Byte-Sized Design

Byte-Sized Design

Meta Used LLMs to Build Tests That Are Supposed to Fail

The tests that were built to fail

Byte-Sized Design's avatar
Byte-Sized Design
Feb 24, 2026
∙ Paid

TLDR

Most test generation tries to make tests pass. Meta built a system where the whole point is to make them fail, on the code change you’re about to land, before it lands. Out of 41 engineer reach-o…

User's avatar

Continue reading this post for free, courtesy of Byte-Sized Design.

Or purchase a paid subscription.
© 2026 Byte-Sized Design · Privacy ∙ Terms ∙ Collection notice
Start your SubstackGet the app
Substack is the home for great culture