It's basically a drop in replacement for `cabal-install`, while leveraging off Cabal the library, which means package description files don't need to be rewritt

It's basically a drop in replacement for `cabal-install`, while leveraging off Cabal the library, which means package description files don't need to be rewritten, i.e. your old cabal package will still work. It's a huge departure from using cabal-install. Faster project setup time, and not having to worry about managing sandboxes, compiling a new sandbox, or getting stuck in cabal hell. So, yes, you could look at it as a cabal-install rewrite.