Core Web Vitals

lazy-load heavy UI and optimize images

// Topic: Core Web Vitals
const perf = { images: 'optimized', payload: 'small' };
console.log(perf.images + ':' + perf.payload);

// Expected Output: optimized:small

• 1Define what Core Web Vitals owns across pages, layouts, composables, server routes, state, and deployment. Use the focus terms (core, web, vitals, reference UA318CB) to keep this lesson tied to its exact Nuxt.js topic.
• 2Document delivery optimization specialized for Core Web Vitals with focus terms: core, web, vitals, reference UA318CB in the smallest useful page, layout, composable, store, server route, or deployment step.
• 3Represent every loading, success, denied, stale, and failure state that Core Web Vitals can expose.
• 4Test the primary path, one SSR/client boundary, and one failure case for Core Web Vitals. Include a check for these focus terms: core, web, vitals, reference UA318CB.
• 5Use LCP, CLS, INP, and payload size for Core Web Vitals tracked for core, web, vitals, reference UA318CB to guide improvements.
• 6Start with clear requirements and one minimal working example.
• 7Use meaningful names that explain business intent.
• 8Keep examples small enough to debug line by line.
• 9Validate input at every trust boundary.
• 10Handle errors explicitly and preserve useful context.
• 11Prefer simple control flow over deeply nested logic.
• 12Separate domain logic from I/O and framework code.
• 13Write tests for normal, boundary, and failure cases.
• 14Review security assumptions before production use.
• 15Measure performance before optimizing.
• 16Document non-obvious decisions close to the code or in project notes.
• 17Use official documentation when behavior is version-specific.
• 18Keep dependencies current and remove unused code.
• 19Avoid hardcoded secrets, credentials, and environment-specific paths.
• 20Log operational events without exposing sensitive data.
• 21Design examples so learners can safely modify and rerun them.
• 22Prefer maintainability over short-term cleverness.