ci: OSSF scorecard hardening (DPLAN-0243) — hash-pin all standalone workflow pip installs via .github/requirements/ locks (pip/lint/build/e2e/audit, pip-compile --generate-hashes, 11/11 target-env closure verified incl. Windows colorama marker fix) + provenance attestation on publish (attest-build-provenance v4.1.1 SHA-pinned, id-token+attestations perms) + dependabot pip ecosystem for the new locks. Editable -e . installs untouched byte-identical. 5/5 fresh-venv --require-hashes installs green, 5/5 YAML parse, pinned ruff matches repo lint. First SSH-signed commit (repo config wired this session).

.github/workflows/ci.yml

@@ -20,7 +20,9 @@ jobs:
       - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
         with:
           python-version: "3.13"
-      - run: pip install ruff
+      # Hash-pinned tool install (Scorecard: Pinned-Dependencies). Pins ruff to
+      # the version this lint gate is known-green against; see .github/requirements/lint.in.
+      - run: python -m pip install --require-hashes -r .github/requirements/lint.txt
       - run: ruff check src/ tests/
       - run: ruff format --check src/ tests/
 
@@ -36,7 +38,7 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
       - run: |
-          python -m pip install --upgrade pip
+          python -m pip install --require-hashes -r .github/requirements/pip.txt
           pip install -e ".[dev]"
       # tests/e2e build a wheel + clean venv per the dedicated e2e-wheel.yml
       # workflow — they are not part of the fast unit lane.
@@ -57,7 +59,7 @@ jobs:
         with:
           python-version: "3.13"
       - run: |
-          python -m pip install --upgrade pip
+          python -m pip install --require-hashes -r .github/requirements/pip.txt
           # Install the `memory` extra (numpy/chromadb/fastembed) alongside dev:
           # the diagnostics standard runs pyright over every branch, and memory's
           # handlers import chromadb/numpy. Without these deps installed, pyright
@@ -79,7 +81,7 @@ jobs:
         with:
           python-version: "3.13"
       - run: |
-          python -m pip install --upgrade pip
+          python -m pip install --require-hashes -r .github/requirements/pip.txt
           pip install -e ".[dev]"
       - run: coverage run -m pytest --rootdir=. --ignore=tests/e2e
       - run: coverage xml

.github/workflows/e2e-wheel.yml

@@ -47,7 +47,14 @@ jobs:
           python-version: ${{ matrix.python-version }}
 
       - name: Install build tooling
-        run: python -m pip install --upgrade pip build pytest
+        # Hash-pinned (Scorecard: Pinned-Dependencies). e2e.txt carries colorama
+        # explicitly — build/pytest need it only on Windows (os_name == "nt" /
+        # sys_platform == "win32"), and a Linux-generated lock would otherwise
+        # omit it and break the windows-latest leg under --require-hashes.
+        # See .github/requirements/e2e.in.
+        run: |
+          python -m pip install --require-hashes -r .github/requirements/pip.txt
+          python -m pip install --require-hashes -r .github/requirements/e2e.txt
 
       - name: Run cross-OS e2e wiring harness
         # conftest.py builds the wheel + clean venv internally; the outer env

.github/workflows/publish.yml

@@ -11,13 +11,34 @@ permissions:
 jobs:
   build:
     runs-on: ubuntu-latest
+    # Job-level permissions REPLACE the top-level block rather than merge with
+    # it, so `contents: read` is restated here on purpose — dropping it would
+    # break actions/checkout. id-token/attestations are what the provenance
+    # attestation below needs (Scorecard: Signed-Releases).
+    permissions:
+      contents: read
+      id-token: write
+      attestations: write
     steps:
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
       - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1 # v6.3.0
         with:
           python-version: "3.13"
-      - run: pip install build
+      # Hash-pinned tool install (Scorecard: Pinned-Dependencies).
+      - run: python -m pip install --require-hashes -r .github/requirements/build.txt
       - run: python -m build
+      - name: Attest build provenance
+        # Signs a provenance statement binding these exact sdist/wheel digests to
+        # this workflow run, via the same keyless Sigstore/OIDC path as the
+        # release signing below. Runs after the artifacts exist and before they
+        # leave the job, so the attested digests are the published ones.
+        # NOTE: the bundle is deliberately NOT written into dist/ — the publish
+        # job feeds dist/* to gh-action-pypi-publish, which rejects any file that
+        # is not a distribution. See the report note on attaching provenance to
+        # the GitHub Release.
+        uses: actions/attest-build-provenance@0f67c3f4856b2e3261c31976d6725780e5e4c373 # v4.1.1
+        with:
+          subject-path: "dist/*"
       - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
         with:
           name: dist

.github/workflows/security.yml

@@ -27,9 +27,11 @@ jobs:
       # 26.1.2). Upgrading removes the vulnerable version outright rather than
       # suppressing it — and 26.1.2 also resolves CVE-2026-3219 / CVE-2026-6357,
       # which is why those two stale --ignore-vuln entries are no longer needed.
+      # Both installs are hash-pinned (Scorecard: Pinned-Dependencies); pip.txt
+      # holds the >=26.1.2 floor the comment above requires.
       - run: |
-          python -m pip install --upgrade pip
-          pip install pip-audit
+          python -m pip install --require-hashes -r .github/requirements/pip.txt
+          python -m pip install --require-hashes -r .github/requirements/audit.txt
       - run: pip install -e .
       - name: Pip audit
         run: pip-audit --skip-editable