Letting AI safely operate a million-line legacy estate
- What
- A federated control plane that lets AI agents read and reason over an 8-application, ~1.78M-line polyglot legacy estate (PHP, Laravel, iOS, Android) without ever breaking it.
- Hard problem
- Turning an un-editable, multi-decade brownfield — the kind that defeats whole teams — into something an AI can work over safely.
- Approach
- Tiered permissions (some repos read-only, some guarded-edit), a typed hook-event boundary grounded in real payloads, a fail-closed sentinel gate, and a control↔contract meta-test that refuses to ship a guard it can’t prove fires. Nine MCP code-graph servers over the estate.
- Result
- Agents operate the estate safely, with a complete, tamper-evident audit trail of everything they do.