This guide provides an objective overview of how iOS developers can run tests in parallel on Bitrise build pipelines, leveraging the platform's modular architecture to intelligently execute tests only for changed components, thereby accelerating feedback cycles and optimizing the testing phase. By setting up a two-stage pipeline structure, configuring conditional workflows, detecting changes and setting variables, and executing module-specific tests, developers can significantly reduce wait times for test results while maintaining code quality. The guide offers a step-by-step approach to implementing parallel testing in Bitrise pipelines, with a focus on shared build workflows, wrapper workflows, and environmental variable management.