Performance

Core Web VitalsPage SpeedCachingLoad Testing

Master performance engineering to build blazing-fast web applications. From Core Web Vitals to full-stack optimization and performance culture.

Free Tutorial

Learn Performance Engineering - Build Blazing-Fast Web Applications

Master web performance optimization from fundamentals to advanced techniques. Learn Core Web Vitals, Lighthouse auditing, image and font optimization, code splitting, server-side rendering, caching strategies, load testing with k6, and how to build a performance-first engineering culture.

Prerequisites

Before diving into performance engineering, you should be comfortable with HTML, CSS, JavaScript/TypeScript, and have basic familiarity with React or Next.js.

Next.js Tutorial TypeScript Tutorial

What You'll Learn

✓ Core Web Vitals (LCP, INP, CLS)
✓ Lighthouse & PageSpeed Insights
✓ Image & font optimization
✓ Code splitting & tree shaking
✓ SSR, streaming & React Server Components
✓ Edge computing & CDN optimization
✓ Database & API performance
✓ Redis caching & connection pooling
✓ Load testing with k6
✓ Performance budgets & monitoring

Course Topics

Lesson 1

Beginner

20 min

Web Performance Fundamentals

Understand why performance matters, key metrics, and the foundations of building fast web experiences

Core Web Vitals Deep Dive

Master LCP, INP, and CLS — the metrics Google uses for search ranking and user experience assessment

Lighthouse & PageSpeed Insights

Use Lighthouse programmatically, interpret scores, and automate performance audits in CI/CD pipelines

Critical Rendering Path

Optimize the browser's rendering pipeline from HTML parsing to pixels on screen for faster page loads

Master modern image formats, responsive images, lazy loading, and Next.js Image component for optimal delivery

Eliminate font-related layout shifts and render blocking with optimal loading strategies and subsetting

Code Splitting Strategies

Reduce initial bundle size with dynamic imports, route-based splitting, and component-level lazy loading

Eliminate dead code from your bundles with ES modules, sideEffects configuration, and proper import patterns

Visualize and audit your JavaScript bundles to identify bloat, duplicates, and optimization opportunities

Server-Side Rendering Performance

Optimize SSR, streaming, React Server Components, and hydration for fast server-rendered applications

Deploy code at the edge for ultra-low latency using Edge Functions, Middleware, and edge-first architecture patterns

Configure CDNs for maximum cache hit rates, optimal headers, and intelligent content delivery strategies

Database Query Optimization

Write efficient SQL queries, use proper indexing strategies, and analyze query execution plans for faster data access

Caching Strategies Full Stack

Implement multi-layer caching from browser to database with cache invalidation patterns and stale-while-revalidate

Implement Redis for session caching, rate limiting, leaderboards, and distributed caching patterns

Manage database and HTTP connections efficiently with pooling, keep-alive, and connection lifecycle management

Optimize REST and GraphQL APIs with response compression, pagination, field selection, and batching strategies

Write k6 load test scripts, simulate realistic traffic patterns, and identify performance bottlenecks under load

Set and enforce performance budgets for bundle size, load time, and Core Web Vitals to prevent regressions

Monitoring & Alerting

Build real-time performance dashboards, set up alerting on regressions, and implement Real User Monitoring (RUM)

Build a performance-first engineering culture with ownership, education, processes, and performance champions

Optimize for mobile devices with constrained CPUs, limited bandwidth, touch responsiveness, and battery awareness

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Frequently Asked Questions

What are Core Web Vitals?

Core Web Vitals are a set of three specific metrics defined by Google that measure real-world user experience on web pages. They include Largest Contentful Paint (LCP) measuring loading performance, Interaction to Next Paint (INP) measuring interactivity responsiveness, and Cumulative Layout Shift (CLS) measuring visual stability. These metrics directly impact search rankings and user satisfaction.

How to improve website performance?

To improve website performance, start by optimizing images with modern formats like WebP and AVIF, implement code splitting and lazy loading, minimize render-blocking resources, use efficient caching strategies, and optimize your critical rendering path. Tools like Lighthouse and PageSpeed Insights help identify specific issues. Server-side rendering, CDN deployment, and database query optimization provide additional gains for full-stack applications.

What is the critical rendering path?

The critical rendering path is the sequence of steps the browser takes to convert HTML, CSS, and JavaScript into pixels on the screen. It includes constructing the DOM and CSSOM trees, running JavaScript, building the render tree, computing layout, and painting pixels. Optimizing this path by reducing render-blocking resources, deferring non-critical CSS/JS, and minimizing DOM size directly improves page load speed.

What tools are used for performance testing?

Key performance testing tools include Google Lighthouse for auditing page performance, Chrome DevTools Performance panel for runtime profiling, WebPageTest for detailed waterfall analysis, and k6 for load testing APIs and backend services. Real User Monitoring (RUM) tools like Google Analytics and SpeedCurve track field performance data, while synthetic monitoring catches regressions before they reach users.

Ready to Master Performance Engineering?

Begin with the fundamentals of web performance. You'll learn why performance matters, key metrics to track, and how to measure your baseline.

Start Learning Performance →