React Performance: Bundle Size — Barrel Imports. Keywords: barrel import direct path. Platform: React/Next.js. Description: Import directly from source files instead of barrel files to avoid loading unused modules. Do: Import directly from source path. Don't: Import from barrel/index files. Good Example: import Check from 'lucide-react/dist/esm/icons/check'. Bad Example: import { Check } from 'lucide-react'. Severity: Critical.