plash Alternatives

plash

Runs anywhere
Plash's only requirements are python3, a linux kernel (>= 3.18) and a rudimentary mount binary in $PATH. It does not need an extra daemon and can be easily run in infrastructure not meant to support containers like virtually any ci environment, embedded systems or even docker containers.

Security
Plash can be used completely unprivileged (with unionfs-fuse and newuidmap as dependencies)

Its just processes
Plash containers are processes exactly like you know them. They can be listed with ps, killed, you can filter for stderr or pipe to stdin, manage them in groups with supervisord and runit or simply access files in your home directory. Only parts of the filesystem are isolated. More isoalition could be provided by seperate tools.

Plashfiles
Plashfiles are executable build files featuring optional lightweight configuration management capabilities.