diff --git a/.woodpecker/main.yaml b/.woodpecker/main.yaml
index cefe6e2..c8b151b 100644
--- a/.woodpecker/main.yaml
+++ b/.woodpecker/main.yaml
@@ -11,19 +11,21 @@ services:
 
 steps:
   - name: test-UTs-n-ITs
-    image: python:3.13-slim
+    image: gitea.earthmanrpg.me/discoman/python-tdd-ci:latest
     environment:
       DATABASE_URL: postgresql://postgres:postgres@postgres/python_tdd_test
       CELERY_BROKER_URL: redis://redis:6379/0
       REDIS_URL: redis://redis:6379/1
-      # Workspace-shared pip cache — Woodpecker mounts the workspace across
-      # all steps in a run, so the wheels populated here are reused by
-      # test-two-browser-FTs + test-FTs (saves ~30-60s × 2 = ~1-2 min per
-      # run). Cache lives only inside one run; cross-run caching would
-      # need a volume plugin.
       PIP_CACHE_DIR: .pip-cache
     commands:
-      - pip install -r requirements.txt
+      # `requirements.dev.txt` is the pinned superset Dockerfile.ci pre-
+      # installs; pinning here means pip skips resolver+download and just
+      # verifies "already satisfied" (~5-10s) instead of resolving unpinned
+      # requirements.txt against PyPI from scratch (~30-60s). Drift safety
+      # net: if requirements.dev.txt has changed since the CI image was
+      # last rebuilt + pushed, pip installs the delta — slower for that
+      # run but never broken. See TDD SKILL.md § CI dependency discipline.
+      - pip install -r requirements.dev.txt
       - cd ./src
       - python manage.py test apps
     when:
@@ -45,7 +47,7 @@ steps:
         from_secret: stripe_publishable_key
       PIP_CACHE_DIR: .pip-cache
     commands:
-      - pip install -r requirements.txt
+      - pip install -r requirements.dev.txt
       - cd ./src
       - python manage.py collectstatic --noinput
       - python manage.py test functional_tests --tag=two-browser
@@ -70,7 +72,7 @@ steps:
         from_secret: stripe_publishable_key
       PIP_CACHE_DIR: .pip-cache
     commands:
-      - pip install -r requirements.txt
+      - pip install -r requirements.dev.txt
       - cd ./src
       - python manage.py collectstatic --noinput
       - python manage.py test functional_tests --parallel --exclude-tag=channels --exclude-tag=two-browser