fix(web): faster server response + no layout shift on load and transitions - #136
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damianrosellen1 wants to merge 3 commits into
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fix(web): faster server response + no layout shift on load and transitions#136damianrosellen1 wants to merge 3 commits into
damianrosellen1 wants to merge 3 commits into
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The proxy fetched siteLanguageSettings on every page request, and with SANITY_API_READ_TOKEN set (any deploy with Visual Editing) it always used the drafts perspective against the live API — uncached, no CDN. Every cold start and every 60s TTL expiry blocked the response on that round trip; locally measured 1.0s cold / ~150ms steady-state TTFB, worse on serverless where isolates recycle constantly. - proxy: published perspective via the CDN host for regular traffic; drafts only for requests that carry the Draft Mode cookie (and in dev), fetched per request and never written to the shared cache - proxy: stale-while-revalidate with a single-flight refresh — an expired cache entry is served immediately while one background refresh runs, so only the first request of a process ever waits for Sanity - render path: fetchSiteLanguageSettings gates the drafts client on draftMode().isEnabled (or dev) instead of token presence, falling back to the existing unstable_cache'd published path; draftMode() throwing outside request scope (generateStaticParams) is treated as disabled Presentation previews of unpublished language changes keep working — draft-mode requests still resolve drafts in both proxy and render path. Side effect: sitemap.xml revalidate drops 1h -> 60s because the language settings read now participates in unstable_cache instead of bypassing Next's cache entirely. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
- next/font display: block -> swap. block hid all text for up to 3s while Geist loaded; swap paints immediately in the metrics-adjusted fallback next/font generates, so the swap itself doesn't shift layout. - Thread a priority flag from ModulesRenderer (module index 0) into ModuleMedia (image / video / loop poster) and ModuleContentRefs (first card image). The first module is the LCP candidate, but every image rendered as loading=lazy with a fade-in from opacity 0 — the LCP image of a media-first page was deferred and then faded in. Priority media loads eager + fetchpriority=high and skips the fade. Rich-text-embedded media (project body) intentionally stays lazy — an image mid-text isn't reliably above the fold. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Two shifts fired on client-side navigations: - Scrollbar appear/disappear between short and scrollable pages shifted the whole layout horizontally on classic-scrollbar systems (Windows/Linux). scrollbar-gutter: stable on <html> reserves the gutter permanently. - The route-loading skeleton painted on every navigation, then got replaced by real content — a visible skeleton -> content jump even though ISR + prefetch resolve most navigations in well under 300ms. The skeleton now stays invisible for 300ms (opacity keyframe, both fill mode) so fast navigations never show it; genuinely slow loads (draft mode, cold cache) still get feedback after the delay. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Fixes the two reported performance problems: slow initial loading / server response time, and CLS on initial load and page transitions.
Problem 1 — Server response time (TTFB)
Root cause: the proxy (middleware) blocked every page request on a
siteLanguageSettingsfetch. WithSANITY_API_READ_TOKENset — i.e. on any deploy with Visual Editing — that fetch always used the drafts perspective against the live API (no CDN, no shared cache). Every cold start and every 60s TTL expiry paid a full Sanity round trip before even a fully static page could be served. The render path (fetchSiteLanguageSettings) had the same token-gated drafts fetch on every render.Fix (
97f4fe4):fetchSiteLanguageSettingsgates the drafts client ondraftMode().isEnabledinstead of token presence and otherwise uses the existingunstable_cached published path (tag-invalidated via/api/revalidate).Local
next startmeasurements (homepage, token set):The structural win matters most on serverless, where every new isolate paid the blocking fetch.
Problem 2 — CLS on initial load and transitions
Three independent causes, three fixes:
a5d9827):display: "block"hid all text for up to 3s while Geist loaded. Nowswap— text paints immediately in the metrics-adjusted fallback thatnext/fontgenerates, so the swap itself doesn't shift layout.a5d9827): every image renderedloading="lazy"+ fade-in fromopacity: 0, including the first module's media.ModulesRenderernow threadspriorityinto module index 0 (ModuleMediaimage/video/loop poster,ModuleContentRefsfirst card) → eager +fetchpriority=high, no fade. Rich-text-embedded media intentionally stays lazy (mid-text images aren't reliably above the fold).78f69f7):scrollbar-gutter: stableon<html>— the scrollbar appearing/disappearing between short and scrollable pages shifted the whole layout horizontally (Windows/Linux).Side effects / notes
sitemap.xmlrevalidate drops 1h → 60s (the language-settings read now participates inunstable_cacheinstead of bypassing Next's cache)./api/draft-mode/disableclears it.Verified
pnpm typecheck,pnpm formatclean; production build green, all routes still SSG/ISR/de200,/en→ 307/,/en/docs→ 307/docs,/de/docs200font-display: swap,scrollbar-gutter: stable, and the 300ms skeleton delay present in the built CSS🤖 Generated with Claude Code