Ferrum

FerrumTerm

Alpha

A GPU terminal whose sessions live in a server, with the fterm CLI for humans and agents.

A terminal written entirely in Rust, inspired by GPU terminals and tmux. A server owns the sessions, and the GPUI window, the fterm CLI and attach are just clients.

Download LauncherInstall with Ferrum Launcher

What FerrumTerm does

The server, CLI and attach are covered by automated tests with real PTYs. The window was recently moved to GPUI.

  • Terminals live in a server

    Sessions, tabs and split panes run in a background server. Closing the window only disconnects; your programs keep running.

  • GPU window

    Tabs, splits, truecolor, wide CJK and emoji cells, scrollback and IME input, rendered with GPUI.

  • The fterm CLI

    Create sessions, run commands in new splits or tabs, send keys, capture output and wait on status, with JSON output for scripts.

  • Built for AI agents

    Programs report working, done, blocked or error status; you get notifications, and the Mac stays awake while agents work.

  • tmux-style attach

    fterm attach renders splits and a status line in any terminal, over SSH too, with a C-b prefix for the usual commands.

  • Reach it from another Mac

    Optional listeners on loopback or your Tailscale address only, protected by a 256-bit token.

Status: Alpha

FerrumTerm is in alpha. The GPUI window has been launch-tested (connects, creates a session, sizes the grid) but not yet used day to day.

Works today

  • Persistent server with sessions, tabs, splits and 10k-line scrollback
  • fterm server start, stop, status, logs and a login LaunchAgent
  • Scriptable CLI with --json and status-aware wait
  • Program status via OSC 7501 or fterm status, with notifications
  • tmux-style attach
  • Token-protected remote access over loopback or Tailscale
  • Sidebar with sessions and an Agents section (Claude Code, Codex)
  • Mouse selection and copy (⌘C)
  • Saved SSH hosts and ~/.ssh/config hosts, with fterm ssh
  • Local, remote and SOCKS port forwards run by the server
  • What's using a port, with a confirmed kill (fterm port)

Not built yet

  • Mouse reporting to programs
  • OSC 8 hyperlinks and ligatures
  • Config file, themes and search
  • Restoring sessions after the server itself restarts
  • Kitty keyboard and graphics protocols

Requirements & built with

Install
Ferrum Launcher (free, see Download)
Includes
The FerrumTerm window and the fterm CLI
Builds
macOS (Apple Silicon and Intel) and Linux x86_64
Built with
Rust, GPUI, alacritty_terminal, portable-pty, Tokio
Tested on
macOS

Anyone holding a remote-access token can run programs as you: treat it like an SSH key.