Start: SSR context loss due to dependency externalization

[wobsoriano]

Which project does this relate to?

Start

Describe the bug

Packages installed in node_modules rely on sharing a server context with the main application, such as using AsyncLocalStorage for request-scoped data, auth, or other per-request state. If Vite externalizes these packages during SSR (its default behavior), they may be loaded in a separate context, causing them to lose access to the shared server state.

This can result in runtime errors like:

Error: No HTTPEvent found in AsyncLocalStorage. Make sure you are using the function within the server runtime.
    at getEvent (node_modules/@tanstack/start-server-core/dist/esm/h3.js:30:11)
    ...

Temporary Workaround:

Add the affected package to the ssr.noExternal option in your vite.config.ts file:

export default defineConfig({
  // ...other config
  ssr: {
    noExternal: ['@clerk/tanstack-react-start'],
  },
});

Your Example Website or App

https://codesandbox.io/p/devbox/mdxyzw

Steps to Reproduce the Bug or Issue

1. Create a fresh devinxi based TanStack Start app
2. Install Clerk SDK with devinxi support (npm i @clerk/tanstack-react-start@0.17.0-snapshot.v20250611045520 --save-exact)
3. Run npm run dev
4. Check console

or visit the codesandbox link

Expected behavior

Packages that depend on shared server context should function correctly during SSR, with no loss of context or unexpected errors, even if they are installed in node_modules.

Screenshots or Videos

No response

Platform

• OS: macOS
• Browser: Chrome

Additional context

No response

[solace]

@wobsoriano Out of interest, even with the noExternal, the SignedIn and SignedOut work, but the UserButton, and SignInButton don't render, and SignOutButton renders but does nothing. Is this expected at the moment while this issue is being sorted out?

[solace]

@wobsoriano Out of interest, even with the noExternal, the SignedIn and SignedOut work, but the UserButton, and SignInButton don't render, and SignOutButton renders but does nothing. Is this expected at the moment while this issue is being sorted out?

Started from scratch and added everything back in one at a time. Looks like it was lingui integration based on their tanstack starter that was causing Clerk to fail.

[depsimon]

@solace I just updated the lingui example here, let me know if you have any issues with it