BOTW: 2020.02.07

The latest and greatest free chess engines, Magnus aces an endgame test, and an online bullet match between two Canadian women's Olympiad teammates are this week's Best of the Web...


Stockfish 11

For years, Stockfish has been the strongest publicly-available chess engine, and it remains the strongest CPU chess engine. Version 11 was released January 18, 2020, and can be downloaded here.

Open-source, and constantly updated by contributors from around the world, Stockfish continues to improve, with 18 functional changes since version 11. If you want the absolutely most up-to-date version, download from the development version page.

Make sure you get the right version, as Stockfish is available for Windows, Android, Linux, and Mac.

Note: recent intel CPUs run best on the Haswell builds, while AMDs run faster on the "modern computers" builds. 

 Leela Chess Zero

Originally an attempt to replicate the stunning play of Google Deep Mind's AlphaZero program, Leela is now the strongest chess engine available, consistenly beating all versions of Stockfish in 1 vs 1 events. With millions of self-play games contributing to its latest nets, Leela continues to improve. Like Stockfish, Leela is also open-source and freeware, and a top-notch analyst. However, just like AlphaZero, Leela is a neural-net engine, and requires highly parallelized processing that only GPUs can provide, with an Nvidia GTX at a minimum and an Nvidia RTX being by far the fastest. 

The Lc0 website has recently been updated, and includes a wider variety of links and more user-friendly introductions to help choose and set up the version of Leela for your likes and hardware.


  • because Leela requires a CUDA-supporting GPU to function even close to its potential, there are no versions of it for Mac or Android.
  • Lc0 is an attempt to duplicate the "zero human knowledge" input of AlphaZero. It has succeeded at this, but has not exactly duplicated some of AlphaZero's most outstanding moves. Because of Lc0's success, and some of its very idiosyncratic failures -- such as "trolling" opponents by sacrificing pieces in endgames when it could play shorter forced mates -- the Lc0 project has splintered into many not-quite-zero alternatives, such as "Leelenstein" and "Bad Gyal" and "Fat Fritz", each of which attempts to combine Leela with the developer's own ideas, with varying degrees of success. You can find links to some of those versions from the Lc0 website, and you can follow online competitions between the top engines and their variants here


Magnus Aces Endgame Test

Last year, Magnus Carlsen bought chess24 and entered a business deal with Chessable, the online "spaced repetition" chess learning site. To promote the Chessable version of "100 Endgames You Must Know" -- the well-reviewed 2016 New in Chess book by GM Jesus de la Villa -- Magnus took the course's 26-question intro test and explained his answers to IM John Bartholomew in a 31 min video, which you can watch here.  

Magnus was nearly perfect at the test -- of course -- but that's hardly the reason to watch the video. You can enjoy this as both an endgame refresher -- hit the pause button before MC starts to talk aloud through his answers -- or just as a chance to hear the world's best player explain his thinking. 

You might notice how often Magnus choose an "alternative" solution to the one accepted in the Chessable course -- an annoying but common problem in Chessable for anyone (like me) who thinks that knowing/finding one winning continuation is enough in these technical positions. Second, notice how often Magnus doesn't know the names of the principles or maneuvers that IM Bartholomew and the Chessable course use. The point here is not that Magnus or Chessable is right or wrong -- finding the right moves is the most important thing, and they both get this right -- but it shows that the world's best player thinks about endgames in a way that is different from the way one of the world's most successful endgame books teaches them. 


Botez vs Zhou -- Bullet (Re)match

Saturday, February 8, 2020. 6:30pm EST.

WFM Alexandra Botez has become a full-time twitch streamer since moving to NYC last year. Recently, she introduced matches against other female players, most recently against WFM Anna Cramling. This weekend, Alex plays a first-to-ten online bullet match against Canadian Olympiad teammate FM Qiyu Zhou. Commentary by NM John Williams.

This is an accelerated rematch, after Qiyu won their 3+0 match 10-0 (!!) in December. Despite that earlier result, Alex is the favourite at a 1m + 0s time control: not only does she play it regularly, but Qiyu cannot be in top form as she prepares for her U of T midterms.

Note: Alexandra now streams with her sister Andrea on a new twitch stream name and link:

photo: commentator GM Aman Hambleton and Qiyu Zhou react to Alexandra haning a piece in their match. QZ took it and won, en route to a 10-0 adoption.