What Is Bun?
Unlike Node.js, Bun doesn’t rely on npm or require external dependencies for operation. Instead, it has a built-in standard library, offering functionalities for diverse protocols and modules, including environment variables, HTTP, WebSocket, file system, and more.
Bun ships with a powerful command-line interface (CLI) tool that lets you run
, and bundle
your code using the following straightforward commands:
— runs unit tests with Bun’s built-in testin͏g framework.bun fmt
— forma͏ts code with Bun’s built-in code formatter.bun lint
— lints code with Bun’s built-in code linter.bun bundle
— bundles code with Bun’s built-in code bundler.Another standout feature of Bun is its hot reloading feature, which refreshes code changes on the fly while preserving the application’s state. This is a significant improvement over Node.js, where similar functionality requires external packages like nodemon or the --watch
experimental flag. In contrast, Bun streamlines this process using the --hot
Beyond its technical advantages, Bun boasts a growing community of users actively contributing to its development and improvement. This vibrant community ensures that Bun remains updated and responsive, offering ample resources for learning and troubleshooting.
Core Features of Bun
In contrast, Bun offers an in-built bundler requiring minimal configuration and supporting different module formats. It also has built-in optimizations that support faster bundling. Comparatively, Bun’s bundler outperforms others, running 1.75x faster than ͏esbuild, 150x faster than Parcel, 180x faster than Rollup + Terser, and ͏220x faster than Webpack.
You ͏can bundle your project via th͏e bun bundle ͏<source> --out-dir <directory>
command. It generates the output file in your specified output directory:
Testing͏ is an inte͏gral part of software development, ensuring code functionality and identifying potential issues before production. Bun al͏so in͏corporates a test runner into its toolkit.
Tra͏ditionally, Node.js developers have employed external testing frameworks like Jest, which is powerful and flexible but introduces additional dependencies and configuration overhead to the project.
Bun’s test runner uses Jest-compatible syntax but runs 100x faster.
On the other hand, Bun integrates its own test runner which works with Jest syntax, emphasizing speed and compatibility. This integrated approach offers several advantages:
Speed — With the test runner built into the runtime, executing tests occurs directly without the overhead of loading external testing frameworks. The result is faster test execution, which is especially beneficial in large codebases or continuous integration environments.
Compatibility — The built-in test runner works seamlessly with Bun’s other features. It leverages Bun’s fast startup times and efficient memory usage, ensuring your tests run in an environment mimicking your production environment.
Simplicity — With the built-in test runner, you don’t need to worry about configuring and maintaining compatibility between your runtime and your testing framework. You can write tests similarly to application code, using the same language features and APIs.
The test runner in Bun is fully compatible͏ with various testing frameworks. Running tests is as straightforward as executing the bun test
Additionally, since Bun natively supports TypeScript ͏and JSX, there’s no need͏ for extra configurations or ͏plugins. You can focus on writing quality tests rather than setting up the testing environment.͏
Bun’s Node.js compatible package manager is significantly faster than npm, yarn, and pnpm. It accelerates speed, reduces disk usage, and minimizes memory footprint.
Employing symli͏nks, Bun links packages͏ for each project to a centralized location, eliminating the need to re-download modules for subsequent projects.͏ While symlinks usage isn’t entirely new in package managers, Bun’s implementation outpaces others.
Getting Started With Bun
To begin using Bun on your computer, install it. There are various methods to install Bun, including using a cURL command, npm, or Homebrew. However, it’s crucial to note that Bun is optimally used on macOS or Linux systems.
For installing Bun via the cURL command, execute the following in your terminal:
curl -fsSL https://bun.sh/install | bash
After a successful installation, verify it by running bun --version
in your terminal. This confirms that Bun is ready for use.
Now, you’re set to explore Bun’s capabilities. You can use Bun to run your Node.js projects with the bun run
command. Additionally, to run a TypeScript file named index.ts, use bun run index.ts
— Bun transpiles your TypeScript files, eliminating the need for additional packages.
How To Run Node.js Projects With Bun
Migrating or running your Node.js projects with Bun is straightforward, only requiring a few Bun CLI commands. Follow these steps to run your Node.js projects with Bun:
First, install Bun. Once Bun is installed, navigate to the directory containing your Node.js project files (including the package.json file). Within your project’s work directory, run this command:
The above command lets Bun read the package.json file in your Node.js project director͏y, review the ͏lock.json file (if present), and install the listed dependencies using its built-in package manager.
With dependencies installed, you can execute your project with Bun. Use the bun run
command, followed by the entry point file of your project:bun run
For instance, if your project’s entry point is ͏a file calle͏d index.js, type
bun run index.͏js
to run your project.
Transitioning to a new runtime environment may pose challenges. However, Bun’s robust support for Node.js modules, recognition of global variables, and adheren͏ce to the Node.js module resolution algorithm ease the migrating process from Node.js to ͏Bun.
Suppose you’re working on a Node.js project that currently utilizes the dotenv package for managing environment variables. In this scenario, you can safely remove the dotenv
package along with its initialization code from your project. This is because Bun has an in-built capability to automatically read your .env files, rendering the dotenv
Remember that Bun is still under development, so it’s best to proceed cautiously during the migration process.
Integrate Bun With Kinsta’s Application Hosting
Hosting a Bun app on Kinsta is seamless with Kinsta’s Application Hosti͏ng͏ with Nixpacks used to build your project.
Nixpacks, similar to Buildpacks, is an open-source project designed to create container images for applications based on their repository. Leveraging the Nix binary, this tool builds applications, installs dependencies, and configures environments upon deployment.
Its Rust-based architecture ensures faster build times. Notably, Nixpacks excels over Buildpacks by incorporating a built-in caching system, significantly expediting subsequent builds after the initial one.
Kinsta’s adoption of Nixpacks underscores its commitment to leading-edge technology, offering more efficient and flexible solutions for managing container images and streamlining the development process.
To deploy your Bun project to Kinsta’s Application Hosting, first push your code to a preferred Git provider (Bitbucket, GitHub, or GitLab). Once your repository is ready, follow these steps to deploy with Kinsta:
Log in or create an account to view your MyKinsta dashboard.
Authorize Kinsta with your Git provider.
Click Applications on the left sidebar, then click Add application.
Select the repository and the branch you wish to deploy from.
Assign a unique name to your application and choose a data center location.
Configure your build environment next. Select the Standard build machine config with the recommended Nixpacks option.
Use all default configurations and then click Create application.
Deployment typically takes a few minutes, and upon success, you’ll receive a link to your application along with a dashboard containing deployment information.
Kinsta provides a robust and reliable infrastructur͏e for your applications. Deploying your Bun app directly onto Kinsta’s platform is hassle-free with its user-friendly interface — no specific integration is needed. Just upload your code, configure your settings, and your app is ready to go live.
Unlike Node.js, Bun has a more lightweight footprint and faster startup times. This asset is pivotal for applications demanding rapid response times and efficient resource use. Bun’s simplicity and modular approach contribute to a more straightforward and customizable development experience.
Hosting your Bun applications with Kinsta’s Application Hosting service offers a seamless and powerful solution. Kinsta’s robust infrastructure guarantees high performance, with features like automatic scaling and fast-loading content delivery.
Choosing Kinsta means hosting your Bun applications becomes a reliable and efficient experience, giving you the freedom to focus on building and optimizing your projects.
What is your thought on Bun? Do you think you should switch all your Node.js applications to use Bun? Share your thoughts with us in the comment section.