Yesterday, out of nowhere I remembered Zen of Python and looked it up to refresh my memory. Prior to that I hadn't known who the author was, so when I saw Tim Peter's name I had a moment of realization that it's the same person who invented Timsort and the same person who was banned from python forums a few years ago for opposing arguing agains bylaw changes.
It feels surreal to learn about his death just the next day. RIP
Timsort is presumptively the best-known thing, but he did quite a lot else for core CPython development. As far as I can tell, most of it actually relates to algorithms for handling large integers and the Decimal data type.