diff --git a/.planning/MILESTONES.md b/.planning/MILESTONES.md
index 0514c6f..e18c434 100644
--- a/.planning/MILESTONES.md
+++ b/.planning/MILESTONES.md
@@ -49,14 +49,19 @@
 
 ---
 
-## v4.0 — Quality Hardening (ACTIVE)
+## v4.0 — Quality Hardening (COMPLETE 2026-06-15)
 
 **Goal:** Close the gap between "tests exist" and "CI actually runs them," fill xUnit coverage across 6 untested states, version the checkpoint schema, and complete portfolio polish.
 
-**Phases:** 17-19 (in progress)
+**Phases:** 17-19
 
-**Target features:**
-- CI runs dotnet test (not just build) + Coverlet coverage badge
-- xUnit tests for Analyzing, Branching, Committing, Documenting, Editing, PrCreating states
-- Checkpoint schema versioning (SchemaVersion field + mismatch guard)
-- GitHub topics on all CAS repos + OgeonX-Ai profile README
+**What shipped:**
+- CI runs `dotnet test` with Coverlet XPlat Code Coverage; results uploaded as artifact
+- README test badge: ![Tests](https://img.shields.io/badge/tests-73%20passing-brightgreen)
+- xUnit tests for all 6 previously untested states: AnalyzingState, BranchingState, EditingState, CommittingState, DocumentingState, PrCreatingState (33 new tests)
+- CheckpointStoreTests: schema compatibility, round-trip, missing-file-returns-null (4 tests)
+- Total test count: 73 (up from 36)
+- `SchemaVersion { get; init; } = "1.0"` added to GsdWorkflowContext
+- FileCheckpointStore.LoadAsync logs warning and returns null on schema version mismatch
+- GitHub topics applied to gsd-orchestrator, Promptimprover, autogen via `gh repo edit`
+- OgeonX-Ai/.github profile README created (commit dd19d55)
diff --git a/.planning/STATE.md b/.planning/STATE.md
index 5a142b0..488beff 100644
--- a/.planning/STATE.md
+++ b/.planning/STATE.md
@@ -3,35 +3,43 @@ gsd_state_version: 1.0
 milestone: v4.0.0
 milestone_name: Quality Hardening
 current_plan: 0
-status: planning
-last_updated: 2026-06-14T00:00:00Z
+status: complete
+last_updated: 2026-06-15T00:00:00Z
 progress:
   total_phases: 3
-  completed_phases: 0
-  total_plans: 0
-  completed_plans: 0
-  percent: 0
-stopped_at: Not started — defining roadmap
+  completed_phases: 3
+  total_plans: 6
+  completed_plans: 6
+  percent: 100
+stopped_at: Milestone complete — v4.0.0 tagged
 ---
 
 # Project State — Quality Hardening (Milestone 4.0)
 
-Last activity: 2026-06-14 — Milestone v4.0 started
+Last activity: 2026-06-15 — Milestone v4.0 complete, v4.0.0 release tagged
 
 ## Current Position
 
-Phase: Not started (defining roadmap)
+Phase: COMPLETE
 Plan: —
-Status: Defining requirements
-Last activity: 2026-06-14 — Milestone v4.0 started
+Status: All 3 phases complete
+Last activity: 2026-06-15 — v4.0.0 GitHub release tagged
 
 ## Current Status
 
 **Active Phase:** —
-**Current Plan:** Not started
-**Last Completed:** Phase 16 — Multi-Repo Support (Milestone 3.0, 2026-06-05)
-**Milestone:** 4.0 — Quality Hardening
-**Last Updated:** 2026-06-14T00:00:00Z
+**Current Plan:** —
+**Last Completed:** Phase 19 — Portfolio Polish (2026-06-15)
+**Milestone:** 4.0 — Quality Hardening (COMPLETE)
+**Last Updated:** 2026-06-15T00:00:00Z
+
+## Milestone 4.0 Phase Progress
+
+| Phase | Name | Status |
+|-------|------|--------|
+| 17 | CI Hardening | complete (2026-06-14) |
+| 18 | State Test Coverage + Checkpoint Versioning | complete (2026-06-14) |
+| 19 | Portfolio Polish | complete (2026-06-15) |
 
 ## Milestone 3.0 Phase Progress
 
@@ -40,8 +48,8 @@ Last activity: 2026-06-14 — Milestone v4.0 started
 | 12 | Robustness Foundation | complete (2026-06-01) |
 | 13 | Smarter Issue Triage | complete (2026-06-02) |
 | 14 | Autonomous Test Generation | complete (2026-06-04) |
-| 15 | PR Review Loop | planned (2026-06-05) |
-| 16 | Multi-Repo Support | planned (2026-06-05) |
+| 15 | PR Review Loop | complete (2026-06-05) |
+| 16 | Multi-Repo Support | complete (2026-06-05) |
 
 ## Phase 12 Plans