React’s useEffect: The Hook That Hooks You If You’re Not Careful

useEffect() is that one hook every React dev uses and every React dev breaks at least once.

If you’ve ever caused an infinite loop, forgot to clean up a listener, or watched your API call fire 4,000 times that means you’re not alone. 👀

But when used right, useEffect() can be a powerful tool for managing side effects, syncing state, and structuring logic cleanly.

Here’s a real-world example 👇

✅ We’re fetching API data when a component mounts

✅ No double calls

✅ No stale state

✅ No memory leaks

Plus, we’ll show a screenshot of what the component state looks like after load, so you can visualize how things flow.

🧠 Bonus: We also included 3 mistakes we see all the time in the wild:

• Missing the dependency array
• Incorrect dependencies (👋 setState functions!)
• Forgetting cleanup for subscriptions or timers

At @Techlusion, we work with dev teams to:

• Audit React apps for hook hygiene
• Refactor messy state logic
• Help teams build scalable components from the start

Because using useEffect() isn’t about being clever — it’s about being clear.

Over to You:

What’s the worst useEffect() bug you’ve ever created?

👇 Drop your horror story or favorite pro tip — we’re all ears (and side effects).