Serve hashed client chunks as immutable so warm page loads stop revalidating all 186 - #6684
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atomantic merged 2 commits intoSep 9, 2026
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…idating all 186 The built UI was served with express.static defaults, so every content-hashed chunk under /assets/ went out with `Cache-Control: public, max-age=0`. A browser treats that as stale on arrival: measured against a spare-port server with a request-counting proxy and Chrome with service workers blocked (the default plain-HTTP tailnet posture, where no service worker can register), a warm dashboard load re-sent all 186 chunks as conditional GETs and got 186 304s back before the app could start. Over HTTP/1.1 at six connections per host that is ~31 sequential round-trip waves of pure revalidation on every reload. Vite renames a chunk whenever its bytes change and the `no-cache` index.html is what points at the current set, so `/assets/**` is safe to serve with `immutable, max-age=1y`. `mountClientDist` in services/assetMounts.js does that as a first tier and keeps the revalidate-per-load default for the rest of dist/ — `sw.js`, `manifest.json`, `fonts/`, `sky/`, `hdri/` are client/public files copied under stable names whose bytes do change. `index: false` stays on both so `/` still reaches the build-id-stamped SPA fallback, and a chunk the current build no longer ships still misses both tiers and 404s, which the stale-chunk reload depends on. Same measurement after the change: 0 asset requests on a warm load or reload, and a warm navigation to a not-yet-visited route fetches only its own new chunks (14 instead of 42).
…her than not HTML
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Summary
express.staticdefaults, so every content-hashed chunk under/assets/went out asCache-Control: public, max-age=0, which a browser treats as stale on arrival. Measured with a request-counting proxy in front of a spare-port server and Chrome with service workers blocked (the default plain-HTTP tailnet posture, wheresw.jscannot register): a warm dashboard load re-sent all 186 chunks as conditional GETs and got 186304s back before the app could start.mountClientDistinservices/assetMounts.jsserves/assets/**aspublic, max-age=31536000, immutableand keeps the revalidate-per-load default for the rest ofdist/(sw.js,manifest.json,fonts/,sky/,hdri/areclient/public/files copied under stable names whose bytes do change).index: falsestays on both tiers so/still reaches the build-id-stamped SPA fallback, and a chunk the current build no longer ships still 404s, which the stale-chunk reload relies on./settingsfetches only its own 14 new chunks (was 42)./assets/requests//settingsTest plan
server/services/assetMounts.test.js: hashed chunk carries the immutable header;sw.jsandmanifest.jsonkeeppublic, max-age=0with an ETag;/reaches the SPA fallback, not the raw index.html; a stale chunk 404s instead of getting the SPA index.scripts/dev-proxy-drift.test.js(readsserver/index.jsas data) plus every other suite that readsserver/index.js: 703 tests green./assets/index-*.js→public, max-age=31536000, immutable;/sw.js→public, max-age=0;/→no-cache;/assets/index-STALEHASH.js→ 404 JSON.dist/.