I've been having a lot of fun with https://kalumajs.org/ recently for silly JS embedded things. It's been great so far, and has a cool little community!
It's a runtime built on top of JerryScript, which has been pretty neat to look into as well: https://jerryscript.net/
It's a runtime built on top of JerryScript, which has been pretty neat to look into as well: https://jerryscript.net/