Mmmh yeah, forgot to answer the original question !

wmutils' goal is to provide a simple, standalone and scriptable interface to the X server. Think coreutils, but for X. It grew from the fact that EWMH is a pain to work with, and that you shouldn't need a fully-fledged WM when all you need is moving the current window 10 pixels to the right.

Its composability make it very well suited to control windows from a key binder like xbindkeys or sxhkd.

Over the years, I realize that if you need to react to X events (window creation, deletion, ...) you need an piece of software monitoring those events, and triggering changes. That is why I made my own WM whose only purpose is to provide resizing and moving with the mouse. I made it as a first class citizen for wmutils, so everything I do with the keyboard is done with wmutils.