Deno

Modern JavaScript and TypeScript runtime built on V8 and Rust, offering zero-config TypeScript support and security-by-default permissions. Runs .ts and .js files directly with no build step, implements web standard APIs for consistency with the browser, and ships a complete built-in toolchain.

Created by the original designer of Node.js with lessons from that ecosystem. Deno restricts file, network, and environment access by default unless explicitly granted, reducing supply-chain risks compared to runtimes that grant broad permissions. Adopted for scripts, APIs, and edge workloads, with a large ecosystem of community modules and compatibility with npm for gradual migration from Node.

Key capabilities:

• Zero-config TypeScript, JSX, and modern ECMAScript with native type checking
• Secure-by-default permission model: file, network, and env access require explicit flags
• Built-in linter, test runner, formatter, and compiler for standalone executables
• Web standard APIs and URL-based imports, no centralized package registry
• npm and Node.js compatibility via package.json or direct npm: specifiers

Developers use Deno for automation scripts, HTTP servers, and CLI tools when they want fast startup without external tooling. The built-in deno run, deno test, and deno fmt replace separate Node toolchains. Teams migrating from Node can import npm packages directly while adopting URL imports and stricter permissions incrementally.