@tanstack/react-start RSC build fails in server-fn plugin with Rolldown: `this.resolve` after plugin driver is dropped

[GregoryHouseMD]

Which project does this relate to?

Router

Describe the bug

After upgrading @tanstack/react-start from a known-good lockfile using 1.167.57 to 1.167.63 / 1.167.64, pnpm build fails during the RSC production build.

The failure happens in: [plugin tanstack-start-core::server-fn:rsc]

Rolldown reports: Errored while resolving "zod" in this.resolve. Got Plugin driver is already dropped.

This does not appear to be a missing dependency issue. zod and defu are installed and resolvable. The same app code builds successfully on the older TanStack Start lockfile.

Complete minimal reproducer

https://github.com/GregoryHouseMD/tanstack-start-rsc-plugin-driver-repro

Steps to Reproduce the Bug

1. Clone the minimal reproduction:

   git clone https://github.com/GregoryHouseMD/tanstack-start-rsc-plugin-driver-repro.git
   cd tanstack-start-rsc-plugin-driver-repro
   

2. Install dependencies: pnpm install

3. Build: pnpm build

4. The build fails during [3/5] build rsc environment with:
   [plugin tanstack-start-core::server-fn:rsc] src/server/communityPageInitialData.ts?tss-serverfn-split
   Error: Errored while resolving "zod" in this.resolve. Got Plugin driver is already dropped..

Expected behavior

pnpm build` should complete successfully.

The reproduction uses a documented TanStack Start server function pattern: a top-level Zod schema passed to .inputValidator(...) in a module that exports createServerFn(...), with RSC enabled in vite.config.ts.

Screenshots or Videos

No response

Platform

• Router / Start Version: @tanstack/react-start 1.167.64
• OS: macOS arm64, Darwin 25.3.0
• Browser: N/A, production build failure
• Browser Version: N/A
• Bundler: Vite with Rolldown
• Bundler Version: vite 8.0.10, rolldown 1.0.0-rc.17
• Node: 25.9.0
• Package Manager: pnpm 11.0.0

Additional context

This appears to be a regression.

With the same minimal source files:

• @tanstack/react-start 1.167.64 fails
• @tanstack/react-start 1.167.57 builds successfully

The failure does not appear to be a missing zod dependency. zod is installed and resolvable. The error is thrown while the TanStack Start server-fn RSC plugin is resolving the zod import through this.resolve.

I also tested Vite's Rolldown native plugin settings:

experimental: {
  enableNativePlugin: false,
}

and:

experimental: {
  enableNativePlugin: 'resolver',
}

Both reproduced the same failure.