Course Content
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Course Overview & What We're Building
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Course Overview & What We're Building
8:24 · video
Q&A
3 questions for this lesson
Why does useEffect run twice in development mode? My API is being called twice and it's causing issues with my free-tier limits.
Great question! In React 18 Strict Mode, effects intentionally run twice in development to help you find bugs. This only happens in development — not in production. The fix is to implement proper cleanup in your useEffect. I cover this in detail in Section 4, Lesson 12.
Is Zustand better than Redux Toolkit for a mid-sized app? I'm starting a new project and want to make the right choice from the beginning.
The Tailwind purge config in the course uses a different syntax than the latest version. Should I follow the course or use the new v3 config?