Abstract: Presubmit testing is employed in a manner that can significantly reduce processing resources and time to validate code modules. In one aspect this includes identifying components to be subject to presubmit testing, building a set of tests for the components, analyzing the set of tests to identify any tests that are hermetic, segregating identified hermetic tests from any non-hermetic tests including identifying whether any of the hermetic tests would be affected by a current change, and performing presubmit testing on all of the non-hermetic tests and on only the hermetic tests that would be affected by the current change. For any of the components that pass the presubmit testing, those components can be stored in a code repository. Thus, if a hermetic test package is determined to be unaffected by a given change, then that test will be skipped in presubmit testing.