# Deterministic Test Harness (Frozen Time, Seeded RNG, Network Isolation)

## Module
AirGap

## Status
VERIFIED

## Description
Deterministic testing infrastructure with frozen time providers, deterministic fixtures, and Testcontainers for PostgreSQL isolation across backend and frontend.

## Implementation Details
- **Test infrastructure**: `src/__Tests/__Libraries/StellaOps.Testing.Chaos/Models.cs` -- chaos/deterministic testing models
- **AirGap tests**: `src/AirGap/__Tests/` -- Controller, Importer, Persistence, Sync, Time tests
- **Frozen time**: `src/AirGap/StellaOps.AirGap.Time/` -- time anchor services with frozen time providers, staleness calculation
- **Time fixtures**: `src/AirGap/StellaOps.AirGap.Time/fixtures/` -- deterministic time test fixtures
- **Testcontainers**: PostgreSQL isolation via `src/AirGap/StellaOps.AirGap.Storage.Postgres.Tests/`
- **Source**: Feature matrix scan

## E2E Test Plan
- [ ] Verify frozen time providers produce deterministic timestamps
- [ ] Test seeded RNG produces reproducible results
- [ ] Verify Testcontainers PostgreSQL isolation works correctly
- [ ] Test deterministic fixtures produce identical outputs across runs

## Verification
- Verified on 2026-02-11 with `run-001`.
- Tier 0 source/declaration checks passed for deterministic harness surfaces across AirGap time fixtures/services, sync fixed-time utilities, persistence postgres fixture/tests, and testing replay/chaos libraries.
- Tier 1 build/tests passed across time/sync/persistence plus testing-chaos/testing-replay projects (`48/48` time tests, `40/40` sync tests, `23/23` persistence tests, `51/51` chaos tests, `20/20` replay tests).
- Tier 2 behavioral checks passed with live `/system/airgap/verify` repeated requests returning byte-identical pass payloads for identical inputs, plus integration evidence for postgres testcontainer isolation and replay harness execution.
- Evidence:
  - `docs/qa/feature-checks/runs/airgap/deterministic-test-harness/run-001/tier0-source-check.json`
  - `docs/qa/feature-checks/runs/airgap/deterministic-test-harness/run-001/tier1-build-check.json`
  - `docs/qa/feature-checks/runs/airgap/deterministic-test-harness/run-001/tier2-api-check.json`