Games can be some very large complex projects. Did you guys write it in javascript or some other language and compile to js? If you guys did just write in js

Games can be some very large complex projects. Did you guys write it in javascript or some other language and compile to js? If you guys did just write in js did you use any other tooling for features like modules? The game looks cool, and I'm thinking about buying it. It's nice to show that electron is a viable platform for games, because you easily gain cross platform compatibility with linux / mac.