What is Herdr and how does it compare to tmux?

Herdr is an open-source terminal multiplexer built for AI coding agents: one Rust binary, Apache-2.0, v0.9.5 released October 14, 2026, about 49,500 GitHub stars on November 9, 2026. Like tmux it keeps terminals running after you detach, but it also marks every pane as working, blocked or idle, lists agents across local and SSH machines in one window, and exposes a socket API so agents can spawn panes and wait on each other. tmux (3.8, September 9, 2026) is more mature and universal but knows nothing about agents.

Which terminal multiplexer is best for running several coding agents?

As of November 9, 2026: Herdr if you run several CLI agents and want to see at a glance which one is stuck; cmux if you are on a Mac and want a native terminal app with notification rings and a built-in browser; Zellij if you want a friendlier general-purpose multiplexer with floating panes, WebAssembly plugins and a web client; tmux if you need something installed on every server and scriptable for decades.

Yes. Herdr is licensed under Apache 2.0, with no paid tier listed in its repository. It installs with a curl script, Homebrew (brew install herdr), mise or, in beta, a PowerShell script on Windows. It runs inside whatever terminal you already use.

Do I need a multiplexer or a desktop app like Orca?

A multiplexer keeps agents running in terminals you can detach from and reach over SSH. A desktop agent environment such as Orca (MIT, about 119,700 GitHub stars on November 9, 2026) adds git worktree management, diffs and a mobile companion around the same CLI agents. Many developers use both: worktrees from a desktop app or CLI, agents inside a multiplexer on a remote box.

Quick Answer

Herdr vs tmux vs Zellij vs cmux for AI Coding Agents

Published: November 9, 2026

The short answer

Herdr is tmux rebuilt around coding agents: it tells you which agent is blocked and lets agents drive the terminal themselves. As of November 9, 2026:

Herdr — best for running several CLI agents (Claude Code, Codex, Cursor CLI, OpenCode, Grok and others) across local and remote machines. Free, Apache-2.0.
cmux — best on a Mac if you want a native, Ghostty-based terminal app with agent notifications, vertical tabs and an in-app browser. Free, GPL-3.0-or-later.
Zellij — best general-purpose modern multiplexer: floating and stacked panes, WebAssembly plugins, built-in web client. Free, MIT.
tmux — best when it must already be on every server and scripts must work for years. Free, ISC.

The comparison

Versions and star counts from GitHub on November 9, 2026.

	Herdr	cmux	Zellij	tmux
Latest release	v0.9.5 (Oct 14, 2026)	v0.65.2.2 (Oct 27, 2026)	v0.45.1 (Aug 28, 2026)	3.8 (Sep 9, 2026)
GitHub stars	~49,500	~28,700	~36,000	~50,200
Licence	Apache-2.0	GPL-3.0-or-later (server component excluded)	MIT	ISC
Platforms	Any terminal; macOS, Linux, Windows (beta)	macOS app	Linux, macOS	Unix-like systems
Knows agent state	Yes: working / blocked / idle per pane	Notification rings when an agent needs attention	No (plugins can add it)	No
Persistence	Background server; restores layout and can resume supported agent sessions after a restart	App sessions	Session resurrection	Detach/attach
Remote machines	Saved SSH machines in one window, combined agent list	`cmux ssh` workspaces, browser routed through the remote	Web client	Run on the server, attach over SSH
Agent-facing API	CLI + socket API: spawn panes, prompt other agents, wait until one is blocked	Scriptable browser API, `cmux claude-teams`	Plugin system	Mature command interface

Herdr — the agent-native multiplexer

Herdr runs as a background server, so closing the client or losing SSH does not stop your agents. After a server or machine restart it restores the saved layout and can resume supported agent sessions, though the original processes do not survive. Its headline feature is state detection: every pane is marked working, blocked or idle, so when one of six agents stops to ask a question you see it immediately. Agents can use the socket API to spawn panes, send each other prompts and wait until another agent is genuinely blocked, which makes simple multi-agent pipelines possible without a framework. Herdr does not wrap the agents; it owns their terminals. Plugins and both tmux-style prefix keys and mouse control are built in.

Pick it if you live in the terminal and run three or more agents at once. Our hands-on notes are in the Herdr review.

cmux — the native Mac option

cmux is a full terminal app rather than a multiplexer inside your terminal. Panes get a blue ring and tabs light up when an agent needs attention; a notification panel jumps to the latest unread one. The sidebar shows each workspace’s git branch, linked PR status, working directory and listening ports. It adds a split-pane browser with a scriptable API, cmux ssh workspaces for remote machines, and cmux claude-teams, which runs Claude Code’s teammate mode as native splits.

Pick it if you are on macOS and prefer a polished app to a TUI. Skip it if you need Linux or Windows.

Zellij — the friendlier general multiplexer

Zellij is not agent-specific, but it is the easiest modern multiplexer to learn: sensible defaults, layouts, floating and stacked panes, multiplayer sessions, plugins in any language that compiles to WebAssembly, and a built-in web client that makes a local terminal optional.

Pick it if you want one tool for agents and everything else, and are willing to add agent awareness through layouts or plugins.

tmux — still the universal baseline

tmux 3.8 shipped September 9, 2026, and it remains the multiplexer already installed on almost every server. It has no idea what an agent is, but every agent works inside it, and years of scripts and muscle memory carry over.

Pick it if you manage fleets of servers or need maximum stability. Plenty of agent tools build on it.

Orca — a desktop “agent development environment” that runs Claude Code, Codex and other CLIs in their own git worktrees, with a mobile companion; MIT, v1.4.254 on November 8, 2026. See Conductor alternatives.
Claude Squad — a free terminal manager for several agents (AGPL-3.0, v1.0.20, August 20, 2026).
For isolating each agent’s changes, combine any of these with git worktrees.

How to choose

How many agents at once? One or two: whatever you already use. Three or more: Herdr or cmux, because spotting the blocked agent is the bottleneck.
Which OS? macOS only: cmux is an option. Linux servers: Herdr, Zellij or tmux.
Remote boxes? Herdr’s combined agent list across SSH machines is the strongest; tmux is the safest.
Licence matters? Apache-2.0 (Herdr), MIT (Zellij) and ISC (tmux) are permissive; cmux is GPL.

Last verified: November 9, 2026.