try lets you run a command and inspect its effects before changing your live system. try uses Linux’s namespaces (via unshare) and the overlayfs union filesystem.
Please note that try is a prototype and not a full sandbox, and should not be used to execute commands that you don’t already trust on your system, (i.e. devices in /dev are mounted in the sandbox, and network calls are all allowed.) Please do not attempt any commands that will remove everything in /dev or write zeros to your disks.
Very interesting! This feels like something that should have always existed.