diff --git a/.github/actions/avalanchego-setup-action/README.md b/.github/actions/avalanchego-setup-action/README.md
new file mode 100644
index 000000000000..a561cf1b8d4a
--- /dev/null
+++ b/.github/actions/avalanchego-setup-action/README.md
@@ -0,0 +1,44 @@
+# AvalancheGo Setup Action
+
+## Overview
+This action provides composable CI capabilities for setting up AvalancheGo with custom dependency versions.
+
+### Why this exists?
+Solves CI composability problems by enabling repositories to setup and build AvalancheGo with specific dependency versions without complex setup or cross-repository coordination.
+
+### Why is it needed?
+Dependencies need AvalancheGo as their integration context for realistic testing.
+Without this action, setting up AvalancheGo with custom dependency versions requires build knowledge and manual `go mod` manipulation.
+Teams either skip proper testing or dump tests in AvalancheGo (wrong ownership).
+This action makes AvalancheGo composable - any repository can pull it in as integration context with one line.
+
+## Security Model
+- Repository Restriction: Only allows dependencies from `github.com/ava-labs/*` repositories
+- No Custom Forks: Prevents supply chain attacks from malicious forks
+- Commit Validation: Validates dependency versions reference ava-labs repositories only
+
+## Inputs
+
+| Input | Description | Required | Default               |
+|-------|-------------|----------|-----------------------|
+| `checkout-path` | Directory path where AvalancheGo will be checked out | No | `'.'`                 |
+| `avalanchego` | AvalancheGo version (commit SHA, branch, tag) | No | `'${{ github.sha }}'` |
+| `firewood` | Firewood version. Consumer should run Firewood shared workflow first | No | `''`                  |
+| `coreth` | Coreth version (commit SHA, branch, tag) | No | `''`                  |
+| `libevm` | LibEVM version (commit SHA, branch, tag) | No | `''`                  |
+
+## Usage Examples
+
+```yaml
+- name: Setup AvalancheGo with Firewood             # This will setup go.mod
+  uses: ./.github/actions/avalanchego-setup-action
+  with:
+    checkout-path: "build/avalanchego"
+    coreth: "my-feature-branch"
+    libevm: "experimental-branch"
+    firewood: "ffi/v0.0.12"
+- name: Load test                                   # This will compile and run the load test
+  uses: ./.github/actions/run-monitored-tmpnet-cmd
+  with:
+      run: ./scripts/run_task.sh test-load -- --load-timeout=30m --firewood
+```
diff --git a/.github/actions/avalanchego-setup-action/action.yml b/.github/actions/avalanchego-setup-action/action.yml
new file mode 100644
index 000000000000..1ce539fc2b28
--- /dev/null
+++ b/.github/actions/avalanchego-setup-action/action.yml
@@ -0,0 +1,61 @@
+name: 'Setup AvalancheGo'
+description: 'Setup AvalancheGo with custom dependencies (Firewood, Coreth, LibEVM)'
+
+inputs:
+  avalanchego:
+    description: 'AvalancheGo version (commit SHA, branch name, or tag)'
+    required: false
+    default: ${{ github.sha }}
+  checkout-path:
+    description: 'Path where AvalancheGo will be checked out'
+    required: false
+    default: '.'
+  firewood:
+    description: 'Firewood version (commit SHA, branch, tag, or ffi/vX.Y.Z for pre-built)'
+    required: false
+    default: ''
+  firewood-path:
+    description: 'Directory path where Firewood will be cloned/built (preferably NVMe storage)'
+    required: false
+    default: ''
+  coreth:
+    description: 'Coreth version (commit SHA, branch name, or tag)'
+    required: false
+    default: ''
+  libevm:
+    description: 'LibEVM version (commit SHA, branch name, or tag)'
+    required: false
+    default: ''
+
+runs:
+  using: 'composite'
+  steps:
+    - name: Checkout AvalancheGo
+      uses: actions/checkout@v4
+      with:
+        repository: 'ava-labs/avalanchego'
+        ref: ${{ inputs.avalanchego }}
+        path: ${{ inputs.checkout-path }}
+    - name: Update Coreth dependency
+      if: inputs.coreth != ''
+      shell: bash
+      working-directory: ${{ inputs.checkout-path }}
+      run: |
+        echo "Updating Coreth to version: ${{ inputs.coreth }}"
+        go get github.com/ava-labs/coreth@${{ inputs.coreth }}
+    - name: Update LibEVM dependency
+      if: inputs.libevm != ''
+      shell: bash
+      working-directory: ${{ inputs.checkout-path }}
+      run: |
+        echo "Updating LibEVM to version: ${{ inputs.libevm }}"
+        go get github.com/ava-labs/libevm@${{ inputs.libevm }}
+    - name: Setup Firewood FFI
+      if: inputs.firewood != ''
+      shell: bash
+      run: |
+        if [ -n "${{ inputs.firewood-path }}" ]; then
+          "${{ inputs.checkout-path }}/scripts/setup_firewood.sh" "${{ inputs.firewood }}" "${{ inputs.firewood-path }}"
+        else
+          "${{ inputs.checkout-path }}/scripts/setup_firewood.sh" "${{ inputs.firewood }}"
+        fi
diff --git a/Taskfile.yml b/Taskfile.yml
index 962deb68d583..50f62f8e917b 100644
--- a/Taskfile.yml
+++ b/Taskfile.yml
@@ -11,6 +11,12 @@ tasks:
     desc: Builds avalanchego
     cmd: ./scripts/build.sh
 
+  build-with-firewood:
+    desc: Builds avalanchego with Firewood FFI (specify version with FIREWOOD_VERSION)
+    vars:
+      FIREWOOD_VERSION: '{{.FIREWOOD_VERSION | default "ffi/v0.0.12"}}'
+    cmd: ./scripts/build.sh -f {{.FIREWOOD_VERSION}}
+
   build-antithesis-images-avalanchego:
     desc: Builds docker images for antithesis for the avalanchego test setup
     env:
diff --git a/scripts/build.sh b/scripts/build.sh
index 9ca888030cd0..d5df89a00a04 100755
--- a/scripts/build.sh
+++ b/scripts/build.sh
@@ -9,19 +9,29 @@ print_usage() {
 
   Options:
 
-    -r  Build with race detector
+    -r              Build with race detector
+    -f VERSION      Build with Firewood FFI
+                    VERSION format: ffi/vX.Y.Z for pre-built, commit/branch for source
 "
 }
 
 race=''
-while getopts 'r' flag; do
+firewood_version=''
+
+while getopts 'rf:' flag; do
   case "${flag}" in
     r)
       echo "Building with race detection enabled"
       race='-race'
       ;;
-    *) print_usage
-      exit 1 ;;
+    f)
+      firewood_version="${OPTARG}"
+      echo "Building with Firewood version: ${firewood_version}"
+      ;;
+    *)
+      print_usage
+      exit 1
+      ;;
   esac
 done
 
@@ -31,6 +41,10 @@ source "${REPO_ROOT}"/scripts/constants.sh
 # Determine the git commit hash to use for the build
 source "${REPO_ROOT}"/scripts/git_commit.sh
 
+if [ -n "${firewood_version}" ]; then
+  "${REPO_ROOT}/scripts/setup_firewood.sh" "${firewood_version}" "${REPO_ROOT}"
+fi
+
 echo "Building AvalancheGo with [$(go version)]..."
 go build ${race} -o "${avalanchego_path}" \
    -ldflags "-X github.com/ava-labs/avalanchego/version.GitCommit=$git_commit $static_ld_flags" \
diff --git a/scripts/setup_firewood.sh b/scripts/setup_firewood.sh
new file mode 100755
index 000000000000..7cf55f63267d
--- /dev/null
+++ b/scripts/setup_firewood.sh
@@ -0,0 +1,77 @@
+#!/usr/bin/env bash
+
+# Setup Firewood FFI
+#
+# Clones Firewood repository, builds/fetches the FFI, and updates go.mod
+#
+# Usage:
+#   setup_firewood.sh <version> [workspace]
+#
+# Arguments:
+#   version       Firewood version (ffi/vX.Y.Z for pre-built, commit/branch for source)
+#   workspace     Optional workspace path for Firewood build (default: ${AVALANCHE_PATH}/firewood-workspace)
+#
+# Output:
+#   Prints FFI path to stdout on success
+
+set -euo pipefail
+
+if [ $# -lt 1 ]; then
+    echo "Usage: $0 <version> [workspace]" >&2
+    exit 1
+fi
+
+FIREWOOD_VERSION="$1"
+AVALANCHE_PATH=$( cd "$( dirname "${BASH_SOURCE[0]}" )"; cd .. && pwd )
+FIREWOOD_CLONE_DIR="${AVALANCHE_PATH}/firewood"
+
+# Use provided workspace or default to avalanchego/firewood-workspace
+if [ $# -ge 2 ] && [ -n "$2" ]; then
+    WORKSPACE_PATH="$2"
+else
+    WORKSPACE_PATH="${AVALANCHE_PATH}/firewood-workspace"
+fi
+
+if [ -d "${FIREWOOD_CLONE_DIR}" ]; then
+  echo "Removing existing Firewood directory..." >&2
+  rm -rf "${FIREWOOD_CLONE_DIR}"
+fi
+
+echo "Setting up Firewood FFI version: ${FIREWOOD_VERSION}" >&2
+echo "Using workspace: ${WORKSPACE_PATH}" >&2
+
+git clone https://github.com/ava-labs/firewood "${FIREWOOD_CLONE_DIR}" \
+  --quiet --depth 1 --branch composable-ci-action
+
+SETUP_FIREWOOD_SCRIPT="${FIREWOOD_CLONE_DIR}/benchmark/setup-scripts/build-firewood.sh"
+
+if [ ! -f "${SETUP_FIREWOOD_SCRIPT}" ]; then
+  echo "Error: Setup Firewood script not found at ${SETUP_FIREWOOD_SCRIPT}" >&2
+  exit 1
+fi
+
+# Build or fetch Firewood FFI with custom workspace
+# Capture only the last line which is the FFI path
+FFI_PATH=$("${SETUP_FIREWOOD_SCRIPT}" "${FIREWOOD_VERSION}" --workspace "${WORKSPACE_PATH}" | tail -n 1)
+
+if [ -z "${FFI_PATH}" ]; then
+  echo "Error: Failed to build/fetch Firewood FFI" >&2
+  exit 1
+fi
+
+cd "${AVALANCHE_PATH}"
+
+# Verify go.mod exists
+if [ ! -f "go.mod" ]; then
+  echo "Error: go.mod not found in ${AVALANCHE_PATH}" >&2
+  exit 1
+fi
+
+echo "Updating go.mod with FFI path: ${FFI_PATH}" >&2
+go mod edit -replace github.com/ava-labs/firewood-go-ethhash/ffi="${FFI_PATH}"
+
+go mod tidy
+go mod download
+
+# Output FFI path to stdout for consumption by other scripts
+echo "${FFI_PATH}"