# Rat Stack systems

The systems rat-stack ships. Each page says what the system does, the standard it keeps, and how to check that standard.

- [Analytics](/systems/analytics) — One event per HTTP request, stored unchanged in an Iceberg table on R2 and shaped at query time.
- [Auth](/systems/auth) — Email and password sign-in through Better Auth, with the signed-in person provided to each RPC call.
- [Capabilities](/systems/capabilities) — Every route, tool, and command rat-stack serves comes from one schema-typed contract and one handler.
- [Database](/systems/database) — A run log behind one service, stored in Cloudflare D1 or in Postgres through Hyperdrive, chosen by one vendor value.
- [Fence](/systems/fence) — The lint rules, compiler diagnostics, hooks, and gate that make a bad shortcut fail instead of asking an agent to avoid it.