Simon Willison’s Weblog

29th March 2026

Tool Pretext — Under the Hood — Explore how pure-JavaScript text measurement and line breaking work through an interactive visualization of the Pretext library's pipeline. This tool demonstrates each stage from raw text input through whitespace normalization, word segmentation, canvas-based width measurement, and arithmetic-based line breaking, with live verification against actual DOM rendering.

See my notes on Pretext here.

Posted 29th March 2026 at 7:59 pm

Recent articles

Qwen 3.8 27B on my laptop can interpret model weights, too - 3rd November 2026
The U.S. Census Bureau and “Super Intelligence” - 2nd November 2026
The October inflection point for vibe game development - 28th October 2026
Battle Drones - a vibe coded RTS with audio-based multiplayer - 20th October 2026

This is a beat by Simon Willison, posted on 29th March 2026.

Monthly briefing

Sponsor me for $10/month and get a curated email digest of the month's most important LLM developments.

Pay me to send you less!

Sponsor & subscribe