The author mentions XMonad, which does precisely that. However, you can update XMonad without "restarting" the program. When you update the config, which is jus

The author mentions XMonad, which does precisely that. However, you can update XMonad without "restarting" the program. When you update the config, which is just a haskell program - the config is recompiled and launched. The state of your current session is then passed over to the new config process, and the old one config process is discarded.