Faced with the limitations of CircleCI, such as the inability to run UI tests on physical devices and the costliness of running lengthy internal testing tools, a team decided to establish its own continuous integration (CI) infrastructure. They opted for Veertu's Anka, a virtualization technology for macOS that allows builds to run in isolated environments, akin to Docker containers, despite Docker's lack of support for macOS containers. By using tools like HashiCorp's Packer to automate virtual machine creation and Buildkite for managing build pipelines, the team constructed a scalable and flexible CI system that can run multiple pipeline steps simultaneously across various machines. This setup allows for greater control, reduced flakiness, and the capacity to incorporate physical devices into testing, addressing the team's evolving needs as it grows.