Keeping main green in a monorepo

The text discusses the challenges and solutions related to maintaining a stable "main" branch in a software development environment, emphasizing the problems caused by "red" or failing Continuous Integration (CI) statuses. It critiques the use of merge queues as a solution due to their complexity, increased costs, and inability to address all underlying issues such as flaky tests or outdated code dependencies. Instead, it proposes a combined strategy of improving test reliability, implementing a freshness policy for PR statuses, and having a "Build Cop" on-call to manage immediate issues. The text suggests using a "Latest Known Green" reference to ensure developers work from a stable code base, reducing the likelihood of integrating broken changes. Additionally, it highlights the benefits of having a dedicated individual to manage the main branch's stability across larger repositories, and mentions Aspect's integration of these workflows for Bazel users.