A super simple X11 window manager that centres and full-screens all windows. That's it! No keybindings, no dragging windows.
A simple utility script to start kiosk-wm and run a command.
kiosk-wm-run.sh command
Start kiosk-wm (or exec startx $0 $@ if "$DISPLAY" == "") and execute command.
When command terminates, kiosk-wm will also be terminated.
gcc -lX11 -o kiosk-wm kiosk-wm.c
If you'd like a slightly more sophisticated, but still incredibly simple, window manager to start hacking on, I'd recommend tinywm - that's where I started!