diff --git a/.githooks/commit-msg b/.githooks/commit-msg
new file mode 100644
index 0000000..cfe0fdc
--- /dev/null
+++ b/.githooks/commit-msg
@@ -0,0 +1,16 @@
+#!/usr/bin/env sh
+set -eu
+
+message_file="$1"
+tmp_file="${message_file}.tmp"
+
+# Remove auto-injected co-author trailers we do not want in commit history.
+awk '
+{
+  if ($0 ~ /^Co-authored-by:[[:space:]]*Copilot[[:space:]]*<223556219\+Copilot@users\.noreply\.github\.com>[[:space:]]*$/) next
+  if ($0 ~ /^Co-authored-by:[[:space:]]*dexcompiler([[:space:]]*<[^>]+>)?[[:space:]]*$/) next
+  print $0
+}
+' "$message_file" > "$tmp_file"
+
+mv "$tmp_file" "$message_file"
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..df90c05
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,39 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ci-${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: 10.0.x
+
+      - name: Restore
+        run: dotnet restore Clockworks.sln
+
+      - name: Build
+        run: dotnet build Clockworks.sln -c Release --no-restore
+
+      - name: Test
+        run: dotnet test tests/Clockworks.Tests.csproj -c Release --no-build --nologo
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
new file mode 100644
index 0000000..c23189a
--- /dev/null
+++ b/.github/workflows/release.yml
@@ -0,0 +1,99 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - "v*.*.*"
+  workflow_dispatch:
+    inputs:
+      version:
+        description: "Package/release version (e.g. 1.3.1)"
+        required: true
+        type: string
+
+permissions:
+  contents: write
+
+concurrency:
+  group: release-${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: false
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: 10.0.x
+
+      - name: Resolve version
+        id: vars
+        shell: bash
+        run: |
+          if [[ "${{ github.event_name }}" == "workflow_dispatch" ]]; then
+            VERSION="${{ github.event.inputs.version }}"
+            TAG="v${VERSION}"
+          else
+            TAG="${GITHUB_REF_NAME}"
+            VERSION="${TAG#v}"
+          fi
+
+          if [[ ! "${VERSION}" =~ ^[0-9]+\.[0-9]+\.[0-9]+([-+].*)?$ ]]; then
+            echo "Invalid version: ${VERSION}"
+            exit 1
+          fi
+
+          echo "version=${VERSION}" >> "${GITHUB_OUTPUT}"
+          echo "tag=${TAG}" >> "${GITHUB_OUTPUT}"
+
+      - name: Ensure tag exists for manual runs
+        if: github.event_name == 'workflow_dispatch'
+        shell: bash
+        run: |
+          TAG="${{ steps.vars.outputs.tag }}"
+          git fetch --tags --force
+          if ! git rev-parse "${TAG}" >/dev/null 2>&1; then
+            echo "Tag ${TAG} does not exist in repository."
+            echo "Create and push it first (for example: git tag ${TAG} && git push origin ${TAG})."
+            exit 1
+          fi
+
+      - name: Restore
+        run: dotnet restore Clockworks.sln
+
+      - name: Build
+        run: dotnet build Clockworks.sln -c Release --no-restore
+
+      - name: Test
+        run: dotnet test tests/Clockworks.Tests.csproj -c Release --no-build --nologo
+
+      - name: Pack
+        run: >
+          dotnet pack src/Clockworks.csproj
+          -c Release
+          --no-build
+          -p:PackageVersion=${{ steps.vars.outputs.version }}
+          -o artifacts/packages
+
+      - name: Push package to NuGet
+        run: >
+          dotnet nuget push artifacts/packages/*.nupkg
+          --api-key ${{ secrets.NUGET_API_KEY }}
+          --source https://api.nuget.org/v3/index.json
+          --skip-duplicate
+
+      - name: Create GitHub Release
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: ${{ steps.vars.outputs.tag }}
+          generate_release_notes: true
+          files: |
+            artifacts/packages/*.nupkg
+            artifacts/packages/*.snupkg
diff --git a/README.md b/README.md
index f44b3fb..8869a7a 100644
--- a/README.md
+++ b/README.md
@@ -92,13 +92,13 @@ var header = new VectorClockMessageHeader(
     clock: clockA,
     correlationId: Guid.NewGuid()
 );
-var headerString = header.ToString(); // "1:1;{correlationId}" (example)
+var headerString = header.ToString(); // "1:1;{correlationId:N}" (example)
 ```
 
 ### Hybrid Logical Clock (HLC) propagation
 
 In Clockworks, a "remote timestamp" is the `HlcTimestamp` produced on a different node and carried over the wire
-via `HlcMessageHeader` (format: `walltime.counter@node`). The receiver should call `BeforeReceive(...)` with that
+via `HlcMessageHeader` (format: `walltime.counter@node[;correlationId;causationId]`). The receiver should call `BeforeReceive(...)` with that
 timestamp to preserve causality.
 
 Note: `HlcTimestamp.ToPackedInt64()`/`FromPackedInt64()` is an optimization encoding with a 48-bit wall time and a 4-bit node id (node id is truncated). Use `WriteTo`/`ReadFrom` when you need a full-fidelity representation.
@@ -290,6 +290,10 @@ Clockworks follows Semantic Versioning (SemVer).
 - Package version is defined in `src/Clockworks.csproj`.
 - Release tags use the format `vX.Y.Z` (example: `v1.2.0`).
 - See `CHANGELOG.md` for notable changes.
+- CI runs on pushes/PRs to `main` via `.github/workflows/ci.yml`.
+- Publishing is automated by `.github/workflows/release.yml`:
+  - Trigger by pushing a tag like `v1.3.1` to publish to NuGet and create a GitHub Release.
+  - Or run the workflow manually with `version` input (the matching `vX.Y.Z` tag must already exist).
 
 Build-wide defaults are centralized in `Directory.Build.props`.