Today I would like to introduce to you a latest open source javaScript runtime: Bun.js.
Just got a 26.1k star in less than a month! It looks like it's going to be a big competitor to and Node.js ! Deno
Node.js Unlike the traditional runtime javaScript , Bun.js the packager, transpiler, task runner and npm client are directly built in, which means that you Webpack/Rollup/esbuild/Snowpack/Parcel/Rome/swc/babel can run it directly without any need TypeScript、JSX!
In addition, Bun.js hundreds of sums are natively supported Node.js , Web APIincluding functions of approx 90% ( Node-API etc. fs、path、Buffer ).
Bun.js The goal is to run most of the world outside of the browser, JavaScriptbring performance and complexity enhancements to your future infrastructure, and increase developer productivity with better, simpler tools!
How is the performance?
Server-side rendering: HTTP requests processed per second
Loading a huge sqlite table: Average queries per second
FFI: operations per second
Why so fast?
And Node.js、Deno different, Bun.js it is not based on V8 the engine, it directly selects the JavaScriptCore engine, and its execution speed tends V8 to be faster than other more traditional engines.
Also, Bun.js being written in a low-level programming language with manual memory management, low ZIG -level control over memory, no hidden control flow, is probably the secret to its very good performance.
Bun.js 的大部分内容都是完全从零开始编写的，包括 JSX/TypeScript 转译器、npm 客户端、打包器、SQLite 客户端、HTTP 客户端、WebSocket 客户端等等。
有哪些能力？
Web API：对fetch、WebSocket、 ReadableStream等API都提供了内置支持Node.js模块：Bun实现了Node.js的模块解析算法，同时支持ESM和CommonJS，但Bun内部使用ESM。- 支持转译大量文件类型，你可以直接运行
TypeScript、JSX，甚至支持各种tsconfig.json中的配置。
| Input | Loader | Output |
|---|---|---|
| .js | JSX + JavaScript | .js |
| .jsx | JSX + JavaScript | .js |
| .ts | TypeScript + JavaScript | .js |
| .tsx | TypeScript + JSX + JavaScript | .js |
| .mjs | JavaScript | .js |
| .cjs | JavaScript | .js |
| .mts | TypeScript | .js |
| .cts | TypeScript | .js |
| .toml | TOML | .js |
| .css | CSS | .css |
| .env | Env | N/A |
| .* | file | string |
Bun.write使用最快的系统调用，实现写入、复制、管道、发送和克隆文件。- 自动加载环境变量
.env文件，不需要再require("dotenv").load() - 附带一个内置的快速
SQLite3客户端bun:sqlite Bun.js实现了大部分Node-API(N-API)，大部分Node.js原生模块都可以正常工作。bun:ffi可以使用低成本的外部函数接口从JavaScript调用本机代码(据测试比napi快 5 倍 、比Deno快100倍)
- Native support for an ever-growing
Node.jslist of core modules as well as global variables such asBufferandprocess
try it
Install Bun CLI:
curl https://bun.sh/install | bash
Bun The HTTP server is Request built on standards Response such as :Web
// http.js
export default {
port: 3000,
fetch(request) {
return new Response("Hi, ConardLi！Welcome to Bun!");
},
};
bun Run it with :
bun run http.js
Then open it in your browser http://localhost:3000.
- See more examples: github.com/Jarred-Sumn…
- Check out the official documentation: github.com/Jarred-Sumn…
CLI Commands: : Scripts in and files and files bun runcan be run directly .JavaScriptTypeScriptpackage.jsonscripts
According to tests,
bunrunning the script is 30 times fasterpackage.jsonthannpmrunning the script.package.json
CLI command: bun install: Compatible npm package manager, use the fastest system call to copy files.
According to tests, bun installs packages 20 times faster than npm.
CLI Commands: bun wiptest: A similar Jest test runner for built- bun in JavaScript and TypeScript projects.
Such bunjs is expected to become a member of the replacement node.