Deno 2 Has a Free Runtime That Runs Node.js Code — With Built-In TypeScript, Linting, and Testing

#typescript #webdev #node #deno

The Node.js Problem

Starting a new Node project means:

tsconfig.json for TypeScript
.eslintrc for linting
jest.config.js for testing
package.json for dependencies
node_modules with 1,000 folders

Deno 2 includes all of this out of the box. And now it runs your existing Node.js code.

What Deno 2 Gives You

Native TypeScript

// Just write TypeScript. No tsconfig. No compilation step.
const response = await fetch('https://api.github.com/users/denoland');
const user: { login: string; name: string } = await response.json();
console.log(user.name);

deno run main.ts  # Just works

Node.js Compatibility

import express from 'npm:express';

const app = express();
app.get('/', (req, res) => res.send('Hello from Deno!'));
app.listen(3000);

Deno 2 reads package.json. Uses node_modules if you want. Most npm packages work unchanged.

Built-In Tools

# Linting — no ESLint config needed
deno lint

# Formatting — no Prettier needed  
deno fmt

# Testing — no Jest/Vitest needed
deno test

# Type checking
deno check main.ts

# Benchmarking
deno bench

Permission System

# Explicit permissions — your script can't secretly access the network
deno run --allow-net --allow-read main.ts

# Or allow everything (like Node)
deno run -A main.ts

deno.json — One Config File

{
  "tasks": {
    "dev": "deno run -A --watch main.ts",
    "test": "deno test -A",
    "build": "deno compile main.ts"
  },
  "imports": {
    "@std/": "jsr:@std/"
  }
}

Replaces package.json, tsconfig.json, .eslintrc, jest.config, and prettier.config.

Compile to Single Binary

deno compile --output myapp main.ts
# Produces a single executable — no runtime needed
./myapp

Why This Matters

Deno 2 isn't fighting Node anymore — it's absorbing it. Run your existing Node code, but with TypeScript by default, security by default, and zero configuration. The future of JavaScript is simpler than its past.

Building Deno APIs that need web data? Check out my web scraping actors on Apify Store — structured data via API. For custom solutions, email spinov001@gmail.com.

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