Abuild makes no specific commitments about the order in which items will be built except that no item is ever built before its dependencies are built. The exact order in which build items are built, other than that dependencies are built before items that depend on them, should be considered an implementation detail and not relied upon. When abuild is invoked in with multiple threads (using the --jobs option, as discussed in Chapter 13, Command-Line Reference), it may build multiple items in parallel. Even in this mode, abuild will never start building one build item until all of its dependencies have been built successfully.