Of course it's a joke.

I will still be using Pyxel to program the game, but now that I can package the game in one single .exe file you will no longer have to install Pyxel in order to play the game.

The soft I'm using is called Nuitka. It's an intelligent program that fully packages a python file in one .exe file. 

Still, Kitao, the Pyxel developer, is planning on making a complete standalone version for Pyxel and I will probably use it.