I tried to write a raycast [1] in JavaScript once, I used lines instead of the traditional grid, but it end up messy and with weird texture artifacts. Still, I would like one day to come back to this and do a proper job.

I'll download the game after work and see if I can run it under an emulator, but the graphics and music alone seems wonderful.

1 - https://github.com/victorqribeiro/myRaycast