JavaScript Testing Guide 2026 From Jest to Playwright With Real Interview Questions
Testing knowledge separates JavaScript developers who advance to senior positions from those who remain stuck at mid-level despite years of experience. Technical interviews at competitive companies include dedicated testing questions that filter candidates effectively regardless of their other skills. A developer who confidently explains testing strategies, writes clean test code, and demonstrates understanding of when to use different testing approaches moves forward while equally talented developers without testing knowledge get rejected or downleveled to positions paying $20,000 to $40,000 less annually.
