Whats an easy way to catch github webhook to execute a shellscript?

I have a programm running on my ubuntu server that I want to automaticly update itself upon a push on master.
I know I could just setup an apache webserver for this, but that seams total overkill.
So is there a tool that simply waits for a webhook to come in and then trigger a shellscript?
I've looked online but there doesn't seam to be anything mature enough.