Rethinking reactivity
summary
Claims that reactivity moves reactivity into the language by compiling components so assignments trigger updates, using compiler instruments assignments with invalidate calls and labelled statements ($:) to express derived values. The concrete result is a compiled runtime with bindings, CSS-scoped styles, transitions and a Sapper app framework; benchmarks claim about 35× faster than React (50× vs Vue in an older test). Examples include low-powered POS and smart‑TV apps where the compiled output actually works and cuts bundle/runtime cost.
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chapters (32)
- 0:00Spreadsheets and reactive programming
- 1:56VisiCalc and Lotus 1-2-3
- 2:38Talk intro
- 3:19React impact and limits
- 4:22Virtual DOM in React
- 5:26Virtual DOM inefficiency
- 6:28React abstraction leaks
- 7:11Compilers as frameworks
- 8:16Svelte state management
- 9:18Svelte 3 reactivity
- 10:45Svelte compile optimizations
- 11:50Derived state in components
- 13:13React to Svelte conversion
- 13:56Topological ordering
- 15:00Labeled statement trick
- 16:27Svelte reactivity under hood
- 17:31Svelte compile-time vs runtime
- 18:55Concurrent mode React vs Svelte
- 21:40Virtual DOM vs Svelte performance
- 23:04Incremental performance limits
- 24:48Reliable speed-up method
- 25:31Svelte success stories
- 26:34Svelte accessibility
- 27:59Scoped styles in Svelte
- 29:08Unused CSS removal
- 29:52Smooth Svelte transitions
- 31:16Custom Svelte animations
- 32:43Svelte list reordering
- 33:45Decoupling features
- 34:27Sapper and Svelte Native
- 35:31Web dev as spreadsheets
- 36:33Closing thoughts
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