Wi-Fi
Use an existing network: a hotspot, a tether, or your ordinary Wi-Fi. The Mac app can apply traffic rules to a chosen interface and gateway.
Wi-Fi · Modem · Radio
Bring your computer along, even when the connection is slow. Goblin Modem gives you controls for your links, a goTenna mesh for nearby computers, and a shell that travels with you.
Development preview / macOS + Linux

01 / Your connection, your choice
A slow or metered connection should still be useful. Bring up the link, see who is reachable, and choose which traffic gets to use your bandwidth.
Use an existing network: a hotspot, a tether, or your ordinary Wi-Fi. The Mac app can apply traffic rules to a chosen interface and gateway.
Bring up a serial PPP connection on the Mac, with the port, dial string and initialization commands your modem needs. Manage it alongside your radio.
Plug a goTenna Mesh radio into each computer. Mac and Linux share the radio driver, compressed IP transport, peer discovery and local SOCKS5 proxy.
The Mac has a native menu bar app with Wi-Fi/network, modem and radio controls. Linux has a browser GUI and desktop launcher for radio networking; configure its Wi-Fi or modem uplink with the operating system’s usual tools.
macOS / Protect a metered link
Background services can spend a narrow link’s bandwidth before you open an application. Goblin Modem uses macOS’s kernel packet filter, pf, to block traffic on the interface you choose and permit only the traffic your rules allow.
That includes system-level communication that an application-oriented userspace tool may miss or may not expose as a useful per-app control. Rules can match protocols, destinations and ports; for local TCP and UDP connections, they can also match the owning user or group. You can permit your SSH and Mosh sessions while keeping other users and background services off the link.
TripMode offers per-app controls through Apple’s Network Extension framework. Goblin Modem gives you interface-level packet rules, including a default block for traffic without a matching allow rule. This is a difference in control and filtering layer: current TripMode versions can also block system apps. Its documented Apple-app bypass affected macOS 11.0–11.1 and was fixed in 11.2. TripMode’s support notes ↗
These packet-filter controls are part of the Mac app. The Linux GUI manages the radio link; Linux uplink firewall policy remains with your system’s firewall tools.
02 / A network without a central router
Give the radios one shared network key and distinct identities. Computers discover names and addresses locally. There is no DHCP server to find first.
Some computers may have an Internet connection while others have only a radio. Turn on Share Internet on the connected computers to offer their uplinks to the mesh. A computer without Internet can then send selected applications through a nearby gateway, using its local SOCKS5 proxy.
Sharing starts off. Gateway priority, then discovered hop count, determines the automatic choice; you can also prefer a particular gateway.
Choose your Internet gateways ↗03 / A small terminal, doing real work
An 80 × 25 terminal, carried across two goTenna Mesh radios. Goblin Mosh connects to a shell running Goblin Purrfect, where equation source becomes a mathematical preview sent with DjVu compression.
Open a document, type a heading, enter the equation editor, and build the quadratic formula. The fraction and square root arrive as terminal graphics over the link. Finish the equation and save the document.
Our walkthrough connects a Mac and Linux computer with the same radio transport. Start with a short text command, then try an editor. The full-size equation reached the viewing terminal in about 83 seconds in this recording. Radio timing varies; playback keeps the waits visible.
Run Mosh between the radios ↗04 / Ready to try it?
Packages include the GUI, radio driver, helper tools and radio Mosh launcher. Homebrew and APT bring in the runtime dependencies.
Package installs are checked on Apple Silicon / macOS 26 and five Debian/Ubuntu releases. The radio path has been exercised between a Mac and Linux workstation.
goTenna is a narrow link. Discovery and startup can take time, and radio-only SSH setup remains experimental. Keep the initial test on an existing SSH connection.
Mac build records ↗