Deno

Deno is a modern JavaScript and TypeScript runtime created by Ryan Dahl, the original creator of Node.js, in 2018, designed to address the design mistakes and security issues of Node.js with first-class TypeScript support, secure-by-default permissions, a comprehensive standard library, web-standard APIs, and a built-in toolchain for formatting, linting, testing, and bundling, backed by Deno Land Inc. with over thirty million dollars in venture funding. The secure-by-default model requires explicit permission flags for file system access, network access, environment variable access, and high-resolution timer access, preventing untrusted dependencies from silently accessing sensitive system resources, with permissions specified through command-line flags or interactive prompts. The TypeScript support is built into the runtime, executing TypeScript files directly without external compilation, transpilation, or configuration, with type checking performed on-demand through the deno check command, eliminating the build tooling complexity required by Node.js TypeScript projects. The web standard APIs include fetch for HTTP requests, Web Workers for threading, WebSockets, URL parsing, TextEncoder and TextDecoder, Web Crypto API, and other browser-compatible interfaces, enabling code sharing between frontend and backend through consistent APIs. The standard library provides audited utilities for file I/O, networking, cryptography, HTTP serving, datetime manipulation, encoding, and data structures without external dependencies. The built-in toolchain includes deno fmt for formatting, deno lint for linting, deno test for testing, deno bundle for bundling, and deno compile for creating standalone executables. The Deno Deploy platform provides global edge deployment. Designed for JavaScript and TypeScript developers seeking a modern, secure runtime.