Scaling a Static Site to 4,400 Pages Without Breaking Google

I built Luxury Hotel Offers , a fully static site with 3,400+ listings that generates 4,400 HTML pages at build time. No SSR, no database at runtime. Here are the four hardest scaling problems I hit. 1. Googlebot's 2 MB HTML Limit With 3,400 hotels on one listing page, the naive approach (render all cards in HTML) produced a 9 MB page. Googlebot truncates at 2 MB and ignores the rest. The fix: cap the initial HTML at 400 cards. The remaining 2,500+ cards are generated as a separate HTML fragment file at a predictable URL ( /data/cards/{slug}-remaining/ ). A "Load More" button injects 48 cards at a time from the fragment. The first search or filter interaction loads the entire fragment so all cards are available for client-side filtering. This keeps every page under 2 MB for crawlers while giving users access to everything. 2. Content-Aware Lastmod with Cascading A site with 4,400 pages can't update every lastmod on every build. Search engines treat that as spam, and IndexNow has rate implications. Instead, the build hashes each hotel's SEO-relevant fields and compares against a persisted store. Only pages with actual content changes get their lastmod bumped. The interesting part is cascading: when a hotel in Paris changes, the Paris city page, France country page, and Europe region page all get their dates updated too, since their content changed (they list that hotel). Changed URLs feed into IndexNow so only genuinely modified pages get pushed to search engines. 3. DOM Filtering Breaks on Mobile at Scale The site started with pure DOM filtering: every card has data-* attributes for region, country, brand, and perks. JavaScript reads attributes and toggles visibility. Zero network requests, instant results. Great on desktop. On a mid-range phone with 2,500+ cards in the DOM, filtering took 2-3 seconds per interaction. textContent traversal across 20-40 nodes per card means ~60,000 DOM visits per keystroke. Layout thrashing with 10,000+ nodes made every show/hide cyc