how we compare

Docker does more. We do one thing it can't.

Docker is the obvious choice for most teams, and this page says so. It runs on more computers, has more around it, and most people already use it. There is one thing it doesn't do — and that's the reason kosa8 exists.

Can it…	Docker Sandboxes	kosa8
Runs each assistant in its own sealed machine	Yes	Yes
Control which folders and websites it can reach	Yes	Yes
Company-wide rules and an audit trail	Yes	Yes
Ready for Claude Code, Codex, Gemini, Copilot	Yes	Yes, plus Cursor and AZMX
Save a machine mid-task and bring it back	—	Yes
Copy a running machine several ways at once	—	Yes
Try several fixes side by side, automatically	—	Yes
Move a saved machine to another computer	No — it's discarded at the end	Yes
Works on Windows and Linux	Yes	Mac only (Apple Silicon)
App store of ready-made images	Yes	No
Desktop app with a window	Yes	Command line only

Based on Docker's own website and documentation, July 2026. We publish no speed comparisons because we haven't measured Docker.

Which one should you use?

Use Docker if

You're on Windows or Linux
You want a desktop app, not a terminal
You need ready-made secure images
Your company already runs Docker everywhere

Use kosa8 if

Your setup is slow and you retry a lot
You want several fixes tried at once
You need to undo what an assistant did
You want to hand a working machine to a colleague

The honest version

Docker's sandboxes are designed to be thrown away when you're done. Their own documentation says so.
Other tools that do save something usually save only the files. kosa8 saves the running programs too, so a copy carries on mid-task.
If you never need to go back to an earlier moment, or try things side by side, you don't need kosa8.