router-core: ssr/types.d.ts references stripped @internal field, breaks tsc for consumers typechecking libs

[oddsund]

Which project does this relate to?

Router

Describe the bug

packages/router-core/src/ssr/types.ts declares:

export interface DehydratedMatch {
  i: MakeRouteMatch['id']
  b?: MakeRouteMatch['__beforeLoadContext']
  ...
}

RouteMatch['__beforeLoadContext'] is tagged @internal. Since #4907 ("refactor(router-core): strip internal types from public build", 2025-08-10) enabled stripInternal repo-wide, that field has been removed from the published .d.ts — but this indexed-access reference to it was never updated, so it's been a dangling reference in every published .d.ts since router-core@1.171.16 (2026-08-04). #6118 later moved the interface to its current file unchanged, carrying the bug forward.

It went unnoticed by plain SPA consumers because nothing in the always-imported client path pulled ssr/types.ts into their type graph — until #7805's load-client.ts rewrite (also 2026-08-04) started importing TsrSsrGlobal from ./ssr/types.

Complete minimal reproducer

https://stackblitz.com/edit/tanstack-tsc-bug-rlvy22xm

Steps to Reproduce the Bug

npm install && npx tsc in the example repo

Observe that tsc fails on router-core's own shipped types:

node_modules/@tanstack/router-core/dist/esm/ssr/types.d.ts(5,24):
error TS2339: Property '__beforeLoadContext' does not exist on type 'MakeRouteMatch'.

Expected behavior

tsc passes against a stock createRouter/createRootRoute setup with default compiler options.

Screenshots or Videos

No response

Platform

• @tanstack/react-router: 1.170.32 (latest as of writing; bug present since 1.170.19 / router-core 1.171.16, 2026-08-04)
• @tanstack/router-core: 1.171.27 (latest as of writing; broken since 1.171.16)
• TypeScript: 7.0.2

Additional context

No response

[Sheraff]

Out of curiosity, why do you typecheck your dependencies?

[oddsund]

Mostly for completeness and correctness, I guess.
Someone who has thought more about this than me(the people creating Typescript) has set the skipLibCheck to false as a default, so I haven given it that much thought to be honest. 😅

Oh, and I probably should have mentioned this; I created the PR #8206 to fix it by inlining the type of RouteMatch['__beforeLoadContext']. Didn't think about the @internal annotation as a fix, but I thought about removing the field(which would be the same as @internal for external consumers?). I eventually decided against it to avoid breaking it for any consumers who is using it. But maybe this is internal stuff that consumers shouldn't be poking around anyways?