heroku-buildpack-bun

Heroku buildpack for Bun.js - allows you to run Bun on Heroku.

Largely copied from the Deno buildpack and Node.js buildpack.

How to use

To add the buildpack to your Heroku app, visit the settings page for your app on Heroku, then under 'Buildpacks' add the URL https://github.com/jakeg/heroku-buildpack-bun.

You'll either need a Procfile in the root folder of your app (with eg web: bun index.js in it), or a package.json with a start script listed.

Pin a certain Bun version such as v1.1.20 with the BUN_VERSION environment variable (eg under 'Config Vars' on your app's Heroku settings page), or with a .bun-version, runtime.bun.txt or runtime.txt containing a single line for the pinned version. The version can be specified with or without a leading v eg v1.0.7 or 1.0.7 or any other Bun tags.

Support scripts

This buildpack automatically runs the following bun commands and scripts if defined in package.json.

• install (bun install)
• heroku-prebuild (bun run heroku-prebuild)
• build (bun run build)
• heroku-postbuild (bun run heroku-postbuild)

Optionally skip any of these steps with files named .skip-bun-install, .skip-bun-heroku-prebuild, .skip-bun-build or .skip-bun-heroku-postbuild.

Binding to correct port

Bind to env.PORT eg

import { env } from 'process'

const server = Bun.serve({
  port: env.PORT || 3000,
  fetch(request) {
    return new Response(`Welcome to Bun running on Heroku!`)
  },
})

console.log(`Listening on localhost:${server.port}`)

Potential issues

Use the Issues tab to report any issues.