corsis/PortFusion — reverse-engineered prompt

Build me a tiny cross platform command line tool called PortFusion that can tunnel normal TCP connections between computers. I want it to work for things like Remote Desktop, VNC, HTTP, HTTPS, SSH, or any service that just needs a port forwarded.

The main idea is simple. In reverse mode, I should be able to expose a port on one machine and have traffic secretly reach a service behind another network or firewall. In forward mode, I should be able to connect through a gateway machine to reach a service somewhere else. Keep the commands short and understandable, using host names and port numbers, with clear console output when it starts listening, connects, tunnels data, or hits an error.

Please make it lightweight and fast, with good concurrency so many connections can run at once. It should build as a Haskell Cabal project and be usable on Windows, Linux, macOS, and BSD if possible. Include a clear README with examples for the two main modes.