Leo froze. He looked back at his code. He was using fs.readFileSync inside his route handler. Sync. Inside a loop.
The first video that popped up was titled "Node.js Tutorial for Beginners" – but the thumbnail showed a calm, bearded man in a gray t-shirt. No flashy arrows. No shocked faces. Just a whiteboard. code with mosh node js
He ran nodemon .
At 1:47 AM, Leo replaced his readFileSync with fs.promises.readFile and added await . Leo froze
Within seven minutes, Mosh had drawn a diagram of the event loop on a virtual whiteboard. His voice was steady, almost meditative. "Node is single-threaded, Leo. But that’s not your enemy. Your enemy is blocking the event loop with synchronous code." almost meditative. "Node is single-threaded