Deno is a new way to write server-side JavaScript it solves many of the problems of nodejs and was even created by the same guy (Ryan Dahl).
like node it uses the v8 JavaScript engine under the hood but the rest of the runtime is implemented in rust and typescript.

Deno and Node.js are both JavaScript runtime environments, but they have some key differences:

Modules:

Node.js uses a centralized package manager (npm), while Deno uses modules directly from URL imports.

Security:

Deno operates with a security-first mindset and runs scripts in a sandbox environment by default, while in Node.js, scripts have access to the file system and network by default.

TypeScript:

Node.js supports TypeScript, but it must be transpiled to JavaScript, while Deno includes TypeScript support out of the box.

Standard Library:

Node.js has a large standard library, while Deno provides a comprehensive standard library for its runtime environment, which includes modules for HTTP, WebSockets, and more.

Package Management:

Node.js relies on npm for package management, which can result in versioning issues, while Deno operates without a centralized package manager and relies on importing modules directly from URLs.

Background Threads:

Node.js uses a separate thread pool for background operations, while Deno runs all code in a single thread.

Here is an example of how to create a simple HTTP endpoint using both Deno and Node.js:

Deno

import { serve } from "https://deno.land/std/http/server.ts";
const server = serve({ port: 8000 });
console.log("Listening on http://localhost:8000/");
for await (const req of server) {
  req.respond({ body: "Hello World\n" });
}

Node.js

const http = require('http');
const server = http.createServer((req, res) => {
  res.end('Hello World\n');
});
server.listen(8000, () => {
  console.log('Listening on http://localhost:8000/');
});

Overall, Deno aims to provide a more secure, modern, and streamlined experience for JavaScript development but it is still relatively new and has limited community support as compared to Node.js.

Worths watching videos to explore more:

• Introduce: https://www.youtube.com/watch?v=F0G9lZ7gecE
• Example with Prisma, Deno: https://www.youtube.com/watch?v=P8VzA_XSF8w

Caveat: if you are going to use Deno in a monorepo to be able to use common model with React or etc that is based on Nodejs, there is an issue, since using implicit .ts extension is required in Deno https://github.com/denoland/deno/issues/2506

Let me know in the comments below thanks for reading, will create another comparison with bun make sure to follow to not miss that.
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