I think you’re overlooking the beginning of this article where they specifically call out the use-case is moving towards their monorepo(s). Do you really think all of Uber’s source could be built and rebuilt continuously on one developer laptop while keeping pace with organization-wide releases? It’s one thing to build a sub module or a few modules locally, but they’re specifically talking about the efficiencies gained through caching ALL build artifacts, source code, and leveraging data locality to place an otherwise inordinate amount of compute power in the hands of developers to do as they please.