diff --git a/docs/roadmap/implementation.md b/docs/roadmap/implementation.md
index 18be867..cad55a2 100644
--- a/docs/roadmap/implementation.md
+++ b/docs/roadmap/implementation.md
@@ -240,6 +240,8 @@ with a normal push; verify remote reachability before Stage 4.
 
 ## Stage 4: Assemble and Validate the Collection
 
+Completion: complete (2026-09-29). Public collection revision: `3d77eb382bcb4c1742015d3c32e23630bb8c73bf`.
+
 ### Required Policy Review
 
 Read `AGENTS.md`, `docs/orientation.md`, `docs/conventions.md`,