GHC's project website
Remote debugging for GHC
Nix derivations for various GHC versions.
Infrastructure for testing Hackage packages against GHC pre-releases.
Configuration and documentation for GHC's continuous integration infrastructure.
Scripts and stuff for tracking spurious CI failures in GHC
Utilities I find useful while working on GHC
A QuickCheck testsuite for GHC's C-- pipeline and native code generation backends.