Test Flakiness – Methods for identifying and dealing with flaky tests

This post details Spotify's journey in addressing test flakiness, introducing three key systems: Odeneye for visualizing test suite results and differentiating flakiness from infrastructure problems, a simple reporting table that demonstrably reduced flakiness by making results visible, and Flakybot for pre-merge validation of test stability. It also outlines common causes of flakiness such as inconsistent assertion timing, reliance on test order, and the inherent brittleness of end-to-end tests.