Hardware random number generators are tricky. This project doesn't appear to have mentioned any of the tricky parts or how they were tackled. It looks like a fun project to noodle about with though!

Spotting correlation and skew is interesting. Finding the right balance of speed and fidelity is tricky.

Here's some previous comment about Entropykey (https://news.ycombinator.com/item?id=1453299) and here's some stuff about testing and using hardware RNGs that I was reading a while ago (https://news.ycombinator.com/item?id=6060636)