Deno is a fast, open-source, and fully Node-compatible JavaScript and TypeScript runtime built on Rust, designed to provide a highly secure and complete developer experience out of the box.

The main features of this tool include:

• Zero-Setup TypeScript & JSX: It runs TypeScript, JSX, and npm packages straight from the source with no compiler (tsc), bundler, or configuration files required.

• Fully Baked-In Toolchain: Rather than requiring developers to stitch together multiple external packages, Deno includes a built-in package manager, test runner, formatter, linter, task runner, type checker, coverage tool, workspace manager, benchmarker, doc generator, jupyter kernel, compiler, and desktop app builder.

• Granular Security Sandbox: By default, Deno blocks access to the file system, network, and environment variables. Permissions must be explicitly granted (e.g., using --allow-net or --allow-scripts for post-install scripts).

• A Faster Package Manager: It supports npm workspaces, reads npm, yarn, and pnpm lockfiles, and resolves packages from a global cache instead of a local node_modules folder, achieving ultra-fast install speeds.

• Native Web Standards: Deno implements the same fetch, Request, Response, and Crypto APIs used in modern web browsers. It is also quick to adopt cutting-edge standards-track features like Temporal, Set methods, and Iterator helpers.

• Deep Built-In Observability: Developers can instantly profile, debug, and trace applications with native OpenTelemetry (OTel) support, CPU profiling (producing flame graphs), and Chrome DevTools/VS Code debugging tools.

• Built-In Desktop App Builder: Using Deno Desktop, developers can compile cross-platform desktop applications (.app, .dmg, .msi, and .AppImage) directly from their web stack into a single binary, without shipping heavy Chromium or Electron runtimes.

• Optimized Performance: Built on Rust, Deno achieves high request throughput, low p99 latency, fast cold starts, and efficient peak memory usage when compared to other runtimes like Node and Bun.