diff --git a/docs/docker-build-optimization-roadmap.md b/docs/docker-build-optimization-roadmap.md
index d432597..7d36e67 100644
--- a/docs/docker-build-optimization-roadmap.md
+++ b/docs/docker-build-optimization-roadmap.md
@@ -266,7 +266,7 @@ curl -sS http://host.docker.internal:3300/api/v1/version
   ```
 - [ ] **A2-3.** Verify cache mount is active: `docker buildx du --filter type=exec.cachemount` shows non-zero size after a build. **Real success metric** is wall-clock: warm rebuild (touching one source file) drops to < 30 s.
 
-### A3. Decide lockfile policy (BLOCKED on F2 resolution)
+### A3. Decide lockfile policy ✅ DONE (ADR-0001)
 
 Two options — pick one in a short ADR before implementing:
 
@@ -280,8 +280,8 @@ Two options — pick one in a short ADR before implementing:
   - ❌ New build step + tooling
   - ❌ Drift risk between dev lockfile and Docker lockfile
 
-- [ ] **A3-1.** Write 1-page ADR (`docs/decisions/0001-docker-lockfile-policy.md`) and pick Option 1 or 2
-- [ ] **A3-2.** Defer `--frozen-lockfile` adoption until ADR lands
+- [x] **A3-1.** ADR written: [`docs/adr/0001-docker-build-lockfile-policy.md`](./adr/0001-docker-build-lockfile-policy.md) — **Option 1 accepted** (keep `--lockfile=false` short-term; revisit after Phase D).
+- [x] **A3-2.** `--frozen-lockfile` adoption deferred per ADR; tracked as future work in §11.
 
 ### A4. Restructure layer order