Runtime Requirements

oRPC is built on ES2022 and a small set of standard Web APIs. This page lists exactly what it needs and the minimum versions that provide it on Node.js, Deno, Bun, Cloudflare Workers, browsers, Android, and iOS.

oRPC’s core abstractions are written against the JavaScript language and standard Web APIs. Runtime-specific integrations live in adapters and runtime packages. If a runtime provides the features required by the packages and features you use, oRPC runs on it.

Overview

Browsers update themselves, so there is nothing to recommend beyond the minimum. Edge and Chrome on Android match Chrome, Samsung Internet needs 17.0, and Safari on iOS matches iOS WebView. Cloudflare Workers tracks current V8 and ships every Web API oRPC uses; use the Fetch Adapter there. React Native is not a web view and needs a polyfill.

Some optional features need more: compression needs Deno 1.19, Bun 1.3.3, and Firefox 113; AsyncIteratorObject needs Firefox 105 and Bun 1.1.23; Blob or File payloads need Node.js 20; and the Encryption, Signing, and Pino integrations need Node.js 19 for a bare crypto global.

Language Level

oRPC is written and type-checked against ES2022, and the published bundles are not compiled down any further.

Available from Node 16.11 · Deno 1.14 · Bun 1.0 · Chrome 94 · Firefox 93 · Safari 16.4 · Android WebView 94 · iOS WebView 16.4.

Web APIs

Beyond ES2022, oRPC uses the APIs below. Every one is Baseline Widely available, meaning it landed in every major browser at least 30 months ago. The dates are when that happened.

Version numbers come from MDN’s browser compatibility data. A few rows need more explanation:

• TransformStream must exist before you import oRPC. oRPC declares its AsyncIteratorObject decoder as a class that extends TransformStream at module scope, so a runtime without it fails on import '@orpc/client' with ReferenceError: TransformStream is not defined, before any of your code runs. This is what sets the Firefox minimum at 102.
• Response is not only for the Fetch adapter. It is the standard way to read and write multipart bodies, so oRPC uses new Response(form) to encode FormData and .formData() to decode it. That makes Response a requirement for the Node.js, Fastify, AWS Lambda, WebSocket, and Message Port adapters too, even though none of them speak the Fetch API. Request is not part of that path. The AWS Lambda adapter also needs Node’s Buffer.
• A plain Blob is enough to require File. oRPC reads File.name to build the Content-Disposition header, and builds a File when parsing an upload. ReadableStream payloads do not need it.
• Blob, File, URL, and FormData are handled the same way by the RPC Serializer and the OpenAPI Serializer.

React Native

React Native does not run in a web view. It runs JavaScript in Hermes, which does not provide the browser APIs above, so the WebView numbers do not apply to it.

Three things need attention:

• Web Streams are missing. Hermes has no TransformStream, so importing oRPC throws ReferenceError: TransformStream is not defined before any of your code runs. Expo has installed ReadableStream, WritableStream, and TransformStream as native globals since SDK 53, which fixes it. On bare React Native, add a Web Streams polyfill that provides TransformStream, and load it from your entry file before importing oRPC.
• React Native 0.78 is the floor, and it is a syntax limit. oRPC uses a class static initialization block. Metro has no transform for it, and Hermes could not parse one until React Native 0.78, so anything older fails to load and no polyfill can help. Every Expo SDK from 53 up is past that line. The ES2022 builtins are not the problem: Hermes has had Object.hasOwn, the Error cause option, and .at() since React Native 0.71, even though it still documents itself as ES6 plus selected later additions.
• Some globals are missing entirely. There is no crypto global on native at any Expo SDK, and React Native’s Blob lacks arrayBuffer(), text(), and stream(), which is why binary payloads have to travel as ArrayBuffer rather than blobs.

After startup, React Native’s built-in fetch still does not support streaming, which limits binary data and AsyncIteratorObject rather than oRPC itself. Expo fixes the first two: it provides the Web Streams globals and, from SDK 56, installs the streaming expo/fetch as the global fetch. The missing crypto global and the incomplete Blob remain. See the Expo Adapter for setup.