The Elastic CI Stack for EC2 Mac is a new open-source solution designed to help mobile teams scale their CI/CD pipelines by leveraging AWS and Buildkite, offering increased reliability, security, and speed. Pinterest's own mobile CI pipelines, which utilize a similar architecture, experienced significant improvements, including an 80% reduction in build failures and a 43% decrease in upgrade times after migrating from self-managed hardware to this system. The 1.0 release includes a CloudFormation template that manages an Auto Scaling Group and Launch Template customizations for running the Buildkite Agent on EC2 Mac instances. Future updates will include support for M1 processors and new autoscaling options. Teams interested in exploring this solution can access documentation on GitHub or engage with communities such as the Mobile Native Foundation forums and the Buildkite Community Slack for further collaboration and support.