Supporting a new language in ReSharper

Hi, im trying to support a new c-like language for Rider and Resharper. With the existing documentation and examples from similar plugins like Unity support, F# support i was able to create a Lexer with the help of CsLex, however now i am finding it hard to correctly create a .psi file for the creation of the parser with ParserGen.

The existing documentation references an example plugin called PsiPlugin, however i can’t find it anywhere. The documentation also hasn’t been updated in 3 years, so a lot of things there are outdated as well or greyed out for later documentation.

Maybe there is some internal documentation that you can share on the structure of the .psi files? That would help a lot!