Problem: How can the performance of the React website be improved?

Answer: As soon as this question is asked, do not jump; try to answer everything you know about efficiency.

Primarily, we can divide efficiency into 4 parts.

Ask the interviewer what optimisation they are really interested in? Answer accordingly. Ex: if they are concerned about loading time, then speak about the light house score, how do you check the loading time in the performance tab, etc.

  1. Code level

  2. Caching

Ask the interviewer what optimisation they are really interested in? Answer accordingly. Ex: if they are concerned about loading time, then speak about the light house score, how do you check the loading time in the performance tab, etc.

if it is caching, how do you optimise the caching process? mention it in the comments section.

How will you optimise a React app's performance?

There are two things to consider here.

  1. Optimising React code

  2. General Frontend performance concepts

For React, you can

  1. Reduce build size

  2. Add code splitting

  3. Reduce re-renders

  4. memoise components and computational values

  5. lazy load components

  6. Virtualise long tables or lists

  7. Use the correct keys for list render mapping.

General Grontend concepts comprise

  1. Use CDN

  2. Minify assets

  3. Optimise images and prefer sprite images for initial load

  4. Preload important webpage data or assets

  5. Cache efficiently

  6. defer non-critical JS/CSS load

  7. Reduce third-party scripts