I prefer JavaScript personally, but it’s time to acknowledge that TypeScript has won. If you want to contribute and succeed as a developer in the JS ecosystem, you need to learn TS, like it or not.

That actually is directly addressed on that website https://github.com/MKorostoff/1-pixel-wealth/blob/master/THE_PAPER_BILLIONAIRE.md

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There are a bunch of other languages and countries here https://github.com/MKorostoff/1-pixel-wealth/blob/master/README.md