From b0696e65df02f57334e07220538538191f5ffdc3 Mon Sep 17 00:00:00 2001
From: hyperpolymath <6759885+hyperpolymath@users.noreply.github.com>
Date: Thu, 25 Jun 2026 09:12:47 +0100
Subject: [PATCH] feat(ci): attest build provenance

Adds actions/attest-build-provenance@v2 (SHA-pinned) after the container
build-push step, with id-token+attestations job permissions and the image
digest captured via the build-push step id. Additive only.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
---
 .github/workflows/publish-container.yml | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/.github/workflows/publish-container.yml b/.github/workflows/publish-container.yml
index 09be35e..236e8b5 100644
--- a/.github/workflows/publish-container.yml
+++ b/.github/workflows/publish-container.yml
@@ -14,6 +14,11 @@ jobs:
   publish:
     runs-on: ubuntu-latest
     timeout-minutes: 15
+    permissions:
+      contents: read
+      packages: write
+      id-token: write       # mint the OIDC token the attestation is signed with
+      attestations: write   # write the build-provenance attestation (the "claim")
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v4
       
@@ -36,6 +41,7 @@ jobs:
             type=sha
       
       - name: Build and push
+        id: push
         uses: docker/build-push-action@f9f3042f7e2789586610d6e8b85c8f03e5195baf # v6
         with:
           context: .
@@ -43,3 +49,10 @@ jobs:
           push: true
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
+
+      - name: Attest container provenance
+        uses: actions/attest-build-provenance@e8998f949152b193b063cb0ec769d69d929409be # v2
+        with:
+          subject-name: ghcr.io/${{ github.repository }}
+          subject-digest: ${{ steps.push.outputs.digest }}
+          push-to-registry: true