Performance audit and fixes across all three sites

Ran performance audits on all three SvelteKit sites and implemented fixes for the major bottlenecks found.

Docsite — 99% client bundle reduction

The docsite was shipping a 1,287KB client bundle. Root cause: src/lib/format.ts mixed client-safe formatDate with server-only markdown parsing (unified/remark/rehype), pulling the entire markdown pipeline into the browser.

Fix: split formatDate into src/lib/date.ts (client-safe), rewrote src/lib/format.ts as server-only. Also removed @ewanc26/ui as a runtime dependency — it was re-exporting createSiteMeta which pulled in @atproto/api and hls.js transitively. Defined SiteMetadata interface locally instead.

Result: client bundle 1,287KB → 12KB. Total immutable assets: 172KB (down from 1.5MB).

Devlog — layout data and caching

The root layout was serialising the full post list (~64KB JSON) into every prerendered page, but the layout component never used data.posts. Only the home page needs it (and already loads it from its own +page.server.ts).

Fix: removed listPosts() from the layout server load. Added module-level caching for listPosts() to avoid repeated filesystem reads. Merged renderMarkdown and extractToc into a single parse pass — the AST is parsed once, TOC extracted, then the rehype pipeline runs.

Result: homepage HTML 156KB → 127KB. __data.json 64KB → 32KB.

Website — duplicate fetches and polling

The Footer was re-fetching profile and site info on mount even though the layout already loads them. BlueskyPostCard was polling every 2 minutes regardless of tab visibility.

Fix: pass profile and siteInfo from layout to Footer as props. Gate BlueskyPostCard polling to visible tabs via visibilitychange API, using recursive setTimeout instead of setInterval.

Also filtered the recent posts card to only show blog posts (devlog publication), not documentation.

Self-hosted fonts

All three sites now self-host Inter and JetBrains Mono instead of loading from Google Fonts. Removes the extra DNS/TLS connection, render-blocking CSS, and third-party dependency. Font files are 31-85KB each with unicode-range splitting for efficient loading.