The deploy fails because the code uses a package that isn't in package.json. It worked on your computer because the package happened to be installed there.
What you see
The build fails with Cannot find module 'something' or Could not resolve "some-package", for a package the code imports by name.
Why it happens
The package is installed on your computer (by hand, or by another project) but isn't listed in package.json, so the build server, which installs only what package.json lists, never gets it.
How to fix it
- Run
npm install <package>in the project, so it's added topackage.json. - Commit
package.jsonand the lockfile together, then push.
Or ask your AI tool to fix it
Paste this into Lovable, Bolt, v0, Replit or Cursor:
My app fails to build when deployed because a package it imports isn't installed. Add every package the code imports to package.json (and the lockfile), with the versions the code expects.
The full page, with the request ready to copy, is at launchpad.axonscape.com/fix/module-not-found-package-not-installed. I work on Launchpad by Axonscape, which runs a free launch check for apps built with AI tools: it finds this and the other things that break at launch, from a public GitHub repo or a .zip of the code, and keeps nothing.
Top comments (1)
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