Error when evaluating SSR module - "exports is not defined"

[LeonHeidelbach]

Describe the bug

After upgrading to @sveltejs/kit@2.21.3 I get an exports is not defined error for every route. See logs for further details.

Reproduction

Logs

[vite] (ssr) Error when evaluating SSR module /src/routes/[[loc]]/dashboard/+page.server.ts: exports is not defined
      at eval (eval at runInlinedModule (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/module-runner.js:1062:11), <anonymous>:3:36)
      at ESModulesEvaluator.runInlinedModule (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/module-runner.js:1070:6)
      at SSRCompatModuleRunner.directRequest (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/module-runner.js:1284:82)
      at SSRCompatModuleRunner.directRequest (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/chunks/dep-DBxKXgDP.js:25274:35)
      at SSRCompatModuleRunner.cachedRequest (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/module-runner.js:1179:28)
      at request (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/module-runner.js:1228:79)
      at async eval (eval at runInlinedModule (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/module-runner.js:1062:11), <anonymous>:6:31)
      at async ESModulesEvaluator.runInlinedModule (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/module-runner.js:1062:5)
      at async SSRCompatModuleRunner.directRequest (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/module-runner.js:1284:61)
      at async SSRCompatModuleRunner.directRequest (file:///home/.../node_modules/.pnpm/vite@6.3.5_@types+node@22.15.30_jiti@2.4.2_lightningcss@1.30.1_sass@1.89.1_yaml@2.6.1/node_modules/vite/dist/node/chunks/dep-DBxKXgDP.js:25274:23)

System Info

System:
    OS: Linux 6.14 Arch Linux
    CPU: (24) x64 AMD Ryzen 9 3900X 12-Core Processor
    Memory: 55.60 GB / 62.71 GB
    Container: Yes
    Shell: 5.9 - /usr/bin/zsh
  Binaries:
    Node: 22.12.0 - ~/.volta/tools/image/node/22.12.0/bin/node
    Yarn: 1.22.22 - ~/.volta/bin/yarn
    npm: 10.9.0 - ~/.volta/tools/image/node/22.12.0/bin/npm
    pnpm: 10.11.1 - ~/.volta/bin/pnpm
  npmPackages:
    @sveltejs/adapter-cloudflare: ^7.0.4 => 7.0.4 
    @sveltejs/kit: ^2.21.3 => 2.21.3 
    @sveltejs/vite-plugin-svelte: ^5.1.0 => 5.1.0 
    svelte: ^5.33.18 => 5.33.18 
    vite: ^6.3.5 => 6.3.5

Severity

blocking all usage of SvelteKit

Additional Information

No response

[stayradiated]

I hit the same error and have rolled back to version 2.21.2 for now

[jeannemas]

I also am affected by the issue, so I'm using the 2.21.2 version for now.
I believe the issue was introduced in #13793 .

[teemingc]

Is anyone able to share a minimal reproduction? Or at the very least, the contents/page options of the file reported by the error logs "Error when evaluating SSR module ...", or what command was run npm run dev or npm run preview, or what dependencies were installed, or what SvelteKit or Vite configurations do you have if any, or what inherited options do you have from layouts? I have no idea how to reproduce this at the moment.

[teemingc]

If I google the error message "Error when evaluating SSR module ... exports is not defined", it links to #2418 which happens when a CJS dependency is being bundled and loaded into the Vite Node environment which uses ESM. I'm not sure if this is the same issue since there's not much information to work with here.

Reproduction(?): https://github.com/eltigerchino/kit-13866

[tymonTe]

Same issue here, rollback to 2.21.2 fixed it.
Seems to be related to SentryJS. When I remove it from the server hooks file, all is good.
Supposedly this was addressed here getsentry/sentry-javascript#16124 but the only thing that worked for me is rolling back sveltekit.

VITE v6.3.5  ready in 1959 ms

  ➜  Local:   http://localhost:5173/
  ➜  Network: http://172.20.8.32:5173/
  ➜  Network: http://10.5.0.2:5173/
7:43:24 AM [vite] (ssr) Error when evaluating SSR module /src/routes/(marketplace)/+layout.server.ts: exports is not defined
      at /Users/tymon/PycharmProjects/cloo/app/node_modules/.pnpm/@sentry+sveltekit@9.28.0_@opentelemetry+api@1.9.0_@opentelemetry+context-async-hooks@1._27d67303c488d7a28ac812727662b473/node_modules/@sentry/sveltekit/build/cjs/index.server.js:1:32

[stayradiated]

I'm also using Sentry, so that does seem to be part of the issue. I'll try and put together a minimal reproduction

edit: repro is here

[teemingc]

Reposting here: a fix has been merged in the Sentry SDK and should be out in the next release getsentry/sentry-javascript#16528 (review)

[dualjack]

Got same issue. Almost sh*t myself on production site 😵‍💫
Issue related to Inngest

[bfovez]

Same issue here.

[teemingc]

We will revert the bundling change soon in favour of #13894
In the meantime, if you have a dependency that bundles in CJS code into the server build, you can externalise it by adding it to the vite.config.ts ssr.external setting and it should alleviate this error.