Motivation:

• https://github.com/well-typed/hooks-build-type
• RFC: Replacing the Cabal Custom build-type haskellfoundation/tech-proposals#60
• Haddock documentation for Cabal-3.11.0.0

Currently:

• Stack itself has build type Custom, which makes use of generateBuildModule; and
• Stack uses replHook in StackSetupShim.hs to cause Cabal to create the autogenerated files for every configured component, without building everything, before Stack uses ghc --interactive.

Related question: haskellfoundation/tech-proposals#60 (comment)