Bazel, Cabal, Stack: Why choose when you can have them all? - Tweag

submited by

Style Pass

2024-09-23 03:30:02

No new product created in Haskell ever starts from scratch. Hackage hosts millions of lines of third-party code, neatly and independently redistributable as Cabal packages. Now, Bazel has native support for building Cabal packages since the 0.10 release of rules_haskell.

Cabal packages themselves seldom start from scratch. That’s why packages typically have dozens of dependencies. Resolving version bounds declared for all dependencies in the package metadata to a set of concrete versions, and then downloading these dependencies, is a painstaking task if done manually. Bazel can now use Stack to do this all automatically—the user only needs to provide the name of a Stackage snapshot and the names of the packages they want to reuse for their project.

Users frequently ask which build tool to use for their next project. It turns out that “all of them at once” is a compelling answer (including Nix, though we covered that previously and won’t be rehearsing that in this post).