As applications built on Rails get larger and larger, and more and more engineers work in the same monolith, our community needs to think more about what sort of tooling and architectural changes will help us continue to scale. This talk shares ideas around a toolchain, and more importantly, the social and cultural programs needed to support that toolchain, that can be used to help engineers in an ever-growing Rails codebase continue to have high velocity, manage their complexity, and claim ownership over their own business subdomains.