Hammerspoon
www.hammerspoon.org
What Jamie wrote
I’m a big fan of automation, and I've long wanted to learn Lua.
This is a tool for powerful automation of OS X. At its core, Hammerspoon is just a bridge between the operating system and a Lua scripting engine. What gives Hammerspoon its power is a set of extensions that expose specific pieces of system functionality, to the user.
This might be interesting.