Package: nash-default-shell Version: @VERSION@ Architecture: all Maintainer: Nucleic Section: shells Priority: optional Depends: nash Description: force nash as the system default shell (NASH.md §7.1) The maintainer-script form of the locked divert block: /bin/bash and /bin/dash are dpkg-diverted to /usr/bin/{bash,dash}.real and /bin/{bash,dash,sh} point at nash, so shebangs and tools that hardcode sh/bash land in nash. Real shells stay reachable at the .real paths — nash's parse-failure fallback depends on them. Removing this package cleanly restores stock shells. dpkg-divert keeps apt upgrades of bash/dash from clobbering the links.