# Progress — Challenger 2

Last visited: 2026-10-04T09:41:00Z
Status: Completed

- [x] Initialized workspace, dispatch, and briefing
- [x] Inspect implementation files: `server/stats/formula_persistence.py`, `server/stats/stat_types.py`, `server/stats/stat_aggregator.py`, `server/world/server_engine_loop.py`
- [x] Inspect existing unit test suite: `tests/unit/test_character_stat_aggregator.py`
- [x] Write empirical stress test harness (`tests/integration/test_formula_persistence_stress.py`) testing:
  - SQLite persistence on disk and in memory
  - High-frequency / concurrent saves
  - JSON AST and final_stats 100% data fidelity on roundtrip
  - ServerEngineLoop.register_player with aggregated stats (> 50.0 attack damage, move_speed sync)
  - ServerEngineLoop.register_player default fallback (50.0 attack damage, 1000.0 HP, 6.0 move_speed)
  - Multi-player isolation under stress
- [x] Execute empirical stress test script via `run_command` (8/8 passed)
- [x] Run regression test suites (41/41 passed) and hygiene audits (100% compliant)
- [x] Document observations, logic chain, caveats, conclusion, and verification method in `handoff.md`
- [x] Issue formal verdict (APPROVE)
- [x] Send completion message to parent