A three-layer regression-protection stack for AI-built codebases that ship fast across many small fixes. Designed for projects where:
- Releases are frequent (daily alphas, not monthly majors)
- Fixes are small (one-line CLI parser swaps, dependency moves) but many in number
- Multiple agents touch overlapping code in the same release window
- A regression that ships affects every user immediately, not just one customer
The stack catches three distinct regression classes that traditional CI misses, then provides forensic tools to answer "when did this break and what changed?"