Resolving dependencies...
Downloading AVar-0.0.1...
Configuring AVar-0.0.1...
Building AVar-0.0.1...
Failed to install AVar-0.0.1
Build log ( /home/builder/.cabal/logs/AVar-0.0.1.log ):
cabal: Entering directory '/tmp/cabal-tmp-8794/AVar-0.0.1'
Configuring AVar-0.0.1...
Building AVar-0.0.1...
Preprocessing library AVar-0.0.1...
[1 of 1] Compiling Data.AVar        ( Data/AVar.hs, dist/build/Data/AVar.o )

Data/AVar.hs:27:1: error:
    Failed to load interface for ‘System’
    Use -v to see a list of the files searched for.
cabal: Leaving directory '/tmp/cabal-tmp-8794/AVar-0.0.1'
cabal: Error: some packages failed to install:
AVar-0.0.1 failed during the building phase. The exception was:
ExitFailure 1