Warning: The install command is a part of the legacy v1 style of cabal usage.

Please switch to using either the new project style and the new-install
command or the legacy v1-install alias as new-style projects will become the
default in the next version of cabal-install. Please file a bug if you cannot
replicate a working v1- use case with the new-style commands.

For more information, see: https://wiki.haskell.org/Cabal/NewBuild

Resolving dependencies...
Starting     StateVar-1.1.1.1
Starting     hashable-1.3.0.0
Building     StateVar-1.1.1.1
Building     hashable-1.3.0.0
Completed    StateVar-1.1.1.1
Starting     contravariant-1.5.1
Building     contravariant-1.5.1
Completed    hashable-1.3.0.0
Starting     unordered-containers-0.2.10.0
Building     unordered-containers-0.2.10.0
Completed    contravariant-1.5.1
Completed    unordered-containers-0.2.10.0
Starting     intern-0.9.2
Building     intern-0.9.2
Completed    intern-0.9.2
Downloading  libffi-dynamic-0.0.0.2
Downloaded   libffi-dynamic-0.0.0.2
Starting     libffi-dynamic-0.0.0.2
Building     libffi-dynamic-0.0.0.2
Completed    libffi-dynamic-0.0.0.2