What is rathole?

Rathole lets you expose a service running on a private network (like your home Wi-Fi) to the public internet, even when that network sits behind a router that blocks incoming connections. The classic example: you have a NAS or a home server at home and want to SSH into it from anywhere, but your home internet doesn't allow inbound connections. Rathole creates a tunnel so people can reach that home machine through a public server you control. It works as a pair: you run one piece on a server with a public IP address, and another piece on the private device. The private device reaches out to the public server and maintains an active connection. When someone connects to a specific port on your public server, the traffic gets tunneled through that existing connection back to your private device. You configure both sides with simple text files that specify addresses, ports, and shared secret tokens. Tokens are mandatory, and the project supports optional encryption so traffic between the two endpoints stays protected. This is useful for anyone who needs to expose a private service without changing router settings or paying for a VPN. Examples include accessing a home lab, running a game server from your living room, or reaching a development environment from a different location. The README notes that the project aims to be lighter on resources than similar tools like frp or ngrok, with a binary that can be made small enough for embedded devices like routers. It also supports hot-reloading the configuration so services can be added or removed without restarting. Notably, the project is built in Rust and emphasizes both performance and low memory consumption. The README is transparent that real-world gains depend on your network: if your internet connection is the bottleneck, the main benefit is lower resource usage rather than dramatically faster speeds. Encryption can be configured using the Noise Protocol or TLS, with no need for self-signed certificates in the Noise case. An HTTP API for configuration is listed as work in progress.