# 4. Reference (Maintainer Track)

For Java developers maintaining or extending the framework itself.

This chapter is for the people who will modify `BusinessBaseController`, add a new
metadata table to the `gds*` family, or wire in a new third-party integration.

- [The runtime: BusinessBaseController & friends](runtime.md) — the metadata-driven dispatch loop.
- [Generic procedure dispatch](proc-dispatch.md) — `GenericProcedureCallController` deep dive.
- [Cache invalidation on metadata change](cache-invalidation.md) — `ConsumerChangeGdsModuleThread` and friends.
- [SQL templates (`xlyEntry/templesql/`)](sql-templates.md) — runtime SQL generation.
- [Multi-service deployment](deployment.md) — `xlyApi` vs `xlyEntry` vs `xlyInterface`.
- [Activiti integration](activiti.md) — version skew, schemas, custom delegates.

> **STUB.** Each sub-page will be filled with a real code-trace once the matching
> slice exercises it.