What is Bun?
Bun is a new Javascript runtime that focuses on simplicity, performance and developer experience. It has been built with the lessons from NodeJs in mind to minimise some of the common pitfalls of a Javascript runtime.
Bun has been built to minimise and abstract away a lot of the complexities from NodeJs to allow developers to focus on clean, maintainable, performant code.
Getting Started
- Install Bun for your OS as per the official Bun instructions
- Create a folder for your Bun project code files to live.
- In a terminal for the new folder run
bun initto set up the Bun project - Create an app.ts file in the folder
Creating the Bun Application
Open the app.ts file in your code editor of choice and add the following code:
const server = Bun.serve({
port: 3000,
fetch(request) {
return new Response("Welcome to Bun!");
},
});
console.log(`Listening on ${server.url}`);
If you are familiar with the Express framework, this should look very familiar.
This code snippet creates the bun app, sets up a basic response for the server, configures a port and starts the server.
Running the Server
Back in your terminal with the project folder open, run bun app.ts
In a browser, you can now navigate to http://localhost:3000 which will present you with the text 'Welcome to Bun!'
Conclusion
As shown above, the Bun framework provides a simple and effective way to create an HTTP server or API. This allows you to focus on writing clean, maintainable and performant code.