639·Shell Alpha · looking for testers
639 Shell / Docs

Getting started

639 Shell is a cloud for agents: Linux machines that you and your AI agents create, run and put online, from a terminal, over MCP or through the API. A machine is ready in seconds (see Benchmarks), sleeps when nobody is using it and wakes right where it left off. Compute is billed per second while a machine is awake; its disk is billed all the time.

Sign up

639 Shell is invite-only for now.

  1. Run ssh shell.639cloud.com and enter your email. Not invited yet? That records a request, and we email you when you're approved, with an approval code.
  2. Run ssh shell.639cloud.com again with the same email. You get a sign-in link and a QR code. No SSH key yet? It tells you how to make one (ssh-keygen -t ed25519).
  3. Open the link (or scan it). Check the key fingerprint it shows is the terminal in front of you.
  4. Continue with Google, or use your approval code (from the approval email).
  5. The page shows a short code. Type it into your terminal: that confirms it's really you at that terminal. Never give this code to anyone.
  6. Fill in your profile and accept the terms. Back in the terminal, the app opens by itself. Next time, ssh shell.639cloud.com just logs in.

Another computer: do the same from it, signing in the same way (the same Google account, or a new approval code from us), and type the page's code in that computer's terminal. Then both keys see the same machines.

Questions or problems? Send feedback in the app, or email micah@639cloud.com.

Your first machine

ssh -t shell.639cloud.com

Choose New machine, pick a size and an image, then Open shell. You are root. Type exit to come back to the app.

Or skip the app entirely:

ssh -t ubuntu-1@shell.639cloud.com          # a root shell on ubuntu-1 (wakes it)
ssh ubuntu-1@shell.639cloud.com 'uname -a'  # one command, output streamed

Getting around the app

Arrows or j/k move, Enter opens, Esc or q goes back. Press : for the command line and / to search. These docs are under Docs; press o there for a link to read them in your browser.

What the login name does

Login Opens
a machine name (ubuntu-1@) that machine: a root shell, a command, or scp/sftp
mcp@ the MCP server for AI agents
vpc@, ip@, keys@ one-shot commands for private networks, public IPs and API keys
export@ your machines as an SSH config or JSON
docs@ these docs as Markdown
legal@ the terms of service, privacy policy and abuse contact
anything else the app

The app and interactive shells need a terminal: use ssh -t.

Save these docs

ssh docs@shell.639cloud.com                          # list the pages
ssh docs@shell.639cloud.com machines > machines.md   # save one
ssh docs@shell.639cloud.com all > 639-shell-docs.md  # all of them, in one file

This page as Markdown: /docs/getting-started.md