I'm placing this in the GFA BASIC section because the language is actually inspired from it. A while back there was a discussion with the author about backporting X11-BASIC to the ST. Apparently since August this has happened.
I didn't have time to test but from what I read it needs the VT52 emulator running. Not sure if it will work with another emulator but it would be cool to find out. Anyway if someone is willing to test you can download it from the X11-BASIC website.
X11 BASIC is available for Linux, Windows an assortment of other OSes and Android. So it's now possible to do Android development with an Atari! It should be fun!