
cmux is the open-source terminal built for coding agents. Built by @lawrencecchen @austinywang
San Francisco, California
Joined June 2024
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cmux retweeted
cmux is coming to stanford!
Iโm excited to finally announce the newest edition my Stanford course ๐ง๐ต๐ฒ ๐ ๐ผ๐ฑ๐ฒ๐ฟ๐ป ๐ฆ๐ผ๐ณ๐๐๐ฎ๐ฟ๐ฒ ๐๐ฒ๐๐ฒ๐น๐ผ๐ฝ๐ฒ๐ฟ. It has been 9 months in the making.
Last November, with the release of Claude Opus 4.5, coding agents experienced a step function improvement in capability. We all felt it. The LLMs were more powerful, could reason for longer, solve harder tasks.
This yearโs iteration of my course reflects the 2026 metamorphosis of software engineering.
My core belief is simple: AI-native developers of the LLM era are going to become the most important members of any software organization. I have designed my course to train this next generation of engineers.
๐ช๐ต๐ฎ๐โ๐ ๐ฑ๐ถ๐ณ๐ณ๐ฒ๐ฟ๐ฒ๐ป๐ ๐๐ต๐ถ๐ ๐๐ถ๐บ๐ฒ ๐ฎ๐ฟ๐ผ๐๐ป๐ฑ
First, 85% of my Fall 2025 class material is being thrown out.ย The Fall 2026 syllabus reflects the core capabilities AI-native engineers must have: agent skills, advanced context engineering, MCP portals, agent-ready codebase principles, agentic code review, security, parallelizing background agents, software factories, and more.
Second, I am going to teach my students how to have software taste. Every student will be required to ship pull requests to production-grade, real-world codebases. The course is collaborating with the top open-source AI repos who will offer support and mentorship to students on how to meaningfully contribute to their projects.
This has never been done before in any university course so I am incredibly grateful to our OSS Partners:ย @browserbase, @HeyGen, @CopilotKit, @semgrep, @OpenHandsDev, @milvusio, @marimo_io, Pi, @crewAIInc, @warpdotdev, @vercel, @cmux, @arizeai, @UnslothAI, and @anyscalecompute.
๐ช๐ต๐ฎ๐โ๐ ๐๐๐ฎ๐๐ถ๐ป๐ด ๐๐ต๐ฒ ๐๐ฎ๐บ๐ฒ
Iโm fortunate to again have AI software engineering leaders and founders as guest speakers to share their learnings from building top coding agent products. Thank you to @leerob from @cursor_ai, @bcherny of @claudeai code, @EnoReyes of @FactoryAI, @silasalberti of @cognition, @0xine of @semgrep, Rajesh Bhatia of @Cloudflare , @amasad of @Replit, and @eladgil.
All resources will be available online. All classes will be available to the public.
9/22 on Stanford campus. See you in class.ย
themodernsoftware.dev/
cmux will be an open-source partner for this course at Stanford. See you in class!
Iโm excited to finally announce the newest edition my Stanford course ๐ง๐ต๐ฒ ๐ ๐ผ๐ฑ๐ฒ๐ฟ๐ป ๐ฆ๐ผ๐ณ๐๐๐ฎ๐ฟ๐ฒ ๐๐ฒ๐๐ฒ๐น๐ผ๐ฝ๐ฒ๐ฟ. It has been 9 months in the making.
Last November, with the release of Claude Opus 4.5, coding agents experienced a step function improvement in capability. We all felt it. The LLMs were more powerful, could reason for longer, solve harder tasks.
This yearโs iteration of my course reflects the 2026 metamorphosis of software engineering.
My core belief is simple: AI-native developers of the LLM era are going to become the most important members of any software organization. I have designed my course to train this next generation of engineers.
๐ช๐ต๐ฎ๐โ๐ ๐ฑ๐ถ๐ณ๐ณ๐ฒ๐ฟ๐ฒ๐ป๐ ๐๐ต๐ถ๐ ๐๐ถ๐บ๐ฒ ๐ฎ๐ฟ๐ผ๐๐ป๐ฑ
First, 85% of my Fall 2025 class material is being thrown out.ย The Fall 2026 syllabus reflects the core capabilities AI-native engineers must have: agent skills, advanced context engineering, MCP portals, agent-ready codebase principles, agentic code review, security, parallelizing background agents, software factories, and more.
Second, I am going to teach my students how to have software taste. Every student will be required to ship pull requests to production-grade, real-world codebases. The course is collaborating with the top open-source AI repos who will offer support and mentorship to students on how to meaningfully contribute to their projects.
This has never been done before in any university course so I am incredibly grateful to our OSS Partners:ย @browserbase, @HeyGen, @CopilotKit, @semgrep, @OpenHandsDev, @milvusio, @marimo_io, Pi, @crewAIInc, @warpdotdev, @vercel, @cmux, @arizeai, @UnslothAI, and @anyscalecompute.
๐ช๐ต๐ฎ๐โ๐ ๐๐๐ฎ๐๐ถ๐ป๐ด ๐๐ต๐ฒ ๐๐ฎ๐บ๐ฒ
Iโm fortunate to again have AI software engineering leaders and founders as guest speakers to share their learnings from building top coding agent products. Thank you to @leerob from @cursor_ai, @bcherny of @claudeai code, @EnoReyes of @FactoryAI, @silasalberti of @cognition, @0xine of @semgrep, Rajesh Bhatia of @Cloudflare , @amasad of @Replit, and @eladgil.
All resources will be available online. All classes will be available to the public.
9/22 on Stanford campus. See you in class.ย
themodernsoftware.dev/
cmux retweeted
cmux (@manaflowai) iOS app beta is awesome
cmux retweeted
cmux iOS has an interactive simulator pane that streams iOS simulators from your Mac!
This Post is from an account that no longer exists. Learn more
cmux retweeted
I was complaining about cmux performance, but after visiting @manaflowai office, they helped me to set up it properly. Now I understand the beauty of cmux:
you can make tmux sessions, but with GUI, and auto restore
That is a game changer, I can't live without this anymore
cmux retweeted
I demoed at a devtools meetup and the devs demoing were using:
Ghostty - 10
cmux - 3
VSCode/Cursor - 3
Codex app - 1
Other - 4
๐ค
cmux retweeted
Demoed our cmux iOS app in beta at @WorkOS! Found some cmux users here too ๐
cmux retweeted
My most used cmux shortcuts
โ+Shift+P, then:
fork tab -> Fork Conversation to New Tab
fork right -> Fork Conversation to the Right
pin -> Pin Workspace
top -> Move to Top
โ+Shift+U -> Focus + flash latest unread pane
โ+Shift+L -> New browser tab
โ+L -> Focus browser omnibar, else new browser tab
โ+Shift+Enter -> Maximize pane
โ+Control+W -> Close workspace
โ+W -> Close tab
โ+Shift+M -> Toggle Vim mode (then "gg" to get to top and "shift+g" to get back to bottom"
โ+Shift+R -> Rename workspace
โ+R -> Rename tab
โ+D -> Split right
โ+Control+= -> Equalize splits
โ+N -> New workspace
โ+T -> New tab
What else should we add?
cmux retweeted
Iโm building a new thing on cmux similar to symphony and its been helping me get through 1.6k issues on GitHubโฆ
Requires some setup to get your agents to write good code and close the loop but knowing when it is fully confident vs not is super keyโฆ
cmux retweeted
What if cmux's sidebar had multiple columns?
Left-most column is for machines (this MacBook, Mac Mini, cloud VM), right column is workspaces in that machine.
Maybe another column for agents in that workspace?
cmux retweeted
This is my exact workflow btw
I used 367 billion tokens in the last 30 days by multitasking with cmux
My peak per-day token usage is 37 billion tokens on GPT 5.6 Sol
Would have cost $85k over API but we only paid $7.4k (37 ChatGPT Pro 20x accounts + tons of tibo resets... and this is only my usage, since subrouter lets my cofounder share usage with me too (and CodexBar only counts local token usage))
cmux retweeted
Quick video on how I used 367 billion tokens in the last 30 days by multitasking with cmux
My peak per-day token usage is 37 billion tokens on GPT 5.6 Sol
My workflow is pretty simple. The 80/20 is that I press Cmd+Shift+U whenever Codex notifies me, and I review the cmux dev build/artifact/bug fix, and respond. And then Cmd+Shift+U and repeat...
If there's ever a point in time where there's no more notifications that I need to Cmd+Shift+U to, I start a new workspace with a new task.
I don't use fancy harnesses (just vanilla Claude Code/Codex), I don't do fancy agent orchestration either (I only use the built in subagents from Codex/Claude Code), I don't use /loop, and I barely use /goal.
This would have cost $85k over API but we only paid $7.4k (37 ChatGPT Pro 20x accounts + tons of tibo resets... and this is only my usage, since subrouter lets my cofounder share usage with me too (and CodexBar only counts local token usage))
xitter.cf/lawrencecchen/status/2โฆ
I used 367 billion tokens in the last 30 days by multitasking with cmux
My peak per-day token usage is 37 billion tokens on GPT 5.6 Sol
Would have cost $85k over API but we only paid $7.4k (37 ChatGPT Pro 20x accounts + tons of tibo resets... and this is only my usage, since subrouter lets my cofounder share usage with me too (and CodexBar only counts local token usage))
















