If I am looking at archive docs for 2.3, e.g: http://singularity.lbl.gov/archive/docs/v2-3/user-guide Then the links on that page point at the current version (2.4) docs, e.g. the Examples->run link on the 2.3 docs is pointing to.... http://singularity.lbl.gov/docs-run This just made my head hurt a bit, but will catch out users of older versions if things have changes 2.3 -> 2.4