---
title: Bun v0.7.2
description: worker_threads, BroadcastChannel, diagnostics_channel, Node.js compatibility improvements, bun ., bugfixes and 2 memory leaks fixed
date: "2023-08-03T12:00:00+00:00"
author: jarred
draft: false
---
Bun v0.7.2 adds support for `node:worker_threads`, `node:diagnostics_channel`, [`BroadcastChannel`](https://developer.mozilla.org/en-US/docs/Web/API/BroadcastChannel), improves compatibility with Node.js, and fixes a couple nasty memory leaks.
{% callout %}
We're hiring C/C++ and Zig engineers to build the future of JavaScript! [Join our team →](/careers)
{% /callout %}
Bun is an incredibly fast JavaScript runtime, bundler, transpiler, and package manager — all in one. Over the past couple months, we've been releasing a lot of changes to Bun recently, here's a recap in case you missed it:
- [`v0.6.12`](/blog/bun-v0.6.12) - Sourcemap support in `Error.stack`, `Bun.file().exists()`, and Node.js bug fixes.
- [`v0.6.13`](/blog/bun-v0.6.13) - Implemented mock `Date`, faster base64 encoding, and fixes for `WebSocket` and `node:tls`.
- [`v0.6.14`](/blog/bun-v0.6.14) - `process.memoryUsage()`, `process.cpuUsage()`, `process.on('beforeExit', cb)`, `process.on('exit', cb)` and crash fixes
- [`v0.7.0`](/blog/bun-v0.7.0) - Web Workers, --smol, structuredClone(), WebSocket reliability improvements, node:tls fixes, and more.
- [`v0.7.1`](/blog/bun-v0.7.1) - ES Modules load 30% - 250% faster, fs.watch fixes, and lots of node:fs compatibility improvements.
To install Bun:
{% codetabs %}
```sh#curl
$ curl -fsSL https://bun.sh/install | bash
```
```sh#npm
$ npm install -g bun
```
```sh#brew
$ brew tap oven-sh/bun
$ brew install bun
```
```sh#docker
$ docker pull oven/bun
$ docker run --rm --init --ulimit memlock=-1:-1 oven/bun
```
{% /codetabs %}
To upgrade Bun:
```sh
$ bun upgrade
```
## Node.js worker_threads
You can now use the `node:worker_threads` module in Bun. `Worker` remains a global variable, but you can now use packages & frameworks that depend on `node:worker_threads` in Bun.
```js
import { Worker } from "node:worker_threads";
const worker = new Worker("./worker.js");
```
## `bun .` - run the main file
You can now run a project in Bun with `bun .` when you don't want to type out a path to a file. It is equivalent to doing `import '.'`
```sh
$ bun .
```
## BroadcastChannel
The [`BroadcastChannel`](https://developer.mozilla.org/en-US/docs/Web/API/BroadcastChannel) API is now available in Bun. It allows you to publish-subscribe to messages across multiple `Worker` threads and the main thread. This is a new global variable, so you can use it without importing anything just like in web browsers.
```js
const channel = new BroadcastChannel("my-channel");
const message = { hello: "world" };
channel.onmessage = (event) => {
console.log(event.data); // { hello: "world" }
};
channel.postMessage(message);
```
Thanks to [@dylan-conway](https://github.com/dylan-conway) for getting this working in Bun and the WebKit/Safari team for the original implementation.
## postMessage() now supports `Error`
You can now use `postMessage` and `structuredClone()` to clone `Error` objects.
```js
const error = new Error("hello world");
const clone = structuredClone(error);
console.log(clone.message); // "hello world"
```
## Node.js `node:diagnostics_channel` support
You can now use the `node:diagnostics_channel` module in Bun. The node:diagnostics_channel module provides an API to create named channels to report arbitrary message data for diagnostics purposes.
## Creating new TypedArray gets up to 40x faster
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{% /raw %}
## Module resolution change: `browser` and `module` exports conditions
Bun no longer respects the `"browser"` or `"module"` package.json `"exports"` conditions. This addresses bugs impacting Astro CLI, axios, and more.
- Bun is not a web browser, so Bun should not use the `"browser"` package.json exports condition.
- The `"module"` exports condition is used by older versions of tslib and that breaks packages which rely on tslib. We still support this in `bun build`, but not at runtime.
The list of package.json `"exports"` conditions Bun respects at runtime is now as follows:
- `"bun"`
- `"worker"`
- `"node"`
- `"default"`
When coming from an ES module, `"import"` is used and when coming from a CommonJS module, `"require"` is used as well.
This is technically a breaking change, but it will usually be more of a "fixing" change.
## 2 memory leaks fixed
A memory leak in strong references held by native code in Bun has been fixed. This is a leak of about 16 bytes, however it quickly adds up in long-running processes.
{% raw %}
{% /raw %}
A memory leak in `response.clone()` has been fixed. The headers object was cloned twice.
{% raw %}
{% /raw %}
## Bugfixes
We also fixed some bugs
### `PrintingErrorWriteFailed` bug fixed
A regression from the async transpiler changes caused some imports to fail with `PrintingErrorWriteFailed`. This has been fixed.
### `file` loader bug fix
A regression from the async transpiler changes caused `file` loader imports to fail to load unless explicitly passed via `--loader`. This has been fixed.
### `require('node:module')` is now a `Module` constructor
`require('node:module')` is now a `Module` constructor, as it is in Node.js.
### `bun install --production` with workspaces
A bug causing packages to not be updated in the lockfile when `--production` was used in a workspace has been fixed.
### node:http file upload bug has been fixed
[A bug](https://github.com/oven-sh/bun/issues/3116) where binary file uploads via `node:http` would produce incorrectly-encoded data has been fixed by [@Hanaasagi](https://github.com/Hanaasagi). Thanks @Hanaasagi!
## Internals changes
We migrated our JavaScript builtins from ES modules to CommonJS, which improves start time for `"crypto"` by about 30% and fixed a crash when importing `"astro"`.
## Changelog
[View the complete changelog](https://github.com/oven-sh/bun/compare/bun-v0.7.1...bun-v0.7.2)