Migrating from v1

v2 is a complete rewrite of webserial-core and is not backwards compatible with v1.

Version 2 introduces a new architecture, new adapter system, new folder structure, new build output format, and changes to every public API. There is no incremental upgrade path.

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Recommended approach

The cleanest way to migrate is to start fresh with v2:

1. Uninstall v1 and install v2:

   npm remove webserial-core
   npm install webserial-core@latest

2. Delete any existing extension of the old SerialDevice class.

3. Create a new class extending AbstractSerialDevice<T> following the Getting started guide.

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Why a full rewrite?

Version 1 was a prototype that proved the concept. Version 2 was designed from scratch with the following goals that required breaking changes at every layer:

• Strict TypeScript — no any, full JSDoc, named interfaces for every option
• Modular adapter system — WebUSB, Web Bluetooth, and WebSocket are first-class transports
• Dual ESM + CJS output — proper .mjs / .cjs / .umd.cjs build via Vite
• Isolated responsibilities — parsers, queue, events, registry, and adapters are all separate modules that can be tested independently
• English-only source — all source code, JSDoc, and error messages are in English

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Reference

Start here

Read the Getting started guide for the full v2 API.

• API — AbstractSerialDevice
• API — Events
• API — Parsers
• Examples