Resolving dependencies...
Configuring syb-0.6...
Configuring mtl-2.2.1...
Building syb-0.6...
Building mtl-2.2.1...
Installed syb-0.6
Configuring haskell-src-1.0.2.0...
Installed mtl-2.2.1
Building haskell-src-1.0.2.0...
Installed haskell-src-1.0.2.0
Downloading hs2bf-0.6.2...
Configuring hs2bf-0.6.2...
Building hs2bf-0.6.2...
Failed to install hs2bf-0.6.2
Build log ( /home/builder/.cabal/logs/hs2bf-0.6.2.log ):
cabal: Entering directory '/tmp/cabal-tmp-15791/hs2bf-0.6.2'
Configuring hs2bf-0.6.2...
Building hs2bf-0.6.2...
Preprocessing executable 'hs2bf' for hs2bf-0.6.2...
[ 1 of 10] Compiling Util             ( Util.hs, dist/build/hs2bf/hs2bf-tmp/Util.o )

Util.hs:49:10: error:
    • Overlapping instances for Error [CompileError]
        arising from a use of ‘transformers-0.5.2.0:Control.Monad.Trans.Error.$dmstrMsg’
      Matching instances:
        instance [safe] transformers-0.5.2.0:Control.Monad.Trans.Error.ErrorList
                          a =>
                        Error [a]
          -- Defined in ‘transformers-0.5.2.0:Control.Monad.Trans.Error’
        instance Error [CompileError] -- Defined at Util.hs:49:10
    • In the expression:
        transformers-0.5.2.0:Control.Monad.Trans.Error.$dmstrMsg
          @[CompileError]
      In an equation for ‘strMsg’:
          strMsg
            = transformers-0.5.2.0:Control.Monad.Trans.Error.$dmstrMsg
                @[CompileError]
      In the instance declaration for ‘Error [CompileError]’
cabal: Leaving directory '/tmp/cabal-tmp-15791/hs2bf-0.6.2'
cabal: Error: some packages failed to install:
hs2bf-0.6.2 failed during the building phase. The exception was:
ExitFailure 1