The first public release of Mini Micro is now available at https://miniscript.org/MiniMicro/!
This runs right in your web browser. After it loads, you should see a welcome message, and a suggestion to type help to get help. From there you can learn about other topics. The complete API is here, but not everything in this API has been implemented yet — in particular, we don't yet have sprites, tiles, or some of the more advanced drawing functions.
Everything else though should be good to go! Please take it for a spin, and leave your feedback here.