Amake: cached builds of top-level targets

This paper describes a software-build tool named Amake, an extension of GNU Make. Its additional features solve important problems that have, until now, only been addressed by “high-end” build tools (e.g., ClearCase and Vesta). With a typical build tool, if a top-level target must be updated, intermediate targets must be built from sources, and then combined to build the top-level target. The enhancements described here allow a top-level target to be fetched from a shared cache, without building, or even fetching its intermediate-target dependencies. Thus, a developer's workspace may need only contain sources and top-level targets. This reduces build time, reduces network traffic, and saves disk space.