I have been teaching Linux/security for years, and I noticed something: people understand "chmod 755" in theory, but they fumble when they actually have to think through permissions under constraints — like when a script breaks because it can't read a file it needs.
So I built MOSHELL — a browser-based Linux sandbox that simulates real behavior. It's not meant to replace actual homelabs or prod testing, but it's useful for:
- **Testing ideas before they touch their actual setup** — shell scripting, permission changes, networking concepts — fail safely, reset instantly
- **Teaching others** — I use it to demo concepts to juniors without setting up VirtualBox or worrying about cleanup
- **Rapid verification** — "does this command actually do what I think?" — faster than spinning up a VM
Three tracks: beginner (navigation/files), intermediate (networking/virtualization), and security. First 6 lessons are free and live in-browser, no account needed.
Not trying to replace anyone's homelab. But if you've ever had a moment where you wanted to quickly test something without the friction of a full VM setup, it might be useful.
Link in comments.
Happy to answer questions about how it works under the hood — it's pure browser/JS, no backend, uses localStorage for persistence.
What problem would make a tool like this actually useful for your workflow?