hardDesignScenarioMidSeniorStaff
How do you run a Selenium suite in parallel across a grid without the tests interfering with each other?
6 min readUpdated 2026-08-15Target archetype: Big Tech, Enterprise Captive, Product Startup
Answer
Short answer
Give each thread its own WebDriver session held in thread-local storage, remove every other piece of shared mutable state including test data and static fields, size the run to the grid's slots so requests queue rather than time out, and quit every session even on abnormal exit.
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