Bun v1.2.14

This release fixes 39 issues (addressing 179 👍) and adds support for catalogs in bun install, a --react flag for bun init, improved HTTP routing with method-specific routes, better TypeScript default module settings, fixes a HTTPS proxy issue impacting Codex, and several Node.js compatibility improvements including worker_threads reliability enhancements and http2 server improvements.

To install Bun

curl -fsSL https://bun.sh/install | bash

npm install -g bun

powershell -c "irm bun.sh/install.ps1|iex"

scoop install bun

brew tap oven-sh/bun

brew install bun

docker pull oven/bun

docker run --rm --init --ulimit memlock=-1:-1 oven/bun

To upgrade Bun

bun upgrade

Catalogs in bun install

Bun now supports catalogs, a powerful way to manage common dependency versions across monorepo workspaces.

How catalogs work

Define dependency versions once in the root package.json and reference them throughout your packages with the catalog: protocol.

{
  "workspaces": {
    "packages": ["packages/*"],
    "catalog": {
      "react": "^19.0.0",
      "zod": "4.0.0-beta.1"
    },
  }
}

In your workspace packages, reference the dependency with the catalog: protocol.

{
  "name": "my-package",
  "dependencies": {
    "react": "catalog:"
  }
}

Catalogs let you specify a single version of a dependency across all packages. When publishing or packing, Bun automatically replaces the catalog reference with the version specified in the catalog. That way, if you want to ensure your workspace uses the same version of a package like react, you only have to update it in one place instead of every package.

Thanks to @dylan-conway for the contribution!

zstd support in fetch

Bun now supports Zstandard (zstd) decompression in the HTTP client. The HTTP client will automatically decompress responses with Content-Encoding: zstd and can request zstd-compressed responses by including zstd in the Accept-Encoding header. The default Accept-Encoding header is now gzip, deflate, br, zstd.

// Request a zstd-compressed response
const response = await fetch("https://example.com", {
  headers: {
    "Accept-Encoding": "zstd",
  },
});

// Decompress the response
const decompressed = await response.text();

Bun.zstdCompress and Bun.zstdDecompress

Additionally, Bun now provides utilities for working with zstd compression directly:

// Compress data using zstd
const compressed = Bun.zstdCompressSync("hello world", { level: 5 });

// Async compression
const compressedAsync = await Bun.zstdCompress("hello world");

// Decompress zstd data
const decompressed = Bun.zstdDecompressSync(compressed);

// Async decompression
const decompressedAsync = await Bun.zstdDecompress(compressed);

--react flag for bun init

bun init now supports a --react flag to quickly bootstrap a React project with popular configurations including Tailwind CSS and shadcn/ui.

bun init --react

bun init --react=tailwind

bun init --react=shadcn

This builds on the React templates added in Bun v1.2.3 to support specifying a React template without a tty, which is useful for projects & tooling running bun init programmatically.

Better TypeScript Default Module Setting

Bun's default TypeScript configuration now uses "module": "Preserve" instead of "module": "ESNext". This is a more appropriate default as it preserves the module syntax you write rather than transforming it, giving you more control over your code output. You can learn more about 'Preserve' on the TypeScript website.

// tsconfig.json
{
  "compilerOptions": {
    // Old setting
    // "module": "ESNext",

    // New setting - preserves the exact module syntax you write
    "module": "Preserve"
  }
}

This change applies to default configurations for new projects and is recommended for existing projects.

Thanks to @mattpocock and @alii for the contribution!

Improved HTTP routing

Bun.serve() routes now supports applying routes to specific HTTP methods for both static Response objects and HTML imports.

We've also fixed a bug where /* would have higher precedence than method-specific routes.

Fixed: HTTPS client proxy reliability impacting Codex

A reliability issue with Bun's HTTPS client when using proxies has been fixed. This issue impacted Codex, leading to hangs when installing dependencies.

Thanks to @cirospaciari for the fix!

Node.js compatibility improvements

worker_threads reliability improvements

We've continued to make improvements to Worker reliability. One difference between Web Workers and worker_threads is that when an unhandled exception occurs in a Web Worker, the ErrorEvent emitted only contains a stringified representation of the error. Node.js worker_threads on the other hand, will emit an Error object.

// Web Worker
new Worker("worker.js").onerror = (event) => {
  console.log(event.constructor.name); // "ErrorEvent"
  console.log(event.message); // "Uncaught Error: test"
};

// worker_threads
import { Worker as NodeWorker } from "node:worker_threads";
const worker = new NodeWorker("worker.js");
worker.on("error", (error) => {
  console.log(error.constructor.name); // "Error"
  console.log(error.message); // "test"
});

Now, worker_threads in Bun will emit an Error object when an unhandled exception occurs instead of the stringified error event from Web Workers. This improves the quality of error messages when using worker_threads.

Thanks to @190n for the contribution!

node:http2 server improvements

Bun's node:http2 implementation now supports maxSendHeaderBlockLength, which limits the size of the header block that can be sent in a single frame. This is useful for preventing memory issues when sending large headers.

const server = http2.createServer({
  maxSendHeaderBlockLength: 1024 * 1024, // 1MB
});
// ...

For the client, we've also added support for setNextStreamID, which allows you to set the next stream ID for the http2 connection.

Thanks to @cirospaciari for the contribution!

Additional bugfixes for Node.js compatibility:

• numeric header names in node:http server's request.headers work as expected.
• BroadcastChannel.prototype.unref() would return undefined instead of the BroadcastChannel instance.
• ERR_EVENT_RECURSION is now thrown when expected.

Bugfixes

• bun --install=force <script.ts> would not respect the --install=force flag.
• new TextDecoder("utf-8", undefined) would throw an error instead of ignoring the undefined argument.
• HTTP/1.1 chunked encoding extension are no longer rejected
• inconsistent floating point math results in JavaScript transpiler compared to runtime behavior.
• CSS custom property parser edgecase
• util.inherits in bun build --target=browser did not exist. Now it exists.

Thanks to 13 contributors!

• @190n
• @alii
• @bradeneverson
• @cirospaciari
• @devsdk
• @dylan-conway
• @electroid
• @huiyifyj
• @jarred-sumner
• @nektro
• @pfgithub
• @riskymh
• @sverp