As I mentioned to a few people recently, I wanted to explore replacing Hadrian with Buck2. I've got a prototype to the point where it can build the stage2 compiler and all the libraries on Linux:
buck2 run :stage2-ghc -- --interactive GHCi, version 10.1.20261017: https://www.haskell.org/ghc/ :? for help Using default language edition: GHC2024 ghci> 1+2 3 ghci>
This includes dynamic/static, all the RTS ways and profiling is allegedly working although I haven't tested it very much. It's a LOT smaller than Hadrian - hard to say exactly how much because some of the code is in the shared projects cabal-buck2 and haskell-buck2, but there's about 1400 lines of Buck2 stuff in the ghc repo and nothing in the library submodules. I've written up the design along with some notes on how to set it up and try it over here: https://github.com/simonmar/ghc/blob/buck2/README.buck2.md Keen to hear what people think about this. Are there key metrics that we should measure to understand whether it's better than Hadrian? What are the workflow aspects that people find slow currently? Cheers Simon