bun-plugin-swc

bun-plugin-swc

A Bun plugin for transpiling TypeScript with SWC (Speedy Web Compiler).

Background

As of September 2023, Bun does not support emitDecoratorMetadata, which limits its compatibility with popular libraries such as NestJS. To address this issue, this plugin transpiles TypeScript imports using SWC, then feeds the resulting JavaScript code back into Bun's default JavaScript loader.

Install

bun add --dev bun-plugin-swc

Usage

First, create a preload script to load the plugin:

preload.ts

import { plugin } from 'bun';
import swcPlugin from 'bun-plugin-swc';

void plugin(swcPlugin());

Then, add the preload script to your bunfig.toml:

bunfig.toml

preload = ["./preload.ts"]

[test]
preload = ["./preload.ts"]

For a real world example, see the example project in this repository.