Dynamic route works on `npm start` but not in web builds about expo HOT 2 CLOSED

In your app.json your web.output is set to static. This means your website is rendered and served as static .html files. If the file doesn't exist, then you will get a 404.

To use dynamic routes with static rendering, you need to tell the bundler what the possible values of [bar] could be. This way it will generate the necessary .html files. https://docs.expo.dev/router/reference/static-rendering/#dynamic-routes

The alternative to static rendering is running your app as a Single Page Application. You can enable this by simply removing output: 'static' from your app.json. Now only a index.html file will be generated. You'll need to run your application via npx serve -s dist (-s enables single page mode) and ensure you setup the correct redirect rules in your deployment.

from expo.

Thank you! The second option (removing output: 'static' and changing to npx serve dist -s) did the trick for our use case.

(Pre-defining the dynamic routes wouldn't work for us because the dynamic route will be for [user].tsx pages, and new users can be created after the build)

from expo.