Bun in CI/CD Pipelines

🚀 Introduction to Bun in CI/CD Pipelines

Bun has taken the JavaScript world by storm with its ultra-fast runtime, built-in bundler, and native TypeScript support. But beyond local development, Bun can also significantly speed up Continuous Integration and Continuous Deployment (CI/CD) workflows.

In this tutorial, we'll explore how Bun fits into modern CI/CD pipelines, and how you can leverage it for faster builds, tests, and deployments.

⚙️ Why Use Bun in CI/CD?

Traditionally, tools like Node.js and npm/yarn dominate CI/CD setups. However, Bun brings some serious advantages:

• Speed: Bun installs dependencies and runs scripts faster than npm/yarn.
• Built-in Tools: Comes with its own bundler, test runner, and transpiler.
• Lightweight: Reduces third-party tooling requirements.
• Native TypeScript Support: No need for external compilers like tsc.

🔧 Setting Up Bun in a CI Pipeline

Let’s see how to set up Bun in a basic GitHub Actions CI workflow.

name: CI with Bun

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  test:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout Repository
        uses: actions/checkout@v3

      - name: Install Bun
        run: curl -fsSL https://bun.sh/install | bash

      - name: Add Bun to PATH
        run: echo 'export PATH="$HOME/.bun/bin:$PATH"' >> $GITHUB_ENV

      - name: Install Dependencies
        run: bun install

      - name: Run Tests
        run: bun test

This setup does everything: installs Bun, installs your dependencies using Bun, and runs your tests using Bun’s built-in test runner.

All of it executes faster than traditional setups.

📦 Caching Bun Dependencies

To make CI even faster, we can cache Bun's dependencies:

- name: Cache Bun
  uses: actions/cache@v3
  with:
    path: ~/.bun/install/cache
    key: ${{ runner.os }}-bun-${{ hashFiles('bun.lockb') }}
    restore-keys: |
      ${{ runner.os }}-bun-

This step will significantly reduce install time by avoiding unnecessary downloads.

🚚 Deployment Using Bun

After testing your code, you might want to deploy it. With Bun's built-in bundler and native support for full-stack apps, you can easily integrate deployment commands:

- name: Build Project
  run: bun run build

- name: Deploy
  run: bun run deploy

You can adapt these commands based on your preferred cloud provider like Vercel, Netlify, or a custom server.

🧪 Example: Testing a Bun App in CI

Here's a sample bun.test.ts to test in the pipeline:

import { expect, test } from "bun:test";

test("adds two numbers", () => {
  expect(1 + 2).toBe(3);
});

This test will automatically run when your CI workflow hits the bun test command.

🛠️ Tips for Using Bun in Production CI/CD

• Use Bun Lockfile: Commit bun.lockb to ensure consistent installs.
• Run in Docker: Use Bun in Docker containers for isolated environments.
• Use Linting: Though Bun lacks built-in linting, you can still run tools like ESLint alongside.

📈 Conclusion: Modern CI/CD with Bun

Incorporating Bun into your CI/CD pipelines can drastically improve performance, reduce dependencies, and streamline your workflows. Whether you’re running tests, building, or deploying, Bun offers a modern, fast, and all-in-one toolchain that fits perfectly into DevOps pipelines.

As more tooling evolves around Bun, expect it to become a first-class citizen in CI/CD environments.

Make the switch, speed things up, and enjoy a smoother developer experience with Bun in your CI/CD!