@ez-rpc/client

A typed fetch client that derives its types directly from your Zod schemas — no codegen, no manual interface definitions. Pass it the same endpoint map you gave createRouter on the server, and every method on the returned client is fully typed: correct argument types, correct return type, red squiggles if something's wrong.

Works in the browser, Next.js (both client and server components), and any environment with fetch.

Install

npm install @ez-rpc/client zod

Usage

import { createApiClient } from "@ez-rpc/client";
import { userEndpoints } from "../../contract/user";

export const userApi = createApiClient(userEndpoints, "/user", {
  baseUrl: process.env.NEXT_PUBLIC_API_URL,
  appSecret: process.env.NEXT_PUBLIC_APP_SECRET, // optional — enables HMAC signing
});

const { data: users } = await userApi.getUsers();
const { data: newUser } = await userApi.createUser({ name: "Alice", email: "[email protected]" });

The argument type of createUser is inferred from the input schema in your contract. The type of data is inferred from the output schema. Change either one on the server and TypeScript will tell you immediately on the client.

Every response is an ApiResponse<T>:

type ApiResponse<T> =
  | { success: true;  status: number; data: T }
  | { success: false; status: number; error: string }

Other features

• In-flight deduplication — identical concurrent calls share one request instead of hitting the server multiple times
• Retry with exponential backoff — 1 retry by default, configurable
• 5-minute timeout by default
• HMAC-SHA-256 signing — when appSecret is set, every request is signed and the server middleware verifies it
• NDJSON streaming — for streaming endpoints, pass onProgress to receive rows as they arrive:

const { data: rows } = await reportApi.streamReport(input, {
  onProgress: (count) => setRowCount(count),
});

Full docs

See the ez-rpc README.