsCache.NonFinalizedDeposits")
-	defer span.End()
-	dc.depositsLock.RLock()
-	defer dc.depositsLock.RUnlock()
-
-	if dc.finalizedDeposits.Deposits() == nil {
-		return dc.allDeposits(untilBlk)
-	}
-
-	var deposits []*ethpb.Deposit
-	for _, d := range dc.deposits {
-		if (d.Index > lastFinalizedIndex) && (untilBlk == nil || untilBlk.Uint64() >= d.Eth1BlockHeight) {
-			deposits = append(deposits, d.Deposit)
-		}
-	}
-
-	return deposits
-}
-
-// PruneProofs removes proofs from all deposits whose index is equal or less than untilDepositIndex.
-func (dc *DepositCache) PruneProofs(ctx context.Context, untilDepositIndex int64) error {
-	_, span := trace.StartSpan(ctx, "DepositsCache.PruneProofs")
-	defer span.End()
-	dc.depositsLock.Lock()
-	defer dc.depositsLock.Unlock()
-
-	if untilDepositIndex >= int64(len(dc.deposits)) {
-		untilDepositIndex = int64(len(dc.deposits) - 1)
-	}
-
-	for i := untilDepositIndex; i >= 0; i-- {
-		// Finding a nil proof means that all proofs up to this deposit have been already pruned.
-		if dc.deposits[i].Deposit.Proof == nil {
-			break
-		}
-		dc.deposits[i].Deposit.Proof = nil
-	}
-
-	return nil
-}
-
-// Deposits returns the cached internal deposit tree.
-func (fd *FinalizedDeposits) Deposits() cache.MerkleTree {
-	if fd.deposits != nil {
-		return fd.deposits
-	}
-	return nil
-}
-
-// MerkleTrieIndex represents the last finalized index in
-// the finalized deposit container.
-func (fd *FinalizedDeposits) MerkleTrieIndex() int64 {
-	return fd.merkleTrieIndex
-}
--- a/beacon-chain/cache/depositcache/deposits_cache_test.go
+++ b/beacon-chain/cache/depositcache/deposits_cache_test.go
--- a/beacon-chain/cache/depositcache/log.go
+++ b/beacon-chain/cache/depositcache/log.go
@@ -1,5 +0,0 @@
-package depositcache
-
-import "github.com/sirupsen/logrus"
-
-var log = logrus.WithField("prefix", "depositcache")
--- a/beacon-chain/cache/depositcache/pending_deposits.go
+++ b/beacon-chain/cache/depositcache/pending_deposits.go
@@ -1,151 +0,0 @@
-package depositcache
-
-import (
-	"context"
-	"math/big"
-	"sort"
-
-	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/client_golang/prometheus/promauto"
-	"github.com/prysmaticlabs/prysm/v5/crypto/hash"
-	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
-	"github.com/sirupsen/logrus"
-	"go.opencensus.io/trace"
-)
-
-var (
-	pendingDepositsCount = promauto.NewGauge(prometheus.GaugeOpts{
-		Name: "beacondb_pending_deposits",
-		Help: "The number of pending deposits in the beaconDB in-memory database",
-	})
-)
-
-// PendingDepositsFetcher specifically outlines a struct that can retrieve deposits
-// which have not yet been included in the chain.
-type PendingDepositsFetcher interface {
-	PendingContainers(ctx context.Context, untilBlk *big.Int) []*ethpb.DepositContainer
-}
-
-// InsertPendingDeposit into the database. If deposit or block number are nil
-// then this method does nothing.
-func (dc *DepositCache) InsertPendingDeposit(ctx context.Context, d *ethpb.Deposit, blockNum uint64, index int64, depositRoot [32]byte) {
-	_, span := trace.StartSpan(ctx, "DepositsCache.InsertPendingDeposit")
-	defer span.End()
-	if d == nil {
-		log.WithFields(logrus.Fields{
-			"block":   blockNum,
-			"deposit": d,
-		}).Debug("Ignoring nil deposit insertion")
-		return
-	}
-	dc.depositsLock.Lock()
-	defer dc.depositsLock.Unlock()
-	dc.pendingDeposits = append(dc.pendingDeposits,
-		&ethpb.DepositContainer{Deposit: d, Eth1BlockHeight: blockNum, Index: index, DepositRoot: depositRoot[:]})
-	pendingDepositsCount.Inc()
-	span.AddAttributes(trace.Int64Attribute("count", int64(len(dc.pendingDeposits))))
-}
-
-// PendingDeposits returns a list of deposits until the given block number
-// (inclusive). If no block is specified then this method returns all pending
-// deposits.
-func (dc *DepositCache) PendingDeposits(ctx context.Context, untilBlk *big.Int) []*ethpb.Deposit {
-	ctx, span := trace.StartSpan(ctx, "DepositsCache.PendingDeposits")
-	defer span.End()
-
-	depositCntrs := dc.PendingContainers(ctx, untilBlk)
-
-	deposits := make([]*ethpb.Deposit, 0, len(depositCntrs))
-	for _, dep := range depositCntrs {
-		deposits = append(deposits, dep.Deposit)
-	}
-
-	return deposits
-}
-
-// PendingContainers returns a list of deposit containers until the given block number
-// (inclusive).
-func (dc *DepositCache) PendingContainers(ctx context.Context, untilBlk *big.Int) []*ethpb.DepositContainer {
-	_, span := trace.StartSpan(ctx, "DepositsCache.PendingDeposits")
-	defer span.End()
-	dc.depositsLock.RLock()
-	defer dc.depositsLock.RUnlock()
-
-	depositCntrs := make([]*ethpb.DepositContainer, 0, len(dc.pendingDeposits))
-	for _, ctnr := range dc.pendingDeposits {
-		if untilBlk == nil || untilBlk.Uint64() >= ctnr.Eth1BlockHeight {
-			depositCntrs = append(depositCntrs, ctnr)
-		}
-	}
-	// Sort the deposits by Merkle index.
-	sort.SliceStable(depositCntrs, func(i, j int) bool {
-		return depositCntrs[i].Index < depositCntrs[j].Index
-	})
-
-	span.AddAttributes(trace.Int64Attribute("count", int64(len(depositCntrs))))
-
-	return depositCntrs
-}
-
-// RemovePendingDeposit from the database. The deposit is indexed by the
-// Index. This method does nothing if deposit ptr is nil.
-func (dc *DepositCache) RemovePendingDeposit(ctx context.Context, d *ethpb.Deposit) {
-	_, span := trace.StartSpan(ctx, "DepositsCache.RemovePendingDeposit")
-	defer span.End()
-
-	if d == nil {
-		log.Debug("Ignoring nil deposit removal")
-		return
-	}
-
-	depRoot, err := hash.Proto(d)
-	if err != nil {
-		log.WithError(err).Error("Could not remove deposit")
-		return
-	}
-
-	dc.depositsLock.Lock()
-	defer dc.depositsLock.Unlock()
-
-	idx := -1
-	for i, ctnr := range dc.pendingDeposits {
-		h, err := hash.Proto(ctnr.Deposit)
-		if err != nil {
-			log.WithError(err).Error("Could not hash deposit")
-			continue
-		}
-		if h == depRoot {
-			idx = i
-			break
-		}
-	}
-
-	if idx >= 0 {
-		dc.pendingDeposits = append(dc.pendingDeposits[:idx], dc.pendingDeposits[idx+1:]...)
-		pendingDepositsCount.Dec()
-	}
-}
-
-// PrunePendingDeposits removes any deposit which is older than the given deposit merkle tree index.
-func (dc *DepositCache) PrunePendingDeposits(ctx context.Context, merkleTreeIndex int64) {
-	_, span := trace.StartSpan(ctx, "DepositsCache.PrunePendingDeposits")
-	defer span.End()
-
-	if merkleTreeIndex == 0 {
-		log.Debug("Ignoring 0 deposit removal")
-		return
-	}
-
-	dc.depositsLock.Lock()
-	defer dc.depositsLock.Unlock()
-
-	cleanDeposits := make([]*ethpb.DepositContainer, 0, len(dc.pendingDeposits))
-	for _, dp := range dc.pendingDeposits {
-		if dp.Index >= merkleTreeIndex {
-			cleanDeposits = append(cleanDeposits, dp)
-		}
-	}
-
-	dc.pendingDeposits = cleanDeposits
-	pendingDepositsCount.Set(float64(len(dc.pendingDeposits)))
-}
--- a/beacon-chain/cache/depositsnapshot/BUILD.bazel
+++ b/beacon-chain/cache/depositsnapshot/BUILD.bazel
@@ -34,6 +34,7 @@ go_test(
    name = "go_default_test",
    srcs = [
        "deposit_cache_test.go",
+        "deposit_fetcher_test.go",
        "deposit_tree_snapshot_test.go",
        "merkle_tree_test.go",
        "spec_test.go",
--- a/beacon-chain/cache/depositsnapshot/deposit_cache_test.go
+++ b/beacon-chain/cache/depositsnapshot/deposit_cache_test.go
@@ -784,7 +784,7 @@ func TestFinalizedDeposits_ReturnsTrieCorrectly(t *testing.T) {
 	depositTrie, err := trie.GenerateTrieFromItems(trieItems, params.BeaconConfig().DepositContractTreeDepth)
 	assert.NoError(t, err)

-	// Perform this in a non-sensical ordering
+	// Perform this in a nonsensical ordering
 	err = dc.InsertFinalizedDeposits(context.Background(), 1, [32]byte{}, 0)
 	require.NoError(t, err)
 	err = dc.InsertFinalizedDeposits(context.Background(), 2, [32]byte{}, 0)
@@ -1189,11 +1189,3 @@ func BenchmarkDepositTree_HashTreeRootOldImplementation(b *testing.B) {
 		require.NoError(b, err)
 	}
 }
-
-func emptyEth1data() *ethpb.Eth1Data {
-	return &ethpb.Eth1Data{
-		DepositRoot:  make([]byte, 32),
-		DepositCount: 0,
-		BlockHash:    make([]byte, 32),
-	}
-}
--- a/beacon-chain/cache/depositsnapshot/deposit_fetcher.go
+++ b/beacon-chain/cache/depositsnapshot/deposit_fetcher.go
@@ -262,6 +262,12 @@ func toFinalizedDepositsContainer(deposits *DepositTree, index int64) finalizedD
 	}
 }

+// PendingDepositsFetcher specifically outlines a struct that can retrieve deposits
+// which have not yet been included in the chain.
+type PendingDepositsFetcher interface {
+	PendingContainers(ctx context.Context, untilBlk *big.Int) []*ethpb.DepositContainer
+}
+
 // PendingDeposits returns a list of deposits until the given block number
 // (inclusive). If no block is specified then this method returns all pending
 // deposits.
--- a/beacon-chain/cache/depositsnapshot/deposit_fetcher_test.go
+++ b/beacon-chain/cache/depositsnapshot/deposit_fetcher_test.go
@@ -1,82 +1,32 @@
-package depositcache
+package depositsnapshot

 import (
 	"context"
 	"math/big"
 	"testing"

-	"github.com/prysmaticlabs/prysm/v5/encoding/bytesutil"
 	ethpb "github.com/prysmaticlabs/prysm/v5/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v5/testing/assert"
-	"google.golang.org/protobuf/proto"
 )

-var _ PendingDepositsFetcher = (*DepositCache)(nil)
+var _ PendingDepositsFetcher = (*Cache)(nil)

 func TestInsertPendingDeposit_OK(t *testing.T) {
-	dc := DepositCache{}
+	dc := Cache{}
 	dc.InsertPendingDeposit(context.Background(), &ethpb.Deposit{}, 111, 100, [32]byte{})

 	assert.Equal(t, 1, len(dc.pendingDeposits), "deposit not inserted")
 }

 func TestInsertPendingDeposit_ignoresNilDeposit(t *testing.T) {
-	dc := DepositCache{}
+	dc := Cache{}
 	dc.InsertPendingDeposit(context.Background(), nil /*deposit*/, 0 /*blockNum*/, 0, [32]byte{})

 	assert.Equal(t, 0, len(dc.pendingDeposits))
 }

-func TestRemovePendingDeposit_OK(t *testing.T) {
-	db := DepositCache{}
-	proof1 := makeDepositProof()
-	proof1[0] = bytesutil.PadTo([]byte{'A'}, 32)
-	proof2 := makeDepositProof()
-	proof2[0] = bytesutil.PadTo([]byte{'A'}, 32)
-	data := &ethpb.Deposit_Data{
-		PublicKey:             make([]byte, 48),
-		WithdrawalCredentials: make([]byte, 32),
-		Amount:                0,
-		Signature:             make([]byte, 96),
-	}
-	depToRemove := &ethpb.Deposit{Proof: proof1, Data: data}
-	otherDep := &ethpb.Deposit{Proof: proof2, Data: data}
-	db.pendingDeposits = []*ethpb.DepositContainer{
-		{Deposit: depToRemove, Index: 1},
-		{Deposit: otherDep, Index: 5},
-	}
-	db.RemovePendingDeposit(context.Background(), depToRemove)
-
-	if len(db.pendingDeposits) != 1 || !proto.Equal(db.pendingDeposits[0].Deposit, otherDep) {
-		t.Error("Failed to remove deposit")
-	}
-}
-
-func TestRemovePendingDeposit_IgnoresNilDeposit(t *testing.T) {
-	dc := DepositCache{}
-	dc.pendingDeposits = []*ethpb.DepositContainer{{Deposit: &ethpb.Deposit{}}}
-	dc.RemovePendingDeposit(context.Background(), nil /*deposit*/)
-	assert.Equal(t, 1, len(dc.pendingDeposits), "deposit unexpectedly removed")
-}
-
-func TestPendingDeposit_RoundTrip(t *testing.T) {
-	dc := DepositCache{}
-	proof := makeDepositProof()
-	proof[0] = bytesutil.PadTo([]byte{'A'}, 32)
-	data := &ethpb.Deposit_Data{
-		PublicKey:             make([]byte, 48),
-		WithdrawalCredentials: make([]byte, 32),
-		Amount:                0,
-		Signature:             make([]byte, 96),
-	}
-	dep := &ethpb.Deposit{Proof: proof, Data: data}
-	dc.InsertPendingDeposit(context.Background(), dep, 111, 100, [32]byte{})
-	dc.RemovePendingDeposit(context.Background(), dep)
-	assert.Equal(t, 0, len(dc.pendingDeposits), "Failed to insert & delete a pending deposit")
-}
-
 func TestPendingDeposits_OK(t *testing.T) {
-	dc := DepositCache{}
+	dc := Cache{}

 	dc.pendingDeposits = []*ethpb.DepositContainer{
 		{Eth1BlockHeight: 2, Deposit: &ethpb.Deposit{Proof: [][]byte{[]byte("A")}}},
@@ -96,7 +46,7 @@ func TestPendingDeposits_OK(t *testing.T) {
 }

 func TestPrunePendingDeposits_ZeroMerkleIndex(t *testing.T) {
-	dc := DepositCache{}
+	dc := Cache{}

 	dc.pendingDeposits = []*ethpb.DepositContainer{
 		{Eth1BlockHeight: 2, Index: 2},
@@ -120,7 +70,7 @@ func TestPrunePendingDeposits_ZeroMerkleIndex(t *testing.T) {
 }

 func TestPrunePendingDeposits_OK(t *testing.T) {
-	dc := DepositCache{}
+	dc := Cache{}

 	dc.pendingDeposits = []*ethpb.DepositContainer{
 		{Eth1BlockHeight: 2, Index: 2},
--- a/beacon-chain/cache/depositsnapshot/deposit_tree.go
+++ b/beacon-chain/cache/depositsnapshot/deposit_tree.go
@@ -15,8 +15,6 @@ import (
 )

 var (
-	// ErrEmptyExecutionBlock occurs when the execution block is nil.
-	ErrEmptyExecutionBlock = errors.New("empty execution block")
 	// ErrInvalidSnapshotRoot occurs when the snapshot root does not match the calculated root.
 	ErrInvalidSnapshotRoot = errors.New("snapshot root is invalid")
 	// ErrInvalidDepositCount occurs when the value for mix in length is 0.
@@ -101,11 +99,23 @@ func (d *DepositTree) getProof(index uint64) ([32]byte, [][32]byte, error) {
 	if d.depositCount <= 0 {
 		return [32]byte{}, nil, ErrInvalidDepositCount
 	}
-	finalizedDeposits, _ := d.tree.GetFinalized([][32]byte{})
-	if finalizedDeposits != 0 {
-		finalizedDeposits = finalizedDeposits - 1
+	if index >= d.depositCount {
+		return [32]byte{}, nil, ErrInvalidIndex
 	}
-	if index <= finalizedDeposits {
+	finalizedDeposits, _ := d.tree.GetFinalized([][32]byte{})
+	finalizedIdx := -1
+	if finalizedDeposits != 0 {
+		fd, err := math.Int(finalizedDeposits)
+		if err != nil {
+			return [32]byte{}, nil, err
+		}
+		finalizedIdx = fd - 1
+	}
+	i, err := math.Int(index)
+	if err != nil {
+		return [32]byte{}, nil, err
+	}
+	if finalizedDeposits > 0 && i <= finalizedIdx {
 		return [32]byte{}, nil, ErrInvalidIndex
 	}
 	leaf, proof := generateProof(d.tree, index, DepositContractDepth)
--- a/beacon-chain/cache/private_access_test.go
+++ b/beacon-chain/cache/private_access_test.go
@@ -0,0 +1,18 @@
+package cache
+
+import (
+	lru "github.com/hashicorp/golang-lru"
+	"github.com/prysmaticlabs/prysm/v5/beacon-chain/state"
+)
+
+func BalanceCacheKey(st state.ReadOnlyBeaconState) (string, error) {
+	return balanceCacheKey(st)
+}
+
+func MaxCheckpointStateSize() int {
+	return maxCheckpointStateSize
+}
+
+func (c *CheckpointStateCache) Cache() *lru.Cache {
+	return c.cache
+}
--- a/beacon-chain/cache/proposer_indices_type.go
+++ b/beacon-chain/cache/proposer_indices_type.go
@@ -1,15 +1,9 @@
 package cache

 import (
-	"errors"
-
 	"github.com/prysmaticlabs/prysm/v5/consensus-types/primitives"
 )

-// ErrNotProposerIndices will be returned when a cache object is not a pointer to
-// a ProposerIndices struct.
-var ErrNotProposerIndices = errors.New("object is not a proposer indices struct")
-
 // ProposerIndices defines the cached struct for proposer indices.
 type ProposerIndices struct {
 	BlockRoot       [32]byte
--- a/beacon-chain/cache/skip_slot_cache.go
+++ b/beacon-chain/cache/skip_slot_cache.go
@@ -109,10 +109,6 @@ func (c *SkipSlotCache) Get(ctx context.Context, r [32]byte) (state.BeaconState,
 // MarkInProgress a request so that any other similar requests will block on
 // Get until MarkNotInProgress is called.
 func (c *SkipSlotCache) MarkInProgress(r [32]byte) error {
-	if c.disabled {
-		return nil
-	}
-
 	c.lock.Lock()
 	defer c.lock.Unlock()

@@ -126,10 +122,6 @@ func (c *SkipSlotCache) MarkInProgress(r [32]byte) error {
 // MarkNotInProgress will release the lock on a given request. This should be
 // called after put.
 func (c *SkipSlotCache) MarkNotInProgress(r [32]byte) {
-	if c.disabled {
-		return
-	}
-
 	c.lock.Lock()
 	defer c.lock.Unlock()

--- a/beacon-chain/cache/skip_slot_cache_test.go
+++ b/beacon-chain/cache/skip_slot_cache_test.go
@@ -2,6 +2,7 @@ package cache_test

 import (
 	"context"
+	"sync"
 	"testing"

 	"github.com/prysmaticlabs/prysm/v5/beacon-chain/cache"
@@ -35,3 +36,28 @@ func TestSkipSlotCache_RoundTrip(t *testing.T) {
 	require.NoError(t, err)
 	assert.DeepEqual(t, res.ToProto(), s.ToProto(), "Expected equal protos to return from cache")
 }
+
+func TestSkipSlotCache_DisabledAndEnabled(t *testing.T) {
+	ctx := context.Background()
+	c := cache.NewSkipSlotCache()
+
+	r := [32]byte{'a'}
+	c.Disable()
+
+	require.NoError(t, c.MarkInProgress(r))
+
+	c.Enable()
+	wg := new(sync.WaitGroup)
+	wg.Add(1)
+	go func() {
+		// Get call will only terminate when
+		// it is not longer in progress.
+		obj, err := c.Get(ctx, r)
+		require.NoError(t, err)
+		require.IsNil(t, obj)
+		wg.Done()
+	}()
+
+	c.MarkNotInProgress(r)
+	wg.Wait()
+}
--- a/Show More
+++ b/Show More
@@ -1 +1 @@
 .0.0
 .1.0