1. https://www.neonious.com/lowjs/ (https://www.neonious.com/lowjs/)
2. https://github.com/cesanta/elk (https://github.com/cesanta/elk)
3. http://www.espruino.com/ (http://www.espruino.com/) (interesting: for the thingy52 (http://www.espruino.com/binaries/travis/master/))
4. https://jerryscript.net/ (https://jerryscript.net/)
5. https://tessel.io/ (https://tessel.io/)
I have some fairly good research skills, if anyone wants to point me in a certain direction I can probably be useful (or a pain :smiley-confuse: ).
I am converting to Arduino an entire High School Robotics course that I have designed and student tested for several years.