Facebook Engineering Blog
The Death of Traditional Testing: Agentic Development Broke a 50-Year-Old Field, JiTTesting Can Revive It

The Death of Traditional Testing: Agentic Development Broke a 50-Year-Old Field, JiTTesting Can Revive It

2/11/2026 · Mark Harman

What this post added

This post introduces Just-in-Time Tests (JiTTests) as a novel approach to software testing, leveraging LLMs to automatically generate tests on-the-fly for specific code changes. It highlights how JiTTests address the limitations of traditional testing in the context of agentic development by eliminating maintenance overhead, reducing false positives, and focusing on catching critical bugs just before production.

Read the original post ↗