Run Bun as a daemon with PM2

PM2 is a popular process manager that manages and runs your applications as daemons (background processes).

It offers features like process monitoring, automatic restarts, and easy scaling. Using a process manager is common when deploying a Bun application on a cloud-hosted virtual private server (VPS), as it:

• Keeps your Node.js application running continuously.
• Ensure high availability and reliability of your application.
• Monitor and manage multiple processes with ease.
• Simplify the deployment process.

You can use PM2 with Bun in two ways: as a CLI option or in a configuration file.

With --interpreter

To start your application with PM2 and Bun as the interpreter, open your terminal and run the following command:

$ pm2 start --interpreter ~/.bun/bin/bun index.ts

With a configuration file

Alternatively, you can create a PM2 configuration file. Create a file named pm2.config.js in your project directory and add the following content.

module.exports = {
  title: "app", // Name of your application
  script: "index.ts", // Entry point of your application
  interpreter: "bun", // Bun interpreter
  env: {
    PATH: `${process.env.HOME}/.bun/bin:${process.env.PATH}`, // Add "~/.bun/bin/bun" to PATH
  },
};

After saving the file, you can start your application with PM2

$ pm2 start pm2.config.js

That’s it! Your JavaScript/TypeScript web server is now running as a daemon with PM2 using Bun as the interpreter.