When abuild builds an item, it creates an output directory under that item's directory for every platform on which that item is built. The output directory is of the form abuild-platform-name. Abuild itself and all abuild-supplied rules create files only inside of abuild output directories. ^[12]

When abuild invokes a backend to perform the actual compilation steps, it always does so from an output directory. This is true even for platform-independent build items. In this way, even temporary files created by compilers or other build systems will not appear in the build item's local directory. This makes it possible to build a specific item for multiple platforms in parallel without having to be concerned about the separate builds overwriting each other's files.