Comment by mrl5

Interesting fact that under the hood it's based on tANS introduced by Jarosław Duda from Jagiellonian University:

some cool references:

https://www.youtube.com/watch?v=uXtmN9fE01k

https://th.if.uj.edu.pl/~dudaj/

https://demonstrations.wolfram.com/DataCompressionUsingAsymm...

https://encode.su/threads/2078-List-of-Asymmetric-Numeral-Sy...