dep is a Node.js dependency installer that provides npm-compatible install, lock, and run commands with zero runtime dependencies. It resolves dependency trees, downloads packages, verifies integrity, and links them into node_modules. The architecture is modular with separate concerns for installation, lockfile generation, and script execution. Key features include workspace support, bounded concurrency, platform/engine constraint handling, optionalDependencies, peerDependencies, bundledDependencies, overrides, and aliased specifiers. The tool is designed for end-users rather than package authors, focusing on installing, locking, and running scripts.