# Progress Tracker: Epic 2 — Event Backbone & Durable Store

**Epic:** Epic 2
**Task / Ticket:** Provisioning Core
**Branch:** `feature/epic2-event-backbone-db`
**Base:** `staging`
**Created:** 2026-03-12
**Last Updated:** 2026-03-13 (Bug fix: step label denominator inconsistency)

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## 🎯 Objectives
- [x] Context Scan and Knowledge Item Check
- [x] Schema Analysis (Event Store Table)
- [x] DDD Architectural Design Validation
- [x] Implementation (Migration, Model)
- [x] Infrastructure Audit (GCP Test Env)
- [x] Verification (Load & Stress Validation Script)

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## 🏗️ Technical Context
- **Pattern:** CQRS / Dedicated Durable Store
- **Domain:** `Events`
- **Tables:** `event_store`
- **Dependencies:** GCP Cloud SQL (MySQL 8.x)

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## 📝 Sub-Tasks (TDD Cycle)

| # | Date | Phase | TDD RED / GREEN / REFACTOR | Description | ✅ Done |
|---|------|-------|----------------------------|-------------|---------|
| 1 | 2026-03-12 | Phase 0 | SETUP | Branch and Tracker created | ✅ Done |
| 2 | 2026-03-13 | Phase 0.5 | CONTEXT SCAN | Audited Domain for existing event/sync patterns | ✅ Done |
| 3 | 2026-03-13 | Phase 1/2| DESIGN | Validated Schema and Architectural Design (DDD) | ✅ Done |
| 4 | 2026-03-13 | Phase A | DATABASE | Migration created for `event_store` | ✅ Done |
| 5 | 2026-03-13 | Phase B1 | RED/GREEN/REFACTOR | Implemented `EventStore` model with strict isolation | ✅ Done |
| 6 | 2026-03-13 | Phase Infra | AUDIT | Verified existing `provision_gcp_test_env.sh` covers all backbone requirements | ✅ Done |
| 7 | 2026-03-13 | Phase D | VERIFICATION | Implemented `suitex:test-event-backbone-stress` Artisan command | ✅ Done |
| 6 | 2026-03-26 | Phase D | FIX | PHPStan: Add `@var array<string, mixed>` to `CanonicalEventMapper::buildDataSchema()` — resolves "Cannot unset offset" error | ✅ Done |
| 7 | 2026-03-26 | Phase D | FIX | Test: Namespace `\Domain\Sync\Observers\ProjectObserver` → `\Domain\Sync\Observers\SyncProjectObserver` in `CanonicalEventMapperTest` | ✅ Done |
| 8 | 2026-03-26 | Phase D | FIX | Created missing `SyncProjectObserver.php` in `Domain/Sync/Observers/` with fail-safe `processEvent()` try/catch | ✅ Done |