About

Why this playbook exists

Modernisation projects fail not because the patterns are unknown — they fail because the jump from "I understand Strangler Fig" to "I know how to wire this into our Spring Boot codebase" is enormous and under-documented.

I wrote this to close that gap. Every pattern here maps to real code from real projects. The examples are minimal but complete — no hand-waving, no "implementation left as an exercise for the reader".

The companion archetype

This playbook's "after" state is the spring-hexagonal-archetype. Run:

mvn archetype:generate \
  -DarchetypeGroupId=de.marvinrichter \
  -DarchetypeArtifactId=spring-hexagonal-archetype \
  -DarchetypeVersion=LATEST

...to generate a Spring Boot project with the hexagonal structure that the migration patterns in this playbook target.

About the author

I'm Marvin Richter, a software architect based in Berlin. marvin-richter.de →

Contributing

Found an error? Have a pattern to add? Open an issue or send a PR — the docs/ directory is the place to start.