Three minutes
That's how long I'd sit there every time I changed a file on our server. Three to four minutes for the dev server to rebuild and come back up. Long enough to check Slack, scroll twitter, and then forget what I was about to do when it finally came back. I was the only one on Linux. The rest of the team was on Mac, and on their machines the dev server came back in twenty seconds. Nobody else felt the pain, so nobody else was looking for a fix. On my machine it was the bottleneck of my whole day. I started batching changes across multiple files so I'd only pay the rebuild cost once, which sounds clever but mostly meant I'd lose track of what I was actually testing. You don't really notice an hour disappearing into that. You just notice you're tired by 4pm and you can't figure out why.
For a while, I lived with it.
A small experiment
I'd used esbuild in some side projects before. It built things in milliseconds. After enough days of staring at a slow rebuild, I started wondering whether it would work for our server too. I tried it locally first. Wrote a small config, pointed it at our entry files, ran it. The build went from minutes to under a second. I ran the dev server. It came up. Things worked.
