Headless multiplexer
Unterm vs rmux
Both let programs drive a terminal. rmux gives your code a library; Unterm gives your agent a protocol — and gives you a window to watch it all.
rmux (public preview, v0.2) is a Rust terminal multiplexer in the tmux lineage: a daemon that keeps sessions alive across disconnects, ~90 tmux-compatible commands, native Windows ConPTY, and a typed async SDK with structured pane snapshots and Playwright-style waits. It has no GUI — it is infrastructure for code that uses terminals, and it's genuinely good at that.
| Feature | Unterm | rmux |
|---|---|---|
| MCP-controllable from outside | ✓ | ✗ (SDK only) |
| Scriptable CLI for every action | ✓ | ✓ tmux-compat |
| Built-in AI coding-agent launcher | ✓ ×7 | ✗ |
| Agents auto-wire to the terminal's MCP | ✓ | ✗ |
| Agent Cockpit (Inbox · fleets · review) | ✓ | ✗ |
| Identity profiles (creds per window) | ✓ | ✗ |
| Multi-instance orchestration | ✓ | ~ sessions |
| Session recording → markdown | ✓ md | ~ snapshots |
| Screenshot + file upload from MCP | ✓ | ✗ |
| Right-click = copy / paste gesture | ✓ gesture | — |
| Built-in proxy management | ✓ | ✗ |
| Local-first, no cloud | ✓ | ✓ |
| AI inside the terminal | ✓ agent-driven | ✗ |
| GPU rendering | ✓ | — (no GUI) |
| macOS + Linux + Windows | ✓ | ✓ |
| Open-source client | ✓ MIT | ✓ MIT/Apache |
| 9-language native UI | ✓ ×9 | en |
| Price | $0 | $0 |
✓ yes · ✗ no · ~ partial · ×N count. The ✗ by design on "AI inside" is the whole thesis: Unterm keeps the AI outside and exposes the terminal as the surface it grips.
Warum Teams sich für Unterm entscheiden
- ✓ MCP, not an SDK. rmux automation means writing and shipping code against its Rust SDK. Unterm exposes 99 MCP methods — Claude Code, Codex, Gemini CLI, or any MCP client drives the real terminal with zero integration code, auto-discovered on first launch by
setup-ai. - ✓ The other direction too. rmux is one-way: code drives terminal. Unterm also watches the agents running inside it — live per-pane state, the waiting-first Inbox, worktree fleets with verification-gated review. The terminal is a cockpit, not just a target.
- ✓ A terminal humans use. Unterm is the GPU window you work in all day: right-click copy/paste gesture, identity profiles, 9 UI languages, session recording to redacted markdown. rmux has no rendering surface at all — pairing it with a terminal app is on you.
Wo rmux stärker ist
rmux's session persistence is real tmux-grade: SSH drops and your agent's shell keeps running, reattachable from anywhere. Its typed snapshots and wait_for_text locators are finer-grained than text matching, and a headless daemon fits CI pipelines where no GUI can exist. It's also embeddable in Ratatui apps.
Fazit
Building a system where code owns terminal sessions in CI or on servers? rmux is a strong primitive. Working alongside AI agents at a desk, in a terminal you also live in? That's Unterm — protocol-native for agents, cockpit-native for you.
MIT-lizenziert · macOS / Linux / Windows · kein Konto, kein Login.