Enforce that there are no warnings in our haskell code#390
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There should be no change in behavior here. I had to upgrade our `cabal-version` to get support for common stanzas: ``` Warning: nixfmt.cabal:63:3: Unknown field: import. You should set cabal-version: 2.2 or larger to use common stanzas ``` I picked the newest version from <https://cabal.readthedocs.io/en/stable/file-format-changelog.html> that our version of cabal supports.
We had a bunch of warnings enabled, but the build would still succeed if any of them fired. Now we have a project wide `werror` flag which determines whether or not these warnings are fatal (IIUC, this is best practice in the haskell ecosystem, as others may want to build your project with a different version of ghc, which may emit different warnings.
This should give the best experience for new contributors, along with a documented escape hatch for experienced contributors. See discussion here: <NixOS#390 (comment)>
dyegoaurelio
approved these changes
May 20, 2026
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(There are multiple commits in here, I suggest reading them separately)
We had a bunch of warnings enabled, but the build would still succeed if
any of them fired. Now we have a project wide
werrorflag whichdetermines whether or not these warnings are fatal (IIUC, this is best
practice in the haskell ecosystem, as others may want to build your
project with a different version of ghc, which may emit different
warnings.