Say Chess | Martin B. Justesen | Substack

Which Opening Offers the Highest ROI to Study?

A new online tool for finding the opening you should fix.

Dec 8, 2025 • Martin B. Justesen

Most Popular

From 1400 to 2000 in Blitz on Chess.com - A 10½ Year Journey

Jul 26, 2022 • Martin B. Justesen

The Botvinnik Method For Chess Improvement

Jun 21, 2023 • Martin B. Justesen

Is the chess (Twitch) boom over?

May 9, 2022 • Martin B. Justesen

I'm Leaving Twitter..

Oct 27, 2024 • Martin B. Justesen

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Recent posts

Vibe Training a Chess Puzzle Model Like Deepmind

Supervised Pre-Training

Nov 8, 2025 • Martin B. Justesen

Building a Systematic Checkmate Pattern Book

Oct 29, 2025 • Martin B. Justesen

I Slept My Way to 2100 in Blitz on Chess.com

It seems fitting to reemerge and give an update on my chess journey now that I have something positive to share.

Aug 6, 2025 • Martin B. Justesen

I Want to Become a Chess Amateur Again

I've decided to close my business, Say Chess Publishing

Mar 29, 2025 • Martin B. Justesen

Newsletter Update: Slow(er) Productivity

In the last 4 years, I have written +300 newsletters and published 19 chess books. It has been a very intense and productive period, but it is also…

Feb 22, 2025 • Martin B. Justesen

Part II of Mapping Checkmate Patterns with a 27-Dimensional Fingerprint

Last week I posted a try to find and organize checkmate patterns using a clustering algorithm combined with a focused look on the 3x3 squares around the…

Feb 13, 2025 • Martin B. Justesen

Mapping Checkmate Patterns with a 27-Dimensional Fingerprint

Some days ago, I read in a blog post on Lichess that the kill box checkmate pattern had been added as a puzzle keyword.

Feb 7, 2025 • Martin B. Justesen

The Tactics Ladder is Now Free

I’ve decided to make TacticsLadder.com completely free to use.

Jan 31, 2025 • Martin B. Justesen

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