ENABLE_DEV_WARNINGS is true in production since v7.0.2 due to always-resolving development build

[onozaty]

Reproduction

You can reproduce this issue using the following environment:

• https://stackblitz.com/edit/github-fpqca3jn

Steps:

1. Open the StackBlitz project
2. Run the following commands in the terminal:

   npm run build && npm run start
   

3. Visit a non-existent URL, such as /abc
4. You will see the following development-only warning in the console:

GET / 200 - - 57.135 ms
Error: No route matches URL "/abc"
    at getInternalRouterError (file:///home/projects/github-fpqca3jn/node_modules/react-router/dist/development/chunk-C37GKA54.mjs:4731:5)
    at Object.query (file:///home/projects/github-fpqca3jn/node_modules/react-router/dist/development/chunk-C37GKA54.mjs:2892:19)
    at handleDocumentRequest (file:///home/projects/github-fpqca3jn/node_modules/react-router/dist/development/chunk-KIUJAIYX.mjs:1344:40)
    at requestHandler (file:///home/projects/github-fpqca3jn/node_modules/react-router/dist/development/chunk-KIUJAIYX.mjs:1259:24)
No routes matched location "/abc"
GET /abc 404 - - 20.615 ms

System Info

System:
    OS: Linux 5.0 undefined
    CPU: (8) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
    Memory: 0 Bytes / 0 Bytes
    Shell: 1.0 - /bin/jsh
  Binaries:
    Node: 20.19.1 - /usr/local/bin/node
    Yarn: 1.22.19 - /usr/local/bin/yarn
    npm: 10.8.2 - /usr/local/bin/npm
    pnpm: 8.15.6 - /usr/local/bin/pnpm
  npmPackages:
    @react-router/dev: ^7.7.1 => 7.7.1 
    @react-router/node: ^7.7.1 => 7.7.1 
    @react-router/serve: ^7.7.1 => 7.7.1 
    react-router: ^7.7.1 => 7.7.1 
    vite: ^6.3.3 => 6.3.5

Used Package Manager

npm

Expected Behavior

When running in a production environment (NODE_ENV=production), development-only warnings like No routes matched location should not be shown.
The internal flag ENABLE_DEV_WARNINGS should be false, and the production build (dist/production) should be used.

Actual Behavior

Even with a production build and NODE_ENV=production, accessing a route that does not exist (e.g. /abc) prints the following development warning:

No routes matched location "/abc"

This is caused by dist/development being resolved instead of dist/production, which sets:

• ENABLE_DEV_WARNINGS = true

As a result, development-only logs are shown in production.

Additional Context

This issue appears to have been introduced in PR #12437, which modified the exports field in package.json to always point to the development build for Node.js environments:

[michaelsavchuk]

Oh, good find. I was just dealing with this today too, thanks for all the extra context around why this is happening!

[kasperrt]

We also get this in all builds, regardless of how we force our builds into production

[medanat]

Not ideal, but was able to get around it by aliasing the imports in my production vite config to point to the production dist:

      resolve: {
        alias: {
          ...
          'react-router/dom': '/node_modules/react-router/dist/production/dom-export',
          'react-router': '/node_modules/react-router/dist/production/index'
        }
      }

It stopped the development console.logs from showing up, and shaved 1713 bytes off the final bundle.

YMMV