A map of how I actually run backend software: Java on the JVM, Spring as the application layer, Kubernetes as the place it lives. Start here, then open the note that matches the problem in front of you.

This is not a tutorial index. It is the order I would walk a teammate through after an incident.

If you are new here

1. Spring @Transactional does not mean what you think — where transactions actually start, and why a method calling another method on this silently does nothing.
2. Liveness is not health — the Kubernetes outage that looks like a crash loop but started as a slow dependency.
3. Reliability lessons from SQLite — why a tool that solves more problems than it creates stays in production.

The Java course is the longer path if you want to write this stack with me, not only read about it.