Building JavaScript Frameworks to Conquer eCommerce

SPA frameworks like Next.js, Nuxt, and SvelteKit dominate frontend development, but they carry significant JavaScript overhead that hurts performance-critical use cases like eCommerce. Multi-Page Application (MPA) frameworks such as Marko, Astro, and Qwik take a fundamentally different architectural approach—sending far less JavaScript to the browser by keeping server-only components truly server-side. Marko demonstrated 60–84% savings in JS bundle size on eBay pages using this approach. React 18's Server Components and Streaming SSR help but don't fully close the gap. For sites where initial load performance directly impacts revenue, MPA-oriented frameworks offer optimizations that SPA architectures structurally cannot match.