cgrep 8.0.0/8.1.0 doesn't build

[felixonmars]

[19 of 29] Compiling CGrep.Output     ( src/CGrep/Output.hs, dist/build/cgrep/cgrep-tmp/CGrep/Output.dyn_o )

src/CGrep/Output.hs:173:12: error:
    • Illegal equational constraint GHC.Exts.Item a ~ B.Builder
      (Use GADTs or TypeFamilies to permit this)
    • When checking the inferred type
        mkMatch :: forall {a}.
                   (GHC.Exts.Item a ~ B.Builder, Semigroup a, GHC.Exts.IsList a) =>
                   a -> Output -> a
      In an equation for ‘jsonOutput’:
          jsonOutput outs
            = pure
                $ mconcat . intersperse (B.char8 '\n')
                    $ [B.byteString "{ \"file\":\""
                         <> B.byteString fname <> B.byteString "\", \"matches\":["]
                        <>
                          [mconcat $ intersperse (B.char8 ',') (foldl mkMatch ... outs)]
                            <> [B.byteString "]}"]
            where
                fname | (Output f _ _ _) <- head outs = f
                mkJToken chunk
                  = B.byteString "{ \"col\":"
                      <>
                        B.int64Dec (cOffset chunk)
                          <>
                            B.byteString ", \"token\":\""
                              <> B.byteString (cToken chunk) <> B.byteString "\" }"
                mkMatch xs (Output _ n _ ts) = xs <> [...]
    |
173 |            mkMatch xs (Output _ n _ ts) =
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^...

I'm building with GHC 9.2.8 on Arch Linux x86_64.