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."
At 1:47 AM, Leo replaced his readFileSync with fs.promises.readFile and added await . code with mosh node js
He ran nodemon .
He rewound the video. Mosh was now explaining asynchronous patterns – callbacks, promises, async/await . He didn’t just show the syntax. He explained why each one existed. He showed the mistake. Then he showed the fix. Within seven minutes, Mosh had drawn a diagram
He laughed out loud, waking his cat. Then he kept watching. By 3 AM, he’d learned about middleware, routing, environment variables, and even how to structure a real project with controllers and services. But that’s not your enemy
Leo slammed his laptop shut for the third time that night. His Node.js server was crashing on every POST request, sending back cryptic Cannot read property 'name' of undefined errors. His team’s demo was in 12 hours.
"Okay, Mosh," Leo whispered. "Show me."