How One Developer Cut 15 Tool Pages to Under 2-Second Load Times

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A frontend developer optimized a React-based utility platform called TinyUtils, bringing first contentful paint down to 1.2 seconds and time to interactive to 1.8 seconds on 4G. The key changes included code-splitting with React.lazy, which reduced the initial bundle from roughly 800KB to 220KB. Non-critical page content was deferred using Intersection Observer, while images were converted to WebP and AVIF formats, cutting average image sizes by around 60%. Dependency auditing replaced heavy libraries like moment.js and lodash with lighter alternatives, trimming another 150KB from the bundle. Combined with Vite build optimizations and Brotli compression, the site's Lighthouse performance score improved from the 50s to the 90s.

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