AWS is now offering MAC EC2 (Elastic Compute Cloud) instances to build, test, package and sign Xcode app for the Mac platform including macOS, iOS, iPadOS, tvOS, watchOS, and Safari.
Mac instances with the Apple m1 chip are planned for 2021.

You can use these instances to create build farms, render farms, and CI/CD farms that target all of the Apple environments that I mentioned earlier. You can provision new instances in minutes, giving you the ability to quickly & cost-effectively build code for multiple targets without having to own & operate your own hardware. You pay only for what you use, and you get to benefit from the elasticity, scalability, security, and reliability provided by EC2.

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