Completely refactored the entire backend, fixed hundreds of bugs, stabilised the codebase, and made the code much clearer. Added SonarCloud integrations to the pipelines, fixing hundreds of code smells, increased coverage from 20-40% to more than 90% on most projects, and basically (almost) completely rewritten the entire thing.
Improved documentation on all sub-projects that previously missed such, and made all projects much more adaptable, allowing you to inject custom logic, every place this makes sense - Such as in the expression iterators, type conversions, etc.
Probably improved quality of the entire thing by an order of magnitude.