Engrain by ByteRush

QLT.01 6 concepts · 4 ready

Performance and Core Web Vitals

Measure, diagnose and improve real-user performance.

  1. QLT.01.01Core Web Vitals: LCP, INP, CLSCoreMid-level11 min
  2. QLT.01.02Optimising LCPCoreMid-level11 min
  3. QLT.01.03Optimising INPCoreMid-level12 min
  4. QLT.01.04Optimising CLSCoreJuniorBeing written
  5. QLT.01.05JavaScript and asset budgetsCoreMid-level11 min
  6. QLT.01.06Real-user monitoring and performance cultureSeniorBeing written

Interview questions in this module

  1. What are Core Web Vitals and their "good" thresholds?
  2. How would you improve LCP on an image-heavy homepage?
  3. What is INP? How do you debug a poor INP score?
  4. What causes layout shifts and how do you prevent them?
  5. Why do Lighthouse scores differ from real-user data?
  6. How do you keep a large app's bundle size under control over time?
  7. How would you optimise a site for users on low-end Android phones on 3G?
  8. How do you handle the performance cost of third-party scripts?