Resolving dependencies...
Starting     hcom-0.0.0.3
Building     hcom-0.0.0.3
Failed to install hcom-0.0.0.3
Build log ( /home/builder/.cabal/logs/ghc-8.10.2/hcom-0.0.0.3-14KtMphHyu367VAGdpPMv4.log ):
cabal: Entering directory '/tmp/cabal-tmp-20730/hcom-0.0.0.3'
Configuring hcom-0.0.0.3...
Warning: Packages using 'cabal-version: >= 1.10' must specify the
'default-language' field for each component (e.g. Haskell98 or Haskell2010).
If a component uses different languages in different modules then list the
other ones in the 'other-languages' field.
Building hcom-0.0.0.3...
Warning: No documentation was generated as this package does not contain a
library. Perhaps you want to use the --executables, --tests, --benchmarks or
--foreign-libraries flags.
cabal: No executables and no library found. Nothing to do.

cabal: Leaving directory '/tmp/cabal-tmp-20730/hcom-0.0.0.3'
cabal: Error: some packages failed to install:
hcom-0.0.0.3-14KtMphHyu367VAGdpPMv4 failed during the final install step. The
exception was:
ExitFailure 1