Docker and Guix are mechanisms for building and running isolated “containers” of software. They eliminate “works on my machine” problems when collaborating on code with co-workers; enable running and managing apps side-by-side in isolated containers to get better compute density; and can be used to build agile, updateable software delivery pipelines. They offer package management features, support transactional upgrades and roll-backs, and per-user profiles. While Docker is better known, it requires privileged (root) management. Guix works without need for root privilege.