Build environments, pipelines, and cloud Mac practices

Split unpredictable system scheduling from testable work so success, failure, cancellation, and repeated execution can be verified consistently.

Treat shared schemes and .xctestplan files as reviewed configuration so local development and CI execute the same targets, options, and environments.

Intermittent parallel failures often come from shared files, preferences, or ports. This guide provides executable isolation rules and a repeatable evidence-collection workflow.