In 2016, Uber faced significant engineering challenges due to a monolithic codebase and hundreds of developers working on a single repository, resulting in slow production times and numerous incidents. To address these issues, Uber embarked on a phased approach focusing on enhancing developer velocity and experience by breaking down monorepos, developing custom CI/CD tooling, and building their compute infrastructure to improve build times. This resulted in an 80% improvement in velocity and a significant reduction in lead time for code merges. To facilitate end-to-end testing in a microservices-intensive environment, Uber introduced tools like Cerberus and DevPod, which provided ephemeral, production-like development environments, enhancing testing capabilities while controlling costs. These efforts led to an impressive increase in production changes and improved build times, ultimately elevating Uber's internal developer satisfaction. The lessons learned at Uber suggest that by focusing on metrics and improving velocity through effective tooling and methodologies, other companies can enhance their engineering productivity, even amid rising costs and competitive pressures. This experience has inspired the creation of platforms like Devzero, which aim to provide engineering teams with flexible infrastructure management while maintaining developer freedom.