Port Zero

Port Zero solves a problem every developer knows but rarely thinks about until it bites them. You start a server, it grabs a port, and later another process wants the same one. The error message appears, EADDRINUSE, and now you're hunting through terminals or rebooting containers. Port Zero sidesteps all of that by letting you set every port to zero and giving each process a stable domain instead.

The way it works is straightforward. You configure your dev server with an environment variable that assigns it a domain like web.myapp.portzero.local. The tool handles port allocation automatically, and you access your service through the domain rather than remembering numbers. That domain stays consistent across restarts, which means bookmarks, OAuth redirects, and webhook URLs don't break every time something changes.

For local development this runs free and stays entirely on your machine. Tunnels resolve without network calls. Where it gets more interesting is the cloud tunnel feature, which gives you a public HTTPS URL to share your local app with a phone, tablet, or someone else reviewing your work. That's useful for webhook testing, mobile debugging, or quick demos without deploying to staging.

The tool supports macOS, Linux, and Windows through installers and a CLI. There's a team layer on top for organizations that want governance, approval workflows, and shared tunnel access without everyone managing their own credentials. An AI agent integration via Model Context Protocol is also available for automation scenarios.

Port Zero is open source under the GPL v3 license for the local tunnel functionality. Cloud tunnels and team features move into paid territory. The Professional tier runs forty nine dollars a month for unlimited cloud tunnels, and the Team plan at one hundred forty nine dollars a month adds multiple members and approval workflows. Enterprise pricing is custom.

If you've ever juggled multiple git worktrees, run several microservices locally, or burned time on port collisions across containers, this is aimed at that friction. It's a small tool that targets a small but persistent annoyance, and the free local tier means you can test whether it fits your workflow before paying for cloud features. The value scales with how often you share local work externally or coordinate across a team.