Coming from Linux land, I assumed that pkgin is some sort of higher-level frontend for pkg_add et al, something like what apt is to dpkg or yum / dnf to rpm . But pkg_add appears to handle installation from network, dependencies, as well as automatic updates (the things that on Linux would be the responsibility of the front-ends rather than the underlying package tool), so now the roles of pkgin and (what I gather are the more traditional) pkg_...
Originally asked by jaymmer - Reinstate Monica on Stack Exchange (unix) (CC BY-SA 4.0).