Nixpkgs version

• Unstable (25.05)

Describe the bug

In haskell-updates branch, nix-build -A haskellPackages.hledger-lib fails with:

megaparsec >=7.0.0 && <9.7

The reason is that hledger-lib depends on "megaparsec" but megaparsec is at version 9.7 in this branch and hledger-lib requires a version strictly lower than that. Even though hackage-packages.nix indicates that megaparsec is at version 9.6.1:

{
  "megaparsec" = callPackage
    ({ mkDerivation, base, bytestring, case-insensitive, containers
     , criterion, deepseq, mtl, parser-combinators, scientific, text
     , transformers, weigh
     }:
     mkDerivation {
       pname = "megaparsec";
       version = "9.6.1";
     });
}

configuration-ghc-9.8.x overrides that:

{
  megaparsec = doDistribute self.megaparsec_9_7_0;
}

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@NixOS/haskell

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