Just in case, this is my library and I didn't post this to the HN, because I didn't think this is that HN-worthy. Ask me anything anyway.

My main motivation to port libbf was to see if it is faster than usual libraries available in Rust, and yes, some operations are indeed faster than others, but it was tough to compare against Rug which uses MPFR under the hood. I did fully design the library API beforehand and explicitly directed the documentation, testing and benchmark tasks, but of course all the brilliance of the library comes from Fabrice Bellard and not me.