The easiest way to achieve typesafe APIs in SvelteKit. This is meant to be an easy, simple and lightweight alternative to tRPC-SvelteKit. Kavi handles both +page.server.ts, +page.ts and +page.svelte files seamlessly.

npm i kavi zod

// server
export const router = {
  add: middleware.args(z.tuple([z.number(), z.number()])).call(([a, b]) => {
    return a + b
  }),
}

// client
await api.add([1, 2]).ok() // 3

Read more in the docs