Frontend Interview Prep OSOne place to learn, revise, practice, and answer well.Live study space: prep.ai-developer.in
3-6y

Loading Strategy, Caching, and Core Web Vitals

Fast apps load important content quickly, stay stable while loading, and respond without delay when the user interacts.

Analogy

A good shop opens the front door first, keeps the shelves from moving around, and serves the first customer quickly instead of making everyone wait for every room to be cleaned.

Follow-up questions

Topic practice prompts

How would you improve LCP on a slow React or frontend page?

Focus on the main content first: reduce heavy JavaScript, optimize the hero asset, improve server response, and prioritize only critical resources.

  • How can image dimensions help performance?
  • Why can too much preloading backfire?
How do you think about caching strategy for frontend assets and API data?

Static assets can usually be cached very aggressively when filenames are versioned, but API data needs freshness rules and user-visible fallback behavior.

  • When would you revalidate in the background?
  • How do you prevent users from trusting stale numbers?
Cheat sheet

Last-day revision lines

  • Prioritize critical content.
  • Keep dimensions stable.
  • Ship less JavaScript upfront.
  • Cache with freshness in mind.
Source references
  • Web performance and security: context/Web perfomance and security.docx
  • Frontend resources gold mine: context/Resources to learn Frontend (Gold Mine)- eBook .docx
Offline study support

Local resource packs for this topic

1 local packs

Use these local packs when you want broader official-source context without leaving the app.

performancePerformance and Web Vitals

Performance and Web Vitals

A local digest of high-value web performance ideas that connect directly to React and product interview rounds.

Performance and SecurityReact.jsFrontend Breadth

Web vitals, LCP thinking, responsiveness, layout stability, render cost, bundle strategy, and main-thread awareness.

Open local study pack
Next step

Related topics to study after this one

Performance and Security3-6y

Web Performance and Browser Security Basics

Know web vitals, bundle cost, rendering cost, XSS, and safe frontend data handling.

Simple mode, interview mode, example, pitfalls, and follow-ups are all inside this topic.

web-vitalssecurityxssbundle-size
Study topic
Browser and DOM3-6y

Browser Render Pipeline and Main Thread Thinking

Explain parsing, style, layout, paint, compositing, and what makes the browser feel janky.

Simple mode, interview mode, example, pitfalls, and follow-ups are all inside this topic.

browserrender-pipelinelayoutpaint
Study topic
Frontend System Design3-6y

Realtime Dashboards and Resilient Data Flow

Prepare for questions about polling, websockets, partial failure, stale data, and resilient UI updates.

Simple mode, interview mode, example, pitfalls, and follow-ups are all inside this topic.

system-designrealtimedashboardpolling
Study topic