ssr: false: build script creates a server bundle and deletes it

[Hawmex]

I'm using React Router as a...

framework

Reproduction

Prior to v7, we used v6 and component routes. After upgrading to v7 as a framework and setting ssr: false, we faced some problems including:

• @mui/icons-material imports started to fail. So we added this to vite.config.ts:

  ...
  resolve: {
    alias: {
      '@mui/icons-material': '@mui/icons-material/esm'
    }
  }
  ...
  

• the build script started to fail. The client bundle would be created with no errors. However, the build script would try to create a server bundle and face import resolution errors with @mui/utils (this is used in @mui packages' internals).
  We currently have solved this issue by using the current vite.config.ts:

  ...
  ssr: {
    noExternal: command === 'build' ? true : [],
  }
  ...
  

  The interesting thing is that with the current setting, the server bundle will be created successfully and then it gets deleted. What is the reason to this?
• We also have problems using client side components in ErrorBoundary when facing 404 error. It complains about the unavailability of browser globals such as local storage. I had assumed that upgrading to v7 and using the SPA mode would be seamless. I have set SSR to false and yet I am facing problems here and there regarding SSR in the prod and dev environments.

System Info

System:
    OS: Windows 11 10.0.26100
    CPU: (6) x64 Intel(R) Core(TM) i5-8400 CPU @ 2.80GHz
    Memory: 5.96 GB / 15.78 GB
  Binaries:
    Node: 22.12.0 - C:\Program Files\nodejs\node.EXE
    npm: 10.8.1 - C:\Program Files\nodejs\npm.CMD
    pnpm: 9.15.0 - ~\AppData\Roaming\npm\pnpm.CMD
  Browsers:
    Edge: Chromium (131.0.2903.86)
    Internet Explorer: 11.0.26100.1882
  npmPackages:
    @react-router/dev: ^7.0.2 => 7.0.2
    @react-router/fs-routes: ^7.0.2 => 7.0.2
    @react-router/node: ^7.0.2 => 7.0.2
    @react-router/serve: ^7.0.2 => 7.0.2
    react-router: ^7.0.2 => 7.0.2
    vite: ^5.4.11 => 5.4.11

Used Package Manager

pnpm

Expected Behavior

Having a complete client-side router that gives us the option of using file-based routing, in case ssr: false.

Actual Behavior

Server bundle generation during build, and import resolution errors that didn't exist with v6.

[khatabakhsh]

I have this issue, too!

[pfe-nazaries]

Im facing something similar with rxjs and ant design where the SSR build (sometimes in dev mode too) cannot find some modules

[vite] Internal server error: Cannot find module '/Users/pfe/WebstormProjects/rtr-admin/node_modules/.pnpm/[email protected][email protected][email protected][email protected][email protected][email protected]/node_modules/rc-util/es/omit' imported from /Users/pfe/WebstormProjects/rtr-admin/node_modules/.pnpm/[email protected][email protected][email protected][email protected][email protected][email protected]/node_modules/antd/es/layout/layout.js
[VITE] Did you mean to import "rc-util/es/omit.js"?

And i not using ssr at all, just spa mode (ssr:false)