The source code for this package is maintained in git. The primary upstream branch is here: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git/secnet.git/ Upstream releases are announced here: https://www.chiark.greenend.org.uk/mailman/listinfo/sgo-software-announce There is no distinction between the upstream and Debian branches at this time. We don't maintain a Debian delta (patches), nor Debian revision numbers. Some items are included using git-subtree, notably subdirmk: This designed to be "git-subtree"'d into one's package. That is the way the upstream package uses it. It would be possible to make it a separate package and build-depend on it, at the cost of some additional work. The upside would be a very small amount of disk space saving, and largely theoretical saving of work in case of a need to do a security update for subdirmk (which seems unlikely to be critical since it's build system software which is designed to execute its input) - and that all only in the case where a second package in Debian uses subdirmk. We are deferring this work until subdirmk becomes more widely used.