Once again it is time for Europes biggest 🎉. I would like to give you my experience with the conference as well as a rough overview of the talks (will add the video links once they are uploaded). I hope it helps you to get a better understanding why you should come visit next year too and which talks to have a detailed look at. React conference The evening before The organizers of React-Europe had an the day before the conference at a bar near the venue. It was pretty cool; we got free drinks until about 22:00 and afterward a lot of pretty awesome people just bought pitchers and went around to help everyone out. and I were there for about 4 hours, and it was hard to leave because we had so many great conversations with a lot of different people. opening party Daniel Banck Video Coming soon What I Learned Benchmarking React by Dominic Gannaway TL;DR Rollups flat modules helped react to get a ~10% improvement in bundle size and load time Rollup is a good match for improving performance in libraries is a great tool for performance benchmarking Google Lighthouse Video Coming soon Building High-Quality JavaScript Tools by Christoph Pojer TL;DR New features and improved performance made Jest a lot better and increased the adoption to over 100 companies Snapshot tests are great for getting a good coverage and are being compared with having no tests rather then with conventional tests. Jest moved to a modular structure, and the modules are already used in different open source projects Video Coming soon La nouvelle vague by ”) Sunil Pai (“ π TL;DR The new wave is the movement from runtimes to compilers Good examples are , , & which leverage on compilers to reduce their runtime Gatsby next.js relay prepack “If you can’t introduce a library gradually, it’s dead on arrival” Video Coming soon Worse is Better: The Upside of JavaScript Fatigue by Kevin Lacker TL;DR Simplicity is the most important attribute of a software system to determine its success (e.g. React only taking the View layer) Simplicity => Popularity => Contributors (= Fatigue, because new projects pop up very often) Video Coming soon What WebAssembly means for React by Lin Clark TL;DR Current state of Web Assembly may not allow significant performance improvements if the React Reconciler gets ported to Web Assembly Down the line, there could be major improvements to the performance & ecosystem by improved APIs and tooling Video Coming soon Practical Confidence by Adam Perry TL;DR “Types are tests for the structure of your data” Type annotations reduce the cognitive overhead of figuring out the type of variables in your code, also through editor integration Flow has a lot of inference features, so only the exports of a module need to be typed most of the time Video Coming soon Imperfection by Cheng Lou TL;DR Software Engineering means making trade-offs; choosing the right ones is an art Doing 80% with 20% of the efforts is good enough most of the times. This only applies if your foundation (language, type system, etc.) is solid (100%) “Grow your slopiness budget by approaching certain parts as e.g. the foundation with a 100% mentality Video Coming soon Maximally Modular Apps with React Navigation by Eric Vicenti TL;DR demonstrated the power of with react-navigation a small demo app react-navigation can be used in web and native Video Coming soon How Streaming Can Supercharge React by Sasha Aickin TL;DR Time to first render and time to first interaction is important for a business Client Side loading gives a bad user experience, Server Side Rendering is better but has a long time of non-interactive sites Chunked Rendering allows different parts of the application to load individually, which also leads to better fault tolerance Video Coming soon ⚡ Talks : Using components for other things than rendering UI can be valuable, too return null; by Joshua Comeau : They build a CMS frontend with React and Redux which embraces modular design principles Fancy Footwork by Brendan Moore, Sarah Mogin and Serge Rose They built a market place for React Native extensions (think authentication) ShoutemUI by the Shoutem team: He introduced , a way to navigate in React Native just using components Thousand ways to navigate in React Native by Charles Mangwa: react-router-navigation & : They created an E2E testing framework for React Native that is very easy to use, stable and fast Detox by Tal Kol Rotem Mizrachi-Meidan The Apollo team developed a Chrome Extension for developing with Apollo with features like Query watching and Store inspection Devtools for GraphQL by Danielle Man: Second Day And once again guided us through the day. In the morning people came in a bit later than yesterday, a lot have gathered yesterday evening at the frog, where we already met the day before. Brent Vatne Next generation state management by Michel Weststrate TL;DR He introduce , a new way to use the graph-based advantages of MobX and combine them with the tree based advantages of Redux mobx-state-tree He demoed the Redux TODO MVC App with an exchanged MobX reducer and displayed features like time traveling Video Coming soon Composition by Nik Graf TL;DR State in composition is error prone. Therefore we should embrace function programming paradigms as higher-order functions & components He showed how the library and an app with Apollo that used HOC for loading screens polished Video Coming soon The making of Twitter Lite by Nicolas Gallagher TL;DR Twitter Light has a better performance in load time as well as data consumption and time to interaction It doesn’t use Server Side Rendering; he explained why in detail Think about disposability of parts of your application while designing the system Vide0 Coming soon ⚡ Talks Use react-native in the browser on Snack by Brent Vatne : https://snack.expo.io/ See the demo at React Native Components in Android Apps by Petter Hesselberg : https://github.com/petterh/react-europe-demo How pure components and key props improve your performance Quantifying Best Practices by Jackson Hamburger and Louis Antonelli : Intro to dynamic import statements with babel and webpack Leveraging code-splitting by Glenn Reyes : A brief and good introduction to and Smarter code-splitting and preloading by Brandon Dail: react-loadable react-perimeter Configuration leads to many bad effects for open source; add them only when really needed Rise of low-configuration tools by Karl Horky : Exploring Relay Modern by Lee Byron TL;DR Relay Modern shifts assumptions from dynamic queries to static ones, allowing compilers to do ahead of time optimizations These optimizations lead to better performance and less network traffic (900ms win on Facebook Marketplace app) You can introduce Relay Moderns API step by step and once you finished the conversion switch to it completely Video Coming soon Animating the Virtual DOM by Sarah Drasner TL;DR Animation is very important to keep the users attention and reduce perceived waiting times For every job there is the right tool, CSS-in-JS for simple transitions, for sequencial & complex movements, for simple, physics based animations GreenSock React-Motion Video Coming soon Credits Special thanks to for being a partner in crime at this conference and providing all the images 💙 Daniel Banck Want to hear more from me? 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