Can you guide react js interview preparation

Basic CSS, Tailwind, SCSS, SASS. Just theory of SCSS and SASS is good enough to begin with and move on to other topics, but come back later to explore coding with them.

Basic Javascript - DOM manipulation, fetch, loops, mapping, find, filter

⁠Typescript - very important. You should be able to write in TS, implement type interfaces, define types, etc.

⁠Cookies, LocalStorage, difference between the two. Learn what XSS attacks and CSRF attacks are, and in what cases are Cookies better than LocalStorage, and vice-versa.

⁠useState

⁠useEffect

⁠useRef

⁠useMemo

⁠useReducer

⁠react-router-dom, and overall how routing works with react.

⁠Dynamic routing, query params, implementing auth.

⁠Auth tokens - JWT token vs Bearer token vs OAuth2. How all of this is implemented on the frontend. You need to be able to CODE an auth flow by yourself. Just knowing the theory is not enough. Check out Clerk, Firebase, etc. too.

⁠Context API, Providers, custom hooks.

⁠Redux, Redux Toolkit, and the difference between both. It’s fine if you can simply code using redux toolkit. Legacy redux coding knowledge is not too important INITIALLY, because it’s not too hard to pick up on, in my experience.

⁠When to use Context API and when to use Redux.

⁠Server-side rendering vs client-side rendering. How to implement SSR in plain React using an ExpressJS layer. Also learn about Static Site Generation - SSG, and how it’s different from SSR. Not many people can do this, so it’s an added advantage.

⁠Next.js - advantages over React. Implementing SSR and SSG and ISR in Next. Routing in next.

⁠Difference between pages router and app router in Next.

⁠NextAPI, NextAuth.

⁠Tanstack - React Query. Very important