Deno 2.0: Node Compatibility and the Future of JavaScript Runtimes

Deno 2.0 achieves what many thought impossible: full Node.js compatibility while maintaining Deno's security-first philosophy and modern developer experience.

Node.js Compatibility

# Run Node.js projects directly
deno run --allow-all npm:express

# Import from npm
import express from "npm:express";
const app = express();
app.get("/", (req, res) => res.send("Hello!"));
app.listen(3000);

New Features in Deno 2.0

• package.json support: Full compatibility with Node projects
• Workspaces: Monorepo support out of the box
• Long-term support: LTS releases for enterprise
• Improved performance: Faster startup and execution

Security Model

Deno's permissions remain opt-in:

# Explicit permissions
deno run --allow-net --allow-read server.ts

# Or allow all (not recommended for production)
deno run --allow-all server.ts

Migration from Node.js

1. Remove node_modules (use Deno's caching)
2. Update imports to use npm: specifier or jsr:
3. Add permission flags to run commands
4. Test thoroughly with Deno's test runner