Engineering Marketing Sites That Score 95+: A Next.js Performance Checklist
The concrete techniques behind fast Core Web Vitals on content sites — fonts, images, third parties and the JavaScript you didn't need.
NexusNao TeamEngineering
Speed is a business metric
Core Web Vitals correlate with conversion, bounce and search ranking. For a site whose job is generating pipeline, performance is not a technical nicety — it's revenue plumbing.
The usual suspects
Web fonts loaded late shift layout; self-host them with next/font and swap. Hero images without dimensions cause CLS; use next/image or explicit sizes. Third-party scripts are the largest tax — load analytics after consent and interaction, never in the critical path.
JavaScript is the most expensive asset per byte. Server components by default, client components only where interaction demands them, and heavy libraries (3D, charts) behind dynamic imports that load when visible.
Animate on a budget
Animate transform and opacity only — they composite on the GPU. Trigger reveals with IntersectionObserver, run them once, and respect prefers-reduced-motion completely. Decorative WebGL should pause when off-screen and when the tab is hidden.
The test: scroll the page on a mid-range Android phone. If it isn't smooth there, it isn't smooth.