# AGET v3.9.0 Release Notes

**Release Date**: 2026-03-15
**Theme**: Governance Enforcement — release readiness, version management, process standardization
**Execution**: PROJECT_PLAN_v3.9.0_release_v1.0.md (REL-039)

---

## Executive Summary

AGET v3.9.0 is a governance enforcement release that addresses chronic failure patterns discovered through the Release Lifecycle Model research (L663). Two systemic issues drove this release: **100% post-release failure rate** across 8 formal releases and **version-bearing drift** recurring in every release. Both issues trace to the same root cause — ungoverned transitions between development and release execution.

**Impact**: Agents using v3.9.0 gain:
- Release readiness checklist (Phase -1) that governs the highest failure density zone
- Version bump tooling that covers all 5 artifact types atomically with BLOCKING validation
- Mandatory Gate 0 (Spec Verification) codified in the project plan template
- Deliverable conformance audit (Phase 0.85) as standard release process

**Scope**: 10/10 Tier 1 items delivered (6 implemented + 4 pre-resolved). Tier 2 scope-cut to v3.10.0.

---

## What's New

### Release Readiness Governance (D63 — Gap B)

The Release Lifecycle Model (L663) identified 30 phases across 5 macro-phases, with 3 gap zones. Gap B (Development → Release Execution) had the highest failure density: 12 combined failures, 0 SOP pages, and 100% post-release failure rate.

v3.9.0 adds **Phase -1: Release Readiness** to `SOP_release_process.md` with three sub-phases:

| Phase | Purpose | Checklist Items |
|-------|---------|:---------------:|
| B.1 | Release Readiness Assessment | 5 |
| B.2 | Deliverable Conformance Audit | 4 |
| B.3 | Principal Release Approval | 3 |

**Why it matters**: "Governing the middle while leaving transitions ungoverned is like a bridge with strong spans but no on-ramps" (L663). Phase -1 provides the on-ramp.

**ADR-008 progression**: None → Strict (3-level jump — no prior Advisory layer existed).

### Version-Bearing Enforcement (D64)

Version drift has occurred in every release because `version_bump.py` previously covered only 2 of 5 artifact types. v3.9.0 extends coverage to all 5 types:

| Artifact | Scope | Status |
|----------|-------|:------:|
| `.aget/version.json` | All 13 repos | Was covered |
| `README.md` | 12 templates | Was covered |
| `AGENTS.md` @aget-version | 12 templates | **New** |
| `codemeta.json` | Core only | **New** |
| `CITATION.cff` | Core only | **New** |

New `--check VERSION` mode validates all 27 version-bearing files and returns exit code 1 on any mismatch — making validation BLOCKING in the release process.

**ADR-008 progression**: Advisory → Generator. The tool now enforces what was previously a manual checklist item.

### Process Codification (D39, D40)

Two innovations proven in v3.8.0 are now standard process:

**Gate 0: Spec Verification (MP-1)** — Added to `TEMPLATE_PROJECT_PLAN.md` as a mandatory gate. Every future project plan starts with a spec verification sweep before implementation begins. Includes L611 guidance ("~40% pre-resolved probability" for carry-forward items).

**Phase 0.85: Deliverable Conformance Check** — Added to `SOP_release_process.md` between Phase 0.8 (Verification Logging) and Phase 0.9 (Pre-Release Summary). SHALL violations are BLOCKING.

### Enhance-Spec Tooling (D68, D11)

Fixed two contradictions in `/aget-enhance-spec` skill:
- **#418**: Phase Selection table now includes Phase 6 (Self-Compliance) for all categories — consistent with C3 constraint
- **#419**: Phantom AGET_SKILLS_SPEC reference replaced with SKILL_NAMING_CONVENTION_SPEC

First production exercise completed: WIRE on R-SYNC-001 (4 phases, all PASS).

---

## Pre-Resolved Items (L611 Pattern)

Gate 0 spec verification confirmed 4 of 10 Tier 1 items were already complete — matching the RELEASE_BRIDGE 40% pre-resolved calibration:

| Item | Finding |
|------|---------|
| D16 (Conformance gaps) | 3 methods already implemented in aget_conformance_report.py |
| D24 (PROJECT_PLAN validator) | validate_project_plan.py fully implements R-GOV-PLAN-001/002/003 |
| D25 (Structural Aesthetics) | Principle #3 in DESIGN_PHILOSOPHY.md + MISSION.md |
| D33 (Meta-principles) | GOVERNANCE_PRINCIPLES.md in CLAUDE.md Key Documents + wake_up_ext.py |

**Lesson**: Always verify VERSION_SCOPE items against actual files before scoping (L611).

---

## Tier 2 Scope-Cut

4 items deferred to v3.10.0:
- D3: Skill Customization Detection (P1 — important but complex)
- D17: Session script migration (P2 — 4x deferred)
- D13: Notification validation (P2 — quick win)
- D65: Gap A governance (P2 — scope lock→development transition)

---

## Migration Guide

### For Template Operators

No action required. Version bump is automatic via `version_bump.py --to 3.9.0`.

### For Release Managers

1. **Phase -1 is now required** before entering release execution. Review the 12-item checklist in `SOP_release_process.md`.
2. **`version_bump.py --check`** should be run as a BLOCKING step during Phase 2. It validates all 27 version-bearing files across 13 repos.
3. **Gate 0 is mandatory** in new PROJECT_PLANs. Use the template sweep table to verify specs.

---

## Metrics

| Metric | Value |
|--------|-------|
| Tier 1 items | 10/10 delivered (6 active + 4 pre-resolved) |
| Tier 2 items | 0/4 (scope-cut) |
| BLOCKING V-tests | 23/23 passing (development gates) |
| SHALL violations | 0 (conformance audit) |
| Contract tests | 135 passing |
| Issues closed | #295, #313, #315, #391, #418, #419, #429 |

---

## References

| Document | Purpose |
|----------|---------|
| VERSION_SCOPE_v3.9.0 (v20.0.0) | Scope definition |
| PROJECT_PLAN_v3.9.0_release_v1.0 (v4.0) | Execution plan |
| L663 | Release Lifecycle Model research |
| RELEASE_BRIDGE_v3.8.0_to_next | Velocity calibration |

---

*AGET v3.9.0 — Governance Enforcement*
*"Governing the middle while leaving transitions ungoverned is like a bridge with strong spans but no on-ramps."*
