AI Coding Tools in Practice: What a 25-40% Productivity Gain Really Looks Like

Our JavaScript team tested AI-assisted development on production code. Here's what we measured, what surprised us, and why we think the real gain is 25-40% -- not the 10x you keep hearing about. Over the past year, AI coding tools have been surrounded by bold claims: "Develop twice as fast." "10x developer productivity." "Code that practically writes itself." We decided to test these claims on real work -- not demo projects, but production code. The kind of long-lived repositories that power SDK