How do I initialize and run your first project?

# Create Project ```bash den o init hello_deno cd hello_deno ``` This creates: - `deno.json`: Config file - `main.ts`: Adds two numbers - `main_test.ts`: Test file # Run the Program ```bash den o run main.ts ``` Output: `Add 2 + 3 = 5` # Run Tests ```bash den o test ``` Output: `ok | 1 passed` Edit `main.ts` to experiment with TypeScript—no setup needed!

How do I understand and apply permissions?

# Deno's Security Model Deno requires explicit permissions (secure by default). # Examples **Read files:** `deno run --allow-read main.ts` **Network access:** `deno run --allow-net script.ts` **All permissions (dev only):** `deno run --allow-all script.ts` **Fetch example:** Create `fetch.ts`: ```typescript import { serve } from "jsr:@std/http"; serve(() => new Response("Secure Hello!")); ``` Run: `deno run --allow-net fetch.ts` Visit `http://localhost:8000`. Use specific: `--allow-net=localhost:8000`.

How do I manage modules and dependencies?

# Import Modules Deno imports from URLs/JS: ```typescript import { serve } from "jsr:@std/http"; ``` # Add Dependencies ```bash den o add jsr:@std/http ``` Updates `deno.json`: ```json { "imports": { "@std/http": "jsr:@std/http@^0.224.0" } } ``` # Run with Lock ```bash den o run --lock=deno.lock main.ts ``` Import npm: `import cowsay from "npm:cowsay";`

How do I build, test, and format a web server?

# Create Server `server.ts`: ```typescript import { serve } from "jsr:@std/http"; serve({ port: 8000, }, (req) => { const url = new URL(req.url); if (url.pathname === "/api/hello") { return new Response(JSON.stringify({ msg: "Hello Deno!" })); } return new Response("Home"); }); ``` # Tools ```bash # Format den o fmt # Lint den o lint # Test (add tests/) den o test # Run den o run --allow-net server.ts ``` Test: `curl http://localhost:8000/api/hello`

Master Deno: From Setup to Building Secure Apps

Q: How do I install deno and run hello world?

# Install Deno Choose based on your OS: **macOS/Linux (Shell):** ```bash curl -fsSL https://deno.land/install.sh | sh ``` **Windows (PowerShell):** ```powershell irm https://deno.land/install.ps1 | iex ``` Restart your terminal. Deno installs to `~/.deno/bin` (adds to PATH automatically). # Verify Installation ```bash den o --version ``` # Run Hello World ```bash den o run https://deno.land/std/examples/welcome.ts ``` Expected output: Welcome to Deno!

🧰

Instant Toolkit

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Step-by-Step Guide

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Install Deno

Choose based on your OS:

macOS/Linux (Shell):

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

Windows (PowerShell):

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

Restart your terminal. Deno installs to ~/.deno/bin (adds to PATH automatically).

Verify Installation

den o --version

Run Hello World

den o run https://deno.land/std/examples/welcome.ts

Expected output: Welcome to Deno!

Why this step matters:

-Builds a working Deno environment instantly
-Ensures compatibility before complex projects

15-30 minutes

Terminal/Command Prompt, Web Browser

$0

Definition of Done

•deno --version shows version (e.g., 2.0+)
•Hello World script executes successfully

Common Mistakes to Avoid

❌ Command not found after install

→Restart terminal or manually add ~/.deno/bin to PATH

❌ Permission denied on Unix

→Run chmod +x ~/.deno/bin/deno

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🎥
Suggested Videos

Deno Crash Course

Deno Course - Better than Node.js?

📚
Learning Resources

📖 Online Courses

Deno Course

beginner

freeCodeCamp

The Complete Deno.js Developer Course

beginner

Paid

Udemy

🌐 Helpful Websites

Deno Official Runtime Docs

documentation

Manual, installation, and API reference

Deno Examples & Tutorials

tutorials

Hands-on guides for servers, frameworks, testing

Deno GitHub

repository

Source code, releases, and community

🛠️ Useful Tools

Deno CLI

Developer Toolchain

Runtime, bundler, tester, formatter all-in-one

VS Code Deno Extension

IDE Extension

IntelliSense, debugging, and LSP support

Master Deno: From Setup to Building Secure Apps