Getting Started with Deno

Deno is a modern runtime for JavaScript and TypeScript that addresses many of the shortcomings of Node.js. Created by Ryan Dahl (the original creator of Node.js), Deno provides a secure-by-default environment with built-in TypeScript support.

Why Deno?

Security First

Unlike Node.js, Deno runs with restricted permissions by default. You must explicitly grant access to:

• File system operations
• Network access
• Environment variables
• Running subprocesses

# Explicit permission flags
deno run --allow-net --allow-read server.ts

Built-in TypeScript

No configuration needed - Deno understands TypeScript natively. Just write .ts files and run them directly:

interface User {
  name: string;
  email: string;
}

const user: User = {
  name: "Jordan",
  email: "jordan@example.com"
};

console.log(`Hello, ${user.name}!`);

Modern ES Modules

Deno uses ES modules exclusively and supports importing from URLs:

import { serve } from "https://deno.land/std@0.208.0/http/server.ts";

serve((req) => new Response("Hello World!"));

Key Features

1. Standard Library: Comprehensive, audited standard modules
2. Built-in Tools: Formatter, linter, test runner, and bundler included
3. Web Platform APIs: Uses familiar browser APIs like fetch, WebSocket
4. Dependency Management: No package.json or node_modules

Getting Started

Install Deno:

# macOS/Linux
curl -fsSL https://deno.land/install.sh | sh

# Windows
irm https://deno.land/install.ps1 | iex

Create your first server:

// server.ts
Deno.serve({ port: 8000 }, () => {
  return new Response("Hello from Deno!");
});

Run it:

deno run --allow-net server.ts

Conclusion

Deno represents a fresh take on JavaScript runtimes, learning from Node.js's mistakes and embracing modern standards. Whether you're building APIs, CLI tools, or web applications, Deno provides a secure and developer-friendly environment.

Ready to dive deeper? Check out the official Deno documentation and start building!