Website Performance Optimization — Fix Your Core Web Vitals and Load Times
Your website loads in 4 seconds. Your bounce rate is 40%. Google ranks you lower because your Core Web Vitals fail. The fix is not a bigger server — it is optimizing the critical rendering path, eliminating render-blocking resources, compressing assets, and configuring caching correctly. We analyze your site's performance bottlenecks end-to-end and implement fixes that bring your load time under 2 seconds.
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What Slows Down Websites
Website performance has two sides: server performance (how fast the server generates and sends the response) and client performance (how fast the browser renders the page). Most optimization efforts focus on one side and ignore the other. A fast server with a bloated client-side JavaScript bundle still feels slow. A lightweight frontend served from an overloaded origin still waits seconds for the first byte.
Server bottlenecks: Slow database queries, missing CDN, no response caching, unoptimized images served from the origin, server-side rendering that blocks on slow API calls, and cold starts on serverless functions. The metric is Time to First Byte (TTFB) — how long the browser waits before receiving the first byte of the response. Target: under 200ms.
Client bottlenecks: Large JavaScript bundles that block rendering, unoptimized images that load before they are visible, web fonts that cause text to flash, layout shifts from dynamically sized content, and third-party scripts that block the main thread. The metrics are Largest Contentful Paint (LCP), Interaction to Next Paint (INP), and Cumulative Layout Shift (CLS) — the Core Web Vitals that Google uses for ranking.
A complete optimization addresses both sides. We start with measurement to identify the actual bottlenecks, then implement targeted fixes rather than generic "best practices" that may not apply to your specific site.
Our Optimization Process
Audit: We run Lighthouse, WebPageTest, and Chrome DevTools on your key pages (homepage, product pages, checkout, dashboard). We analyze the waterfall chart to identify blocking resources, the flame chart to identify slow JavaScript, and field data from Chrome UX Report (CrUX) to see real-user performance across devices and geographies. The audit identifies the specific bottlenecks with estimated impact for each fix.
Server Optimization: We optimize TTFB by profiling server-side code, adding response caching for pages that do not change per-request, configuring a CDN for static assets and cacheable pages, and optimizing database queries that back server-rendered pages. For Next.js, we configure ISR (Incremental Static Regeneration) so pages are statically generated and revalidated in the background. For API endpoints, we add Redis caching for expensive computations.
Image Optimization: Images are usually the single largest payload on a page. We configure next-gen formats (WebP, AVIF) with fallbacks, responsive srcset attributes for different viewport sizes, lazy loading for below-the-fold images, and explicit width/height attributes to prevent layout shifts. For Next.js, we configure the built-in Image component with a CDN-backed image optimization pipeline.
JavaScript Optimization: We analyze your bundle with webpack-bundle-analyzer or equivalent, identify oversized dependencies, and implement code splitting to defer non-critical JavaScript. We move third-party scripts (analytics, chat widgets, A/B testing) to load after the page is interactive using async or defer attributes, or load them on user interaction. The goal is to keep the main thread unblocked during the critical rendering path.
Font Optimization: We configure font-display: swap to prevent invisible text, preload critical fonts, subset fonts to include only the characters your site uses (reducing a 200 KB font to 20 KB), and self-host fonts instead of loading from Google Fonts (eliminating a DNS lookup and connection).
What You Get
A comprehensive performance optimization with measurable results:
- Performance audit — detailed analysis of server and client bottlenecks with prioritized fixes
- TTFB optimization — server response under 200ms with caching and CDN
- Core Web Vitals — LCP under 2.5s, INP under 200ms, CLS under 0.1
- Image optimization — next-gen formats, responsive sizes, lazy loading, layout shift prevention
- JavaScript optimization — bundle splitting, tree shaking, deferred third-party scripts
- Font optimization — preloaded, subsetted, self-hosted fonts with swap display
- Monitoring — real-user monitoring (RUM) setup for ongoing performance tracking
- Before/after report — documented improvements with Lighthouse scores and CrUX data
Why Anubiz Engineering
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