Performance / Core Web Vitals on each at scale?
Both can hit Lighthouse 90+ at $50M scale. Different paths.
Shopify Plus performance characteristics:
- Out of box (Dawn or Plus theme, vanilla): LCP ~1.8s, CLS ~0.03, INP ~150ms, Lighthouse ~85 mobile
- With 8-12 Plus apps installed (typical $50M brand): LCP drifts to 2.5-3.5s, CLS 0.08-0.15, Lighthouse 60-75 mobile, third-party scripts compound
- Hydrogen (Shopify’s React-based headless): LCP ~1.3s if engineered well, but adds an entire ops team to maintain
- Built-in CDN, image lazy-loading, automatic Brotli compression, all defaults are good
Adobe Commerce performance characteristics:
- Out of box (Luma theme): LCP ~3.8s, CLS ~0.12, INP ~280ms, Lighthouse ~45 mobile, bad
- AC + Hyvä theme (Tailwind + Alpine.js, ~95% less JS than Luma): LCP ~1.2s, CLS ~0.02, INP ~80ms, Lighthouse 95+ mobile, beats Plus defaults
- AC + PWA Studio (headless): comparable to Hydrogen, similar ops overhead
- Performance depends on dev discipline: a $50M AC store with poorly-tuned cache hits Lighthouse 60. A well-tuned one hits 95.
Verdict for $50M+ brands: AC + Hyvä is the long-term performance winner because customization happens in your codebase, not in installable scripts. Plus is faster to start but degrades as the app stack accumulates. If Core Web Vitals is a top-3 SEO ranking factor for your category (apparel, beauty, electronics), AC + Hyvä is the safer 5-year bet.