Hi Could anyone explain this to me, please? $ cabal install snap-server-0.9.5.1 Resolving dependencies... Configuring snap-server-0.9.5.1... cabal: At least the following dependencies are missing: attoparsec >=0.10 && <0.13 && ==0.13.0.1 cabal: Error: some packages failed to install: snap-server-0.9.5.1 failed during the configure step. The exception was: ExitFailure 1 Where does this unsatisfiable dependency come from? snap-server-0.9.5.1 seems to require just attoparsec (>=0.10 && <0.14): http://hackage.haskell.org/package/snap-server-0.9.5.1 . And attoparsec 0.13.0.1 is already installed: $ cabal list --installed attoparsec * attoparsec Synopsis: Fast combinator parsing for bytestrings and text Default available version: 0.13.0.1 Installed versions: 0.13.0.1 Homepage: https://github.com/bos/attoparsec License: BSD3 * attoparsec-enumerator Synopsis: Pass input from an enumerator to an Attoparsec parser. Default available version: 0.3.4 Installed versions: 0.3.4 Homepage: https://john-millikin.com/software/attoparsec-enumerator/ License: MIT I am trying to install hakyll 4.6.*, and snap-server seems to be one of the requirements. Hakyll 4.6.* is an old version but AFAIR I need that due to conflicting versions of containers. Thanks! -- http://people.eisenbits.com/~stf/ http://www.eisenbits.com/ OpenPGP: 9EC2 5620 2355 B1DC 4A8F 8C79 0EC7 C214 E5AE 3B4E