The evolution of monorepos and polyrepos is a story of growth, challenges, and the quest for efficiency and collaboration. As companies transition from a small team to a large organization, they often start with a monorepo but eventually switch to a polyrepo setup due to scalability issues. However, as they grow further, many companies return to a monorepo setup to standardize their internal processes and improve code quality. The journey from a monorepo to a polyrepo and back again is not without its challenges, but the benefits of a well-managed monorepo setup can be significant. To overcome the difficulties of transitioning to a monorepo at scale, companies must carefully plan the process, address concerns about code ownership and access control, and use modern tools such as automated build systems and access control mechanisms.