Manage your own packages build on a dedicated build system.

The build system does the update of the ports tree,
moving old packages out of the way, fetch and rebuild
the packages you need. Its ports tree with packages
is served to the production systems and desktops.

On a system you can update installed ports with
the clean build packages from the build system.

WWW: https://people.freebsd.org/~dinoex/batch/README.txt