⭐ Architecture Overview

The module map, the two transports (gRPC + Kafka), and how the one entry point fits together are covered in the system-architecture.html diagram, rather than repeated here.

One thing the diagram doesn't have room for: the real bugs found by actually running this repo, not by reading it. The two biggest — spring-grpc's BOM silently downgrading protobuf-java below what generated code needs on the real runtime classpath, and Spring Boot 3.4.1 being unable to boot at all under JDK 25 — are both covered on the Testing Strategy page, since both were only caught by a specific test layer, not by inspection.

Full decision-by-decision reasoning (context, alternatives, consequences) lives in docs/architecture.md in the repo — this page and the diagram summarize it, not duplicate it.