The speaker discusses the merging process for the Rust compiler in detail. Pull requests are assigned reviewers and tags to ensure the right people are involved. The approval process includes checks for performance impact and breaking changes, and the CI must pass before anything can be merged. The speaker also explains the build queue and the different levels of testing, including compiling tests, unit tests, and tool tests. The Rust team has a tier policy for platforms that are tested, with tier one being the most fully tested. Additionally, the speaker talks about how the team freezes the build queue when making a new release and how they maintain performance metrics and look for potential regressions. The talk ends with tips for potential new contributors.