Not sure you are aware, but there is an opensource version.
I did some updates on my fork: https://github.com/xesf/jc_reborn
There's also on older attempted to make it using JS: https://github.com/xesf/castaway
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Yes, I'm aware, my Go port is based off of the original port by Jérémie GUILLAUME: https://github.com/jno6809/jc_reborn