dotJS 2019
2019-12-05..2019-12-06
Paris, France
dotJS ·
[dotJS 2012, dotJS 2013, dotJS 2014, dotJS 2015, DotJS 2016, dotJS 2017, dotJS 2018, dotJS 2019, dotJS 2024, dotJS 2025, dotJS 2026]
who it's for
frontend developers, React developers, framework authors, build and tooling engineers, performance engineers, web testing engineers, browser engineers, WebAssembly developers
topics
local-first CRDT sync with HLC; React Hooks vs Composition API; Svelte compiler change invalidation; Rollup source-map performance fixes; TypeScript custom transformers; Rust to WebAssembly with wasm-pack; DOM Testing Library practices; jsdom web component mocking; routing path scoring and URLSearchParams; audio and MIDI processing in JavaScript
| title | author | length |
|---|---|---|
| CRDTs for Mortals | James Long | 21m |
Argues that local‑first apps are practical by showing a real personal finance app that uses CRDTs, hybrid logical clocks and SQLite on top of a message table… | ||
| State of Components | Evan You | 24m |
Compares three concrete designs — React Hooks, Vue Composition API, and Svelte 3 — and argues components are shifting away from class instances toward stateful… | ||
| Fast by default: algorithmic performance optimization in practice | Vladimir Agafonkin | 23m |
Practical specifics: Chrome DevTools profiling isolates a source-map hotspot in Rollup where magic-string generates then decodes a map — removing the double… | ||
| Architecting A Component Compiler | Adam Bradley | 16m |
A component compiler generates framework‑agnostic web components from one source and proves it with numbers and artifacts not promises. It uses TypeScript… | ||
| The complexity in simplicity | Sara Vieira | 19m |
Buttons in an editor actually perform concrete tasks: adds NPM via unpkg, zips project in browser, and a deploy button pushes a sandbox to Netlify — built and… | ||
| JavaScript Saves the World | Asim Hussain | 17m |
Data centers emit about 3% of global greenhouse gases and electricity generation causes roughly 30% of emissions, so software choices matter: an average Dell… | ||
| Develop, Debug, Learn? | Christian Heilmann | 19m |
Argues that web development loses users and maintainers by hiding platform details and piling abstractions and shows concrete fixes: use lightweight online… | ||
| What to expect from a modern web framework? | Tim Neutkens | 21m |
Web frameworks claim to save time by shipping concrete defaults and optimizations: Next.js grows to 11 million downloads in 2019 and the web shows 350,000… | ||
| Into WebAssembly | Vlad Filippov | 18m |
WebAssembly actually speeds real code: a 2x hash rewritten in Rust and compiled with wasm-pack + webpack plugin runs the same 100k / million iterations in… | ||
| The pragmatic front-end tester | Adrià Fontcuberta | 17m |
Claims that front-end testing can be simple, demonstrates a tiny counter component, and shows a real test that renders the component, queries it with… | ||
| Testing native js web components | Andrew Desmarais | 04m |
Shows how to test native JavaScript web components without a browser by mocking the DOM: jsdom lacks web components support so the solution treats window as an… | ||
| Modern Routing | Eduardo San Martin Morote | 17m |
Explains how browser history APIs like pushState/replaceState and location parts (path, search, hash) become the objects routers match against, demonstrates… | ||
| Programming in the 4th Dimension - Making Time Make Sense | Maggie Pint | 19m |
JavaScript's Date is an incomplete, mutable model that misparses ISO strings, mishandles DST gaps and odd offsets like Nepal's +5:45, and causes real-world… | ||
| Regular expressions my secret love | Stefan Judis | 05m |
Walks through concrete regex tricks and shows what actually changes results: use non-capturing groups to stop unwanted array entries, name captures with… | ||
| TC39: How we work, what we are working on & how you can get involved | Daniel Ehrenberg | 21m |
Committee process runs on staged proposals and concrete artifacts: stage 4 means two+ implementations and a shared test suite, stage 3 features have browser… | ||
| More WebAssembly in your JavaScript | Sven Sauleau | 14m |
Shows concrete wins and what's usable now: ECMAScript module integration is shipping in webpack loaders so C or .wasm files import like normal modules with hot… | ||
| Typing correctly matters | Ziad Bizri | 05m |
Guidelines emphasize concrete techniques: prefer TypeScript inference over manual annotations, replace optional fields with union types and discriminated… | ||
| MIDI, communications, and music in JavaScript | Kassian Wren | 14m |
Builds a JavaScript band: a Rocksmith cable proves proprietary so an ABY split feeds a Sonuus USB MIDI converter into a Raspberry Pi which runs npm packages… | ||
| Escaping flatland: a romance of data science in the browser | Jana Beck | 18m |
Browser-side dimensionality reduction runs with UMAP inside Web Workers using transferable objects to pass Float32Array buffers zero-copy, and OffscreenCanvas… | ||
| Exploring the hidden potential of sound data | Charlie Gerard | 20m |
Claims that everyday microphones plus Web Audio API and TensorFlow.js can do acoustic activity recognition, not word spotting but classifying actions (cutlery… | ||
| Modeling Your Way to Consistency | Christian Gill | 05m |
Argues that encoding domain rules in the type system removes whole classes of bugs instead of covering them with tests, and demonstrates it on a stateful… | ||
| nothing matches | ||