These are my notes on the recent panel in the Facebook developer conference. Watch the original video . React Native F8 2018 here Where is it used — Marketplace, Jobs, Safety Check etc Facebook Skype — Skype app TaskRabbit — Tasker app Postlight — Audubon Bird Guide CondeNast — Vogue iOS app Code reuse between multiple platforms Facebook: ~93% Skype: 85–90% TaskRabbit: ~86% Postlight: 90–95% Why was it chosen Facebook Platform specific codebases result in Developers hitting different snags Each platform moving in different speeds Getting out of sync Doing same things twice Polish/optimization doesn’t get done uniformly in both platforms Skype Platforms: iOS, Android, Windows, Mac, Linux — Using ReactNative or Electron+React Before ReactNative 7 devs and 7 product owners for each platform across multiple timezones Main issue was communication between different platforms in different timezones After ReactNative Moved from platform specific teams to feature squads that focus on delivering features across different platforms Feature squads reduce the communication challenges and improve development velocity Reduces implementation discrepancies in different platforms Got transferable knowledge as all the teams speak the same language Easy to ramp up squads for new features and ramp down squads for other features Ramp up time is almost zero as there’s a single language used Lost good developers Focus on hiring generalists React — Same UI description language and layout semantics for all platforms React — Everything is encapsulated in a component as opposed to code scattered across different layers Uses ReactXP TaskRabbit Before ReactNative 3 devs on each mobile platform After ReactNative 2 person team moving faster than the 6 person team Business logic lives in a single place and bugs gets fixed for both platforms at same time Helps in hiring Postlight Postlight has React (web) experience 1.5 devs, completed before deadline and under budget CondeNast CondeNast is a JS shop, so using ReactNative to leverage that experience Why replace Swift with JS? Declarative layouts with JSX Writing layouts in Swift is hard Iterate very rapidly Lower the barrier to create layouts Frees developers from working on “pixel pushing” Gives them time to focus on harder and interesting things Lessons learned Postlight Was able to do performance tuning for low-end devices targetting Indian market ReactNative is not prescriptive and makes it possible to drop out of ReactNative and use native modules when needed Ran into performance issues when you don’t expect the same with native modules (long scrolling lists etc) CondeNast Being early adopter Going through multiple ReactNative version bumps is tough Better suited for apps that are under active development as batching several updates at once is painful Originally published in sheshbabu.com
