Agentastic vs cmux
cmux and Agentastic are both native Mac apps that render terminals with Ghostty's engine, and both are built for people who run many coding agents. cmux is the terminal: vertical tabs, splits, notification rings, a scriptable browser, and a socket API, free and open source under GPL-3.0. Agentastic is the IDE around the terminals: it creates a worktree, container, SSH host, or cloud VM for every task, and adds an editor, review passes, pull requests, and issue intake.
Who should choose each option#
Agentastic
Choose Agentastic if you want the whole loop in one app: a worktree per agent, an editor, AI review passes, and cloud or SSH agents on your own accounts.
cmux
Choose cmux if you want a fast, scriptable, open-source terminal for agents and are happy to wire up worktrees and review yourself.
Feature comparison#
| Feature | Agentastic | cmux |
|---|---|---|
| Form factor | Native macOS IDE (Swift) | Native macOS terminal (Swift) |
| Platforms | macOS 14+ | macOS; a separate nightly Linux x64 build |
| Terminal | GPU-accelerated Ghostty | GPU-accelerated libghostty; reads your Ghostty config |
| Supported agents | 55 built-in definitions plus any terminal agent | Any CLI agent |
| Worktree per agent | Built in | Script it with a custom command |
| Built-in editor | Yes, with LSP, search, and source control | No; it is a terminal |
| Built-in browser | Agents drive it with the dev browser CLI; Design Mode; Share Live Preview | Scriptable browser panes (navigate, snapshot, click, read console and network) |
| Review and pull requests | Review passes by Claude, Codex, CodeRabbit, or Greptile; review, watch CI, and merge GitHub PRs in the app | Sidebar shows git branch, ports, and notifications |
| Needs-attention alerts | Pane rings, an inbox, and macOS notifications | Pane rings, badges, and macOS notifications |
| Remote agents | Any SSH host | SSH workspaces and remote tmux sessions (beta) |
| Cloud agents | Free: Modal, Fly.io, or Vercel Sandbox on your own account | cmux Cloud VMs, from $50/mo |
| Container isolation | Docker or Apple Container per task | No local container mode in its docs |
| Issue intake | Linear, Sentry, Slack, and schedules start agent runs | Build it on the socket API |
| Automation | The dev CLI | The cmux CLI and a Unix socket API |
| Mobile | iPhone app in public beta on TestFlight (iOS 18+), free | iOS app on TestFlight, with paid plans |
| License | Free, closed source | Open source (GPL-3.0-or-later) |
Pricing#
Agentastic
Free. Cloud agents, remote SSH, Linear and Sentry intake, browser automation, review passes, and the iPhone beta are all in the free app. Bring your own agent subscriptions.
cmux
The terminal and local agents are free and open source. Cloud VMs and the iOS app come with Pro ($50/mo), Max ($200/mo), or Team ($60/user/mo); SSO and self-hosted execution are Enterprise.
Using them together#
cmux is a terminal and Agentastic is an IDE, so they overlap more than they stack. Both run the same agent CLIs on ordinary git branches, so trying one does not lock you out of the other.
Frequently asked questions#
Is cmux a tmux wrapper?
No. Despite the name, cmux is a native Swift and AppKit terminal built on libghostty, the rendering library behind Ghostty. It can attach to remote tmux sessions, but it is not a tmux front end. Agentastic also renders its terminals with Ghostty.
cmux vs Ghostty: what is the difference?
Ghostty is a standalone terminal. cmux is a separate app that uses libghostty for rendering and reads your Ghostty config, then adds vertical tabs, notification rings, a browser, and a socket API for agents (cmux). Agentastic also uses Ghostty for its terminals.
Does cmux create a git worktree for each agent?
Not out of the box. cmux gives you workspaces, splits, and custom commands, and its docs show a custom command that creates a worktree and starts agents in it. Agentastic makes the worktree part of launching an agent, then adds a diff view, review passes, and merge on top.
Does cmux run on Windows or Linux?
The cmux terminal is a macOS app; there is also a nightly Linux x64 build that pairs Chromium tabs with terminal surfaces (cmux for Linux), and no Windows version. Agentastic is macOS only, and both can drive agents on Linux machines over SSH.
Does cmux have an iPhone app?
Yes, an iOS app on TestFlight that mirrors your Mac terminals and comes with cmux's paid plans (cmux iOS). Agentastic's iPhone app is a free public beta on TestFlight that adds diff review, pull request merges, and new tasks on top of watching agents.
What does cmux charge for?
The terminal and local agents are free. Cloud VMs, which are persistent Linux machines in cmux's cloud, start with Pro at $50 a month, and the iOS app comes with paid plans (pricing). Agentastic runs cloud agents on your own Modal, Fly.io, or Vercel Sandbox account, and the app is free.
Which one is better for a single agent?
For one agent in one terminal, cmux is the simpler tool: the terminal is the whole product. Agentastic earns its place once several agents work at once and you need isolation, review, and a place to merge.
Further reading#
terminals and workspaces for coding agents
Ghostty, cmux, Warp, and Agentastic compared
what a worktree-per-agent setup has to handle
the wider roundup this comparison sits inside
See also#
Conductor is a chat-first Mac app that gives each agent its own worktree. cmux is an open-source, Ghostty-based terminal for any CLI agent. Compare the two.
Warp is an open-source agentic terminal with its own agent and editor. Agentastic is a native Mac workspace that runs many CLI agents in isolated worktrees.
Both run coding agents in parallel git worktrees. Agentastic is native Swift with containers and cloud agents; Orca is open-source Electron for every OS.
Both run coding agents in parallel git worktrees on macOS. Agentastic is native Swift with any CLI agent and free cloud runs; Conductor is chat-first.
Both run CLI coding agents in parallel git worktrees. Agentastic is native Swift and free for cloud, SSH, and Linear; Superset is Electron, with those on Pro.