This is one of my favorites so far! I love that you've considered the whole experience, from title-screen to tutorial, game and credits. Music and sounds are great, difficulty feels right, there's humor and the the world feels alive!
I did fall into some bottomless pits that I wished were easier to identify and I wished it was longer, but over all this was a great little game/demo. I hope you expand upon it!
Also best 'credits'-scene I've seen in a long while :) Nice work!