I created the jaxb-visitor plugin about 10 years ago for a project working with XML schemas from the Open Geospatial Consortium and recently updated it to work with Java 11 and JAXB 3.

I created asl-path-validator to define the grammar for JSONPath expressions supported by AWS Step Functions. The library validates Path, Reference Path, and Payload Template expressions in Step Functions.

A look at asl-puml and how it emits a PlantUML state diagram from a AWS Step Functions json file.

A compiler plugin to enforce function parameters are either explicitly or effectively final.

Great tip from a colleague for setting up your git repo for git flow.