diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index fc0b3505..1d01c612 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -225,6 +225,7 @@ jobs:
     timeout-minutes: 30
     runs-on: ubuntu-latest
     permissions:
+      contents: read
       id-token: write
       attestations: write
     # Requires environment protection rules in GitHub Settings:
@@ -241,5 +242,21 @@ jobs:
       - uses: actions/attest-build-provenance@4d101475d8b20a2381f78447822ac1eab6504dd8 # v4.2.2
         with:
           subject-path: "dist/*"
-      # To upload to PyPI without a token, add this workflow file as a Trusted Publisher in the project settings on the PyPI website
-      - uses: pypa/gh-action-pypi-publish@dc37677b2e1c63e2034f94d8a5b11f265b73ba33 # v1.14.2
+      - name: Authenticate to OSS Exit Gate
+        uses: google-github-actions/auth@7c6bc770dae815cd3e89ee6cdf493a5fab2cc093 # v3.0.0
+        with:
+          workload_identity_provider: 'projects/305452601764/locations/global/workloadIdentityPools/builders/providers/github'
+      - name: Stage package in OSS Exit Gate Artifact Registry
+        run: |
+          python3 -m venv .exit-gate-venv
+          .exit-gate-venv/bin/pip install --upgrade pip keyring twine keyrings.google-artifactregistry-auth
+          .exit-gate-venv/bin/twine upload \
+            --repository-url https://us-python.pkg.dev/oss-exit-gate-prod/s2geometry--pypi \
+            dist/*
+      - name: Trigger OSS Exit Gate release
+        run: |
+          MANIFEST_FILE="$(mktemp)"
+          echo '{"publish_all": true}' > "${MANIFEST_FILE}"
+          gcloud storage cp "${MANIFEST_FILE}" \
+            "gs://oss-exit-gate-prod-projects-bucket/s2geometry/pypi/manifests/manifest-${{ github.run_id }}-${{ github.run_attempt }}.json"
+          rm -f "${MANIFEST_FILE}"