cmux
Terminal app for running and organizing multiple AI coding agent sessions, built on libghostty
HN commenters like it for running many Claude Code and Codex agent sessions at once1234, grouping terminals into per-project workspaces567, and a built-in browser and tools that agents can use.8910 The main caveats are that it is macOS-only and does not work on remote terminals11, and one user switched back to Ghostty over bugs, unreliability, and high memory and CPU usage.12
Why people recommend it
Multi-agent workflows · 3
Commenters use it to run and keep track of many Claude Code or Codex instances at once.
“Cmux was perfect for tons of ClaudeCode/Codex instances.”
“I love CMUX and some people I know who were building their own tmux setups bailed and just started using CMUX”
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“Use cmux or conductor to manage multiple instances of Claude Code”
Project workspaces · 3
Users like grouping tabs and splits into per-project workspaces with fast access to each project.
“the main reason I love cmux is how can I manage my projects into folders”
“I use cmux because I like tabbed terminals on macOS grouped by project”
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“I love CMUX and some people I know who were building their own tmux setups bailed and just started using CMUX”
tmux alternative · 3
Former tmux users say it gives session management and layouts without tmux setup or shortcuts.
“I'm currently using CMUX, and been pretty happy with it it at this time”
“I love CMUX and some people I know who were building their own tmux setups bailed and just started using CMUX”
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“I've been using cmux for a long time too but am pretty happy with it.”
Agent browser tools · 3
Its built-in browser and shell tools let agents test work without vendor lock-in.
“With cmux your agents can access the browser, spawn full shells, and you aren't locked-in to a specific vendor.”
“I love CMUX and some people I know who were building their own tmux setups bailed and just started using CMUX”
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“I use cmux browser.”
Agent notifications · 1
One user values OS-level notifications when an agent is ready, plus auto-resume.
“I'm currently using CMUX, and been pretty happy with it it at this time”
Caveats and dissent
macOS only · 1
One user notes it runs only on macOS.
“a week ago I was using cmux but its osx only and doen't work on remote terminals.”
No remote terminals · 1
It doesn't work on remote terminals, which led one user to switch away.
“a week ago I was using cmux but its osx only and doen't work on remote terminals.”
Stability and resources · 1
One user reported unreliability, bugs, and high memory and CPU usage.
“had to switch back to Ghostty due to its unreliability, high memory and CPU usage and a bunch of bugs”
Setup needed · 1
Agents need an updated instruction file to know they can use cmux's tools.
“With cmux your agents can access the browser, spawn full shells, and you aren't locked-in to a specific vendor.”
Often compared with
Who recommends it in their own words
Threads where it came up
- Herdr is joining Y Combinator. The runtime stays open 2 mentions
- Herdr: One terminal to rule them all 2 mentions
- Tmux and Claude Code: Sessions, Send-Keys, and the Ceiling 1 mention
- Pi 1.0 1 mention
- Show HN: Saggar, a Mac terminal that keeps sessions and your attention organized 1 mention
- Why does Opus 5 feel worse to work with? 1 mention
Also written as Cmux, CMUX. Data: cmux.json. Quotes are verbatim; the verdict and theme labels are written by a model from these comments, and every clause links to its sources.
All comments 21
“I love CMUX and some people I know who were building their own tmux setups bailed and just started using CMUX”
“There are other GUI tools like Juggler that are quite popular, like cmux”
“I use cmux browser.”
“Cmux, Sol and omp are my tools for now.”
“I really like what herdr, cmux and others are doing in this space”
“open it in cmux (another agentic terminal)”
“the main reason I love cmux is how can I manage my projects into folders”
“I use cmux because I like tabbed terminals on macOS grouped by project”
“I'm currently using CMUX, and been pretty happy with it it at this time”
“cmux is using libghostty too”
“With cmux your agents can access the browser, spawn full shells, and you aren't locked-in to a specific vendor.”
“I built a multi-agent alternative with Stream Deck and cmux/orca”
“I use cmux.”
“I've been using cmux for a long time too but am pretty happy with it.”
“Cmux does tabs in panes AND panes in tabs.”
“I use it to quickly open projects in cmux”
“Use cmux or conductor to manage multiple instances of Claude Code”
“Cmux was perfect for tons of ClaudeCode/Codex instances.”
“a week ago I was using cmux but its osx only and doen't work on remote terminals.”
“I have been using cmux over the last few weeks”
“had to switch back to Ghostty due to its unreliability, high memory and CPU usage and a bunch of bugs”