Specifying output types to improve TypeScript performance?

[serg06]

Hello! I'm using tRPC 10 with TypeScript 4.9.4. I have a monorepo with a client and a server.

My editor's auto-complete is pretty slow; I'd like to speed it up by explicitly specifying trpc's output types. I know I can use .output() + zod to validate output types at run-time, but I don't need that; I only need to declare the output type.

Is there any way to do that?

[KATT]

You should be able to do it on the callback like on any other callback function. : Promise<Thing>

This issue might be also be solved by splitting up your app more

[serg06]

Ohh wow that works, thank you.

[KATT]

If you split up your backend tRPC router in several packages it should give you a lot of perf gains too, you can do this either by using a monorepo like nx/turbo or by using project references

References:

• https://github.com/microsoft/TypeScript/wiki/Performance
• https://www.typescriptlang.org/docs/handbook/project-references.html

[serg06]

Thanks for the suggestion. We use turbo; I'll start by moving the router to its own package.

I read through project references but don't understand how they could help. They only seem to speed up tsc performance, not editor performance.

[chrisvander]

Editor uses tsc in incremental mode under the hood to parse types. Any improvements to TypeScript compilation will be reflected in editor autocomplete speed.