Buildkite has undergone a significant transformation by evolving its infrastructure from manually managed servers to a fully autoscaling cluster, with workloads segmented and managed through a pipeline that integrates configuration as code using Terraform and Packer. This change was facilitated by leveraging a collaborative workflow involving GitHub and Buildkite, where infrastructure changes are managed similarly to application code, using pull requests and automated testing. The pipeline is designed to ensure security and concurrency while allowing for transparent monitoring of infrastructure changes. The infrastructure's remote state is maintained in an S3 bucket, and Buildkite's concurrency groups help avoid state conflicts. Additionally, the pipeline intelligently determines when to build new machine images using Packer, ensuring efficient resource management. Buildkite's system is designed to function independently but also benefits from integration with Buildkite's own platform, with secure and segregated environments for operations builds. This approach allows for scalable, secure, and efficient management of infrastructure changes, while maintaining the flexibility to run tasks manually if needed.