Resolving dependencies...
Configuring mtl-2.2.1...
Configuring text-1.2.2.1...
Building text-1.2.2.1...
Building mtl-2.2.1...
Installed mtl-2.2.1
Installed text-1.2.2.1
Configuring parsec-3.1.11...
Building parsec-3.1.11...
Installed parsec-3.1.11
Downloading fltkhs-0.5.0.8...
Configuring fltkhs-0.5.0.8...
Failed to install fltkhs-0.5.0.8
Build log ( /home/builder/.cabal/logs/fltkhs-0.5.0.8.log ):
cabal: Entering directory '/tmp/cabal-tmp-27240/fltkhs-0.5.0.8'
cabal: Leaving directory '/tmp/cabal-tmp-27240/fltkhs-0.5.0.8'
cabal: Error: some packages failed to install:
fltkhs-0.5.0.8 failed during the configure step. The exception was:
user error ('/opt/ghc/8.0.2/bin/ghc' exited with an error:

/tmp/cabal-tmp-27240/fltkhs-0.5.0.8/dist/setup/setup.hs:28:1: error:
Failed to load interface for ‘System.Directory’
It is a member of the hidden package ‘directory-1.2.6.2’.
Perhaps you need to add ‘directory’ to the build-depends in your .cabal file.
Use -v to see a list of the files searched for.

/tmp/cabal-tmp-27240/fltkhs-0.5.0.8/dist/setup/setup.hs:29:1: error:
Failed to load interface for ‘System.FilePath’
It is a member of the hidden package ‘filepath-1.4.1.0’.
Perhaps you need to add ‘filepath’ to the build-depends in your .cabal file.
Use -v to see a list of the files searched for.
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