Guides · Docs

Overview

1

Guides

Code samples and walkthroughs for common tasks with Bun

Deployment

6

Deploy a Bun application on Vercel

Deploy a Bun application on Railway

Deploy a Bun application to Railway from the CLI or dashboard, with optional PostgreSQL setup and automatic SSL

Deploy a Bun application on Render

Deploy a Bun application on AWS Lambda

Deploy a Bun application on DigitalOcean

Deploy a Bun application on Google Cloud Run

Runtime & Debugging

9

Install TypeScript declarations for Bun

Re-map import paths

Debugging Bun with the VS Code extension

Debugging Bun with the web debugger

Inspect memory usage using V8 heap snapshots

Build-time constants with --define

Define and replace static globals & constants

Install and run Bun in GitHub Actions

Codesign a single-file JavaScript executable on macOS

Fix the "can't be opened because it is from an unidentified developer" Gatekeeper warning when running your JavaScript executable.

Utilities

19

Upgrade Bun to the latest version

Detect when code is executed with Bun

Get the current Bun version

Hash a password

Generate a UUID

Encode and decode base64 data

Compress and decompress data with gzip

Compress and decompress data with DEFLATE

Escape an HTML string

Check if two objects are deeply equal

Sleep for a fixed number of milliseconds

Convert a file URL to an absolute path

Convert an absolute path to a file URL

Get the path to an executable bin file

Get the directory of the current file

Get the file name of the current file

Get the absolute path of the current file

Check if the current file is the entrypoint

Get the absolute path to the current entrypoint

Ecosystem & Frameworks

27

Build an app with Astro and Bun

Create a Discord bot

Containerize a Bun application with Docker

Use Drizzle ORM with Bun

Use Gel with Bun

Build an HTTP server using Elysia and Bun

Build an HTTP server using Express and Bun

Build an HTTP server using Hono and Bun

Read and write data to MongoDB using Mongoose and Bun

Use Neon Postgres through Drizzle ORM

Use Neon's Serverless Postgres with Bun

Build an app with Next.js and Bun

Build an app with Nuxt and Bun

Run Bun as a daemon with PM2

Use Prisma with Bun

Use Prisma Postgres with Bun

Build an app with Qwik and Bun

Build a React app with Bun

Build an app with Remix and Bun

Use TanStack Start with Bun

Add Sentry to a Bun app

Build an app with SolidStart and Bun

Server-side render (SSR) a React component

Build an app with SvelteKit and Bun

Run Bun as a daemon with systemd

Build a frontend using Vite and Bun

Bun Redis with Upstash

HTTP & Networking

13

Common HTTP server usage

Write a simple HTTP server

Send an HTTP request using fetch

Hot reload an HTTP server

Start a cluster of HTTP servers

Run multiple HTTP servers concurrently with the "reusePort" option to share the same port across multiple processes

Configure TLS on an HTTP server

Proxy HTTP requests using fetch()

Stream a file as an HTTP Response

Upload files via HTTP using FormData

fetch with unix domain sockets in Bun

Streaming HTTP Server with Async Iterators

Server-Sent Events (SSE) with Bun

Streaming HTTP Server with Node.js Streams

WebSocket

4

Build a simple WebSocket server

Build a publish-subscribe WebSocket server

Set per-socket contextual data on a WebSocket

Enable compression for WebSocket messages

Processes & System

13

Spawn a child process

Read stdout from a child process

Read stderr from a child process

Parse command-line arguments

Read from stdin

Spawn a child process and communicate using IPC

Listen for CTRL+C

Listen to OS signals

Get the process uptime in nanoseconds

Run a Shell Command

Set a time zone in Bun

Set environment variables

Read environment variables

Package Manager

17

Add a dependency

Add a development dependency

Add an optional dependency

Add a peer dependency

Add a Git dependency

Add a tarball dependency

Install a package under a different name

Configuring a monorepo using workspaces

Override the default npm registry for bun install

Configure a private registry for an organization scope with bun install

Using bun install with an Azure Artifacts npm registry

Using bun install with Artifactory

Add a trusted dependency

Generate a yarn-compatible lockfile

Migrate from npm install to bun install

Configure git to diff Bun's lockb lockfile

Install dependencies with Bun in GitHub Actions

Test Runner

19

Run your tests with the Bun test runner

Run tests in watch mode with Bun

Migrate from Jest to Bun's test runner

Mock functions in `bun test`

Spy on methods in `bun test`

Set the system time in Bun's test runner

Use snapshot testing in `bun test`

Update snapshots in `bun test`

Generate code coverage reports with the Bun test runner

Set a code coverage threshold with the Bun test runner

Selectively run tests concurrently with glob patterns

Set a glob pattern to decide which tests from which files run in parallel

Skip tests with the Bun test runner

Mark a test as a "todo" with the Bun test runner

Set a per-test timeout with the Bun test runner

Bail early with the Bun test runner

Re-run tests multiple times with the Bun test runner

Using Testing Library with Bun

Write browser DOM tests with Bun and happy-dom

import, require, and test Svelte components with bun test

Module System

6

Import a HTML file as text

File System

21

HTML Processing

2

Extract links from a webpage using HTMLRewriter

Extract social share images and Open Graph tags

Binary Data

22

Streams

12

Convert a ReadableStream to a string

Convert a ReadableStream to JSON

Convert a ReadableStream to a Blob

Convert a ReadableStream to a Buffer

Convert a ReadableStream to an ArrayBuffer

Convert a ReadableStream to a Uint8Array

Convert a ReadableStream to an array of chunks

Convert a Node.js Readable to a string

Convert a Node.js Readable to JSON

Convert a Node.js Readable to a Blob

Convert a Node.js Readable to an Uint8Array

Convert a Node.js Readable to an ArrayBuffer