fix: pin reverse-SynthID build and fix Dockerfile ARG scope (#5)

Dockerfile.synthid

@@ -6,10 +6,19 @@
 # The upstream code is fetched from source at build time and is NOT
 # redistributed by this repository. Users must comply with the upstream
 # project's non-commercial Research License.
+#
+# Vendored fork hardening:
+#   - base image pinned by digest (no moving tag drift)
+#   - upstream checkout pinned to a commit SHA (no moving branch)
+#   - deps pinned exactly in requirements-synthid-scorer.txt
 
-FROM python:3.11-slim
+# Pinned upstream commit (2026-07-17). Keep in sync with setup_synthid.sh.
+ARG REVERSE_SYNTHID_REF=b11083676fd3ee3ff97ce9d03c0e409e46905902
 
-ARG REVERSE_SYNTHID_REF=main
+# python:3.11-slim linux/amd64 digest.
+FROM python:3.11-slim@sha256:78b39ef14d8e2b4d71f8dc304f1328c37df95fe0ef99477c2ae6bd3d03784553
+
+ARG REVERSE_SYNTHID_REF
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
@@ -19,9 +28,10 @@ RUN apt-get update \
     && rm -rf /var/lib/apt/lists/*
 
 RUN git clone --depth 1 --filter=blob:none --sparse \
-        --branch "${REVERSE_SYNTHID_REF}" \
         https://github.com/aloshdenny/reverse-SynthID.git /opt/reverse-synthid \
     && cd /opt/reverse-synthid \
+    && git fetch --depth 1 origin "${REVERSE_SYNTHID_REF}" \
+    && git checkout --detach "${REVERSE_SYNTHID_REF}" \
     && git sparse-checkout set --no-cone \
         '/src/' \
         '/artifacts/spectral_codebook_v4.npz' \
@@ -37,4 +47,4 @@ RUN pip install --no-cache-dir -r /app/requirements-synthid-scorer.txt
 ENV REVERSE_SYNTHID_DIR=/opt/reverse-synthid
 
 WORKDIR /app
-ENTRYPOINT ["python3", "/app/score_synthid.py"]
+ENTRYPOINT ["python3", "/app/score_synthid.py"]

skills/remove-ai-marks/scripts/requirements-synthid-scorer.txt

@@ -1,9 +1,13 @@
 # Minimal dependencies for the optional reverse-SynthID pixel scorer.
 # The upstream repo's full requirements.txt adds torch/diffusers and other
 # packages only needed for its VAE/bypass pipeline, which this project does not use.
-numpy>=1.21.0
-scipy>=1.7.0
-opencv-python>=4.5.0
-PyWavelets>=1.1.1
-scikit-learn>=0.24.0
-Pillow>=8.0.0
+#
+# Vendored fork hardening: exact pins (no drift). Re-evaluate versions before
+# bumping and pin the upstream checkout in setup_synthid.sh / Dockerfile.synthid
+# to a matching commit.
+numpy==2.0.2
+scipy==1.14.1
+opencv-python==4.10.0.84
+PyWavelets==1.7.0
+scikit-learn==1.5.2
+Pillow==10.4.0

skills/remove-ai-marks/scripts/setup_synthid.sh

@@ -11,7 +11,8 @@ set -euo pipefail
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 DEFAULT_DIR="${REVERSE_SYNTHID_DIR:-$HOME/reverse-SynthID}"
 DIR=""
-REF="main"
+# Pinned upstream commit (2026-07-17). Do not point at a moving branch.
+REF="b11083676fd3ee3ff97ce9d03c0e409e46905902"
 PYTHON="${PYTHON:-python3}"
 FULL=0
 
@@ -24,7 +25,7 @@ the Python dependencies required by score_synthid.py.
 
 Options:
   --dir PATH     checkout directory (default: $REVERSE_SYNTHID_DIR or ~/reverse-SynthID)
-  --ref REF      git ref to clone (default: main)
+  --ref REF      git ref to checkout (default: pinned commit SHA)
   --full         install upstream requirements.txt (adds torch/diffusers for VAE bypass)
   --python PY    Python interpreter used to create the venv (default: python3)
 EOF
@@ -69,15 +70,22 @@ else
 fi
 
 if [[ ! -d "$DIR/.git" ]]; then
-  echo "Cloning reverse-SynthID into $DIR"
-  git clone --depth 1 --filter=blob:none --sparse --branch "$REF" \
+  echo "Cloning reverse-SynthID into $DIR (pinned ref: $REF)"
+  git clone --depth 1 --filter=blob:none --sparse \
     https://github.com/aloshdenny/reverse-SynthID.git "$DIR"
+  git -C "$DIR" fetch --depth 1 origin "$REF"
+  git -C "$DIR" checkout --detach "$REF"
   git -C "$DIR" sparse-checkout set --no-cone \
     '/src/' \
     '/artifacts/spectral_codebook_v4.npz' \
     '/requirements.txt' \
     '/LICENSE' \
     '/README.md'
+  HEAD_SHA="$(git -C "$DIR" rev-parse HEAD)"
+  if [[ "$HEAD_SHA" != "$REF" ]]; then
+    echo "error: expected pinned ref $REF, got $HEAD_SHA" >&2
+    exit 1
+  fi
 else
   echo "Using existing checkout: $DIR"
 fi