Resolving dependencies...
Downloading datetime-0.2.1...
Configuring datetime-0.2.1...
Building datetime-0.2.1...
Preprocessing library datetime-0.2.1...

src/Data/DateTime.lhs:13:10:
    Could not find module ‘System.Time’
    There are files missing in the ‘old-time-1.1.0.3’ package,
    try running 'ghc-pkg check'.
    Use -v to see a list of the files searched for.
Failed to install datetime-0.2.1
cabal: Error: some packages failed to install:
activitystreams-aeson-0.2.0.0 depends on datetime-0.2.1 which failed to
install.
datetime-0.2.1 failed during the building phase. The exception was:
ExitFailure 1