Decoding Javascript: Loading Performance

on YouTube ↗23m

" summary

Starts from a 3.05 MB first-chunk (not gzipped) problem and shows concrete fixes: analyzing bundles with webpack/Rollup artifacts, fixing a module side effects misconfiguration, removing whole-package imports (Sentry, Lodash), and applying code splitting and conditional/import-on-interaction to cut payloads. Results move from ~2.8 MB (gzip ~800 KB) toward 1.2 MB (gzip ~400 KB), market target ~300–400 KB; delivery uses CDNs, HTTP/2, service workers and a backend migration to Apache Druid for real speed gains.

AI-written summary · about

" chapters (6)

1. 0:00JavaScript loading perf
2. 3:42Front-end perf matters
3. 6:55Ship less JavaScript
4. 14:55Smarter JS delivery
5. 18:25Lighter JS with caching
6. 21:54Key takeaways

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