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     base-prelude-1.3
Starting     semigroups-0.19
Building     base-prelude-1.3
Building     semigroups-0.19
Completed    semigroups-0.19
Completed    base-prelude-1.3
Downloading  bytestring-tree-builder-0.2.7.3
Downloaded   bytestring-tree-builder-0.2.7.3
Starting     bytestring-tree-builder-0.2.7.3
Building     bytestring-tree-builder-0.2.7.3
Completed    bytestring-tree-builder-0.2.7.3