Scripting as Gameplay
Real programming, not just pseudocode. You can use libs from real projects.
Docs and game API of a full-fledged platform.
Programmable Persistent World
Huge persistent world consisting of 40,000 connected game rooms.
30-server cluster (120 CPU cores) processing player scripts using Node.js.
Programmable world living a continuous life 24/7 in real-time even when you're offline.
Open Source Sandbox
Engine released on GitHub as an open and moddable program platform.
You can change any aspect of game objects' behavior.
The sandbox concept doesn't imply any goal or storyline. You just code for fun in a shared game space alongside other players.