Claude Code, like it's 2004 
CMSN puts Claude Code in a window that looks like an early-2000s Messenger conversation, with a contact list, display pictures, emoticons, sounds and a Nudge button. Every chat is a real Claude Code session.
Requires macOS 26 or later and Claude Code.
A contact list of chats
Each conversation is a Claude session, green while working and blinking when it needs you. Pin, rename and reorder them.
A real terminal inside
CMSN runs your own installed claude, so your subscription, settings, plugins and MCP servers all just work.
Emoticons and Nudges
Messenger's grid of 60 emoticons, sent to Claude as emoji. And yes, you can nudge Claude.
Pick up where you left off
Resume previous conversations, including Code sessions from the Claude app.
Several Claude accounts
Switch between work and personal accounts, and choose what each shares.
Pick your resolution
Draw CMSN anywhere from 640 by 480 to 1600 by 1200, like XP's Display Properties.
Commands, Model and Usage
Browse Claude Code's slash commands, switch models, and see your limits as XP progress bars, all from the toolbar.
Sounds and alerts
Messenger's sounds, a Dock badge and a bounce when Claude replies or needs approval. Set yourself to Busy for peace and quiet.
Chat with Claude Code the way you used to chat with your friends
Messenger-style chat windows for Claude Code- A contact list with every conversation
- Sounds, blinking and Dock badges when Claude needs you
Emoticons, display pictures and Nudges
One purchase, with updates included.
FAQ
Do I need a Claude subscription?
You need Claude Code installed and an account it can sign in with. CMSN runs your own claude, so it uses whatever plan or account you already use in Terminal. CMSN can also sign you in itself.
How can I download CMSN again if I bought it before?
Your receipt email from Gumroad has a link to download the app again.
If you no longer have the email, download it from your library at gumroad.com. If you never made a Gumroad account, create one with the email you bought CMSN with, sign in, and CMSN will be in your library.
Why is CMSN sold through Gumroad instead of the Mac App Store?
CMSN runs the Claude Code you've installed, in your project folders, with the tools it uses. Mac App Store apps run in a sandbox that doesn't allow that, so CMSN is signed and notarized by Apple and sold through Gumroad instead.
Does CMSN see my code or conversations?
No. Everything stays on your Mac. CMSN talks to Claude Code through a small server that only listens on your own computer, and Claude Code talks to Anthropic as it always does.
Which Macs does CMSN run on?
Any Mac with macOS 26 or later.
Is CMSN made by Microsoft or Anthropic?
No. CMSN is an independent app, not affiliated with Microsoft or Anthropic. It has its own name, artwork and sounds.