∇ Guide

AI 101 is becoming ∇ Guide and moving to the end of the week. We’re going beyond the basics of AI concepts, models, and techniques, connecting these explanations to our Almanac. The symbol is called nabla, used in math to express a gradient. A small nod to how models learn, as we keep learning ourselves.

AI 101

∇ Guide: Test-Time Training – A Model That Changes While You Use It

17 min read

Sep 12, 2026

∇ Guide: Test-Time Training – A Model That Changes While You Use It

How models can keep learning during inference – and why test-time training could be a key to overcome the limitations of agents and world models.

Alyona Vert.

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