There is no actual magic(*). Most of everything you have access is built using documented procedures.
- building base and xenocara follows release(8) - package sets are built using dpb(1) in most cases. * Sometimes, the snaps may contain supplementary patches that have not yet been committed. Sometimes, building the release may be "fun", there is a chapter of the faq which tries to document the fun... (building ports involve yet more fun, especially since dpb is parallel, so when things go wrong, they tend to go wrong in 20 places *at the same time* before you even get to figure out what went wrong) The whole process requires dedication, and quite some time. For comparison, a modern machine may build source in less than an hour. A similar cluster of 3 machines will take roughly fifteen hours to build a full set of packages (I'm talking *fast* amd64 there). This is one major explanation why sometimes, packages and src are not in synch. In general, unless you know what you're doing, it's best to use binary snapshots (base and package). You can try building on your own, but if things break, don't expect any kind of beginner-level hand-holding. It *is* definitely possible to learn how to build your own system, though it is definitely not the faint of heart.
