patrickjs/port-manager

Port Manager is a developer tool that finds available network ports on your machine, tells you what's using them, and lets you safely claim a port so another process won't grab it. Instead of wrestling with port conflicts when you're running multiple local services (a frontend dev server on 3000, a database on 5432, a test suite on 8080), you ask Port Manager "give me a free port near 3000" and it hands you one that's actually available, then holds it until you're done. The project is built as a hub-and-spoke system so multiple ways of using it (a command-line tool, code libraries, a macOS desktop app, even Raycast integration) all talk to the same underlying logic. You can call it from Node.js code, run it as a CLI command and parse JSON output, or click through a Mac app. All paths feed information to a shared "lease registry", essentially a file on disk that tracks which ports are claimed by which processes, so if your frontend build tool and your test runner both ask Port Manager for a port, they won't step on each other even if they run at slightly different times. The typical user is a developer with multiple local services running, or an AI agent (like GitHub Copilot or a custom coding assistant) that's spinning up servers and needs a way to find open ports without guessing or parsing obscure system commands. It's also built to play nice with existing Node.js packages like get-port and portfinder, you can swap Port Manager in without rewriting your code. A few details make this practical: you can reserve a port temporarily (a "soft" reservation that other cooperative tools will respect) or bind it for real (a hard lock that the OS recognizes). The macOS app can run as a background service that stays running between restarts, so it's always available to field port queries. And the whole thing is intentionally lightweight, it's not a firewall or a permission system, just a registry that helps well-behaved tools coordinate.