Yeah, pfff seems very cool. It seems that pfff has written parsers and type inferencers for a variety of languages in OCaml. That is an impressive achievement.
For srclib, we are way lazier. We try to use existing libraries (written in the languages they target) for parsing, type checking/inference, dependency resolution, etc. We hope that makes it easier for JavaScript hackers to hack on srclib's JavaScript support, Python hackers to work on srclib's Python support, etc.
Yes, lately I've also tried to reuse existing "parsers" ... for instance I now use existing libraries for the java bytecode, ocaml typed AST (.cmt) and clang ASTs.
For srclib, we are way lazier. We try to use existing libraries (written in the languages they target) for parsing, type checking/inference, dependency resolution, etc. We hope that makes it easier for JavaScript hackers to hack on srclib's JavaScript support, Python hackers to work on srclib's Python support, etc.