Deno

Deno is a secure-by-default JavaScript and TypeScript runtime built by Deno Land Inc., founded by Ryan Dahl — the original creator of Node.js — to fix design regrets he had with Node. It ranks around #22 among web frameworks/runtimes at roughly 4% usage share. Developers pick it up for built-in TypeScript support with no separate compile step, a permissions system that requires explicit flags for file, network, and environment access, and a standard library that ships in the runtime itself.

Example

Deno ships a built-in Deno.serve API, so a working HTTP server needs no external framework or dependency install.

// server.ts
Deno.serve({ port: 8000 }, (req: Request) => {
  const url = new URL(req.url);

  if (url.pathname === "/") {
    return new Response("Hello from Deno!");
  }

  return new Response("Not found", { status: 404 });
});

Getting started

Install the Deno CLI, then run a file directly — TypeScript needs no build step, and permissions must be granted explicitly.

# install Deno (Windows PowerShell)
irm https://deno.land/install.ps1 | iex

# run a server, granting only network access
deno run --allow-net server.ts