Undocumented in public but I’m sure you could ask the right colleagues internally :) https://github.com/google/turbine

This is interesting, but has little documentation. @Zac Sweers Could I get a TLDR on what this does?

basically creates stub jars with signatures only

Oh huh interesting. So this is separate than say a traditional API jar with interfaces only?

same idea but could include non-public API

It's even better than just not implemented. Because it only has to parse signatures and not method bodies the stub jar can be made available before the regular jar. This means downstream dependencies can start compiling before you're done fully compiling upstream deps.