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...
cabal: Could not resolve dependencies:
[__0] trying: hwormhole-0.2.0.1 (user goal)
[__1] next goal: saltine (dependency of hwormhole)
[__1] rejecting: saltine-0.1.0.2 (conflict: hwormhole => saltine==0.1.0.1 &&
<1.0)
[__1] rejecting: saltine-0.1.0.1 (conflict: pkg-config package
libsodium>=1.0.13, not found in the pkg-config database)
[__1] rejecting: saltine-0.1.0.0, saltine-0.0.1.0, saltine-0.0.0.6,
saltine-0.0.0.5, saltine-0.0.0.4, saltine-0.0.0.3, saltine-0.0.0.2,
saltine-0.0.0.1 (conflict: hwormhole => saltine==0.1.0.1 && <1.0)
[__1] fail (backjumping, conflict set: hwormhole, saltine)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: hwormhole, saltine