How tree-shaking keeps icon libraries from bloating your JavaScript bundle

Tree-shaking is a build-time technique where bundlers like Webpack, Rollup, and Vite eliminate unused JavaScript code by statically analyzing ES module imports and exports. Icon libraries are particularly prone to bundle bloat when built incorrectly, such as using a single runtime registry or CommonJS format, which forces bundlers to retain every icon regardless of how few are actually used. The GeoIcons library avoids this by giving each icon its own named export with no central lookup table, meaning only the icons explicitly imported are included in the final build. For tree-shaking to work, a library must ship true ES modules and declare itself free of import-time side effects; failing either condition causes bundlers to conservatively keep all code. The practical result is that an app importing three icons from a 799-icon library ships only those three components.