Native Bun production build support for TanStack Router

[RentnerKev]

Hi!

I've been exploring native Bun bundler support for TanStack Router as an optional alternative to the existing bundler integrations.

I have a small working implementation of @tanstack/router-plugin/bun that reuses the existing route generator and code-splitting compiler.

The implementation currently supports production builds, lazy route chunks, shared modules, and concurrent builds. Existing Vite, Rsbuild, Webpack, and esbuild integrations remain unchanged.

The initial changes are approximately 105 net lines of production TypeScript, plus tests, CI, and package configuration.

One known limitation is Bun's handling of original input source maps. This is covered by an explicit expected-failure test.

Before submitting a PR, I'd like to confirm whether the maintainers would welcome this as an optional Router integration and whether the known source-map limitation is acceptable for an initial contribution.

Would this be a suitable scope for an upstream PR?

[schiller-manuel]

what's the exact issue with source maps? is there an existing bun issue for this?

in general, yes this would be nice to have. i looked into this some time ago but didn't pursue it as the watchChange hook wasnt supported in unplugin/bun: https://unplugin.unjs.io/guide/#supported-hooks

how did you get around that?