Help to find a specific Shmup with tiny file sizes

[robertcook]

Hello,
Many years ago I discovered a very interesting shmup engine, where you control a ship that played a bit like asteroids (that old as hell arcade game), the main thing about this engine is that there's no real fully-developed game on it, but people always submitted their own bosses to be challenged there in a open space, and the sizefile of these "bosses" were almost as big as few Bytes and everything looked as if you're observing things under a microscope, because the sprites were formed by tiny pieces, I never have seen anything that reached a kb long.
it was so long ago that I don't managed to remember it's name neighter be able to find it on internet, do you guys have any idea of what game /engine is that?

[PerishedFraud ឵឵]

Fraxy?