Troubleshooting

"Could not start the interactive dashboard" / a React-related error on dev

This happens when nextdoctor is installed as a per-project dependency (npm install --save-dev) inside a project that already has a differentmajor React version installed — e.g. any Next.js 15+/16+ project, which ships React 19. npm can hoist the dashboard's UI library onto the host project's React instead of nextdoctor's own, and the two aren't binary-compatible. diagnose and fix are unaffected either way.

If you hit this on `dev`, run it via npx or a global install instead:

Neither shares a node_modulestree with the target project, so there's nothing to collide with. Since 0.1.1, this degrades to plain-text output with a clear message instead of crashing.

Which install method should I use?

• diagnose / fix— any install method works fine; they never touch the dashboard's dependencies.
• dev — prefer npxor a global install. Per-project install works too as long as it doesn't collide with a different React major version in that project.