What’s going on with React Native and Messenger? There’s many hot takes, but I’ll stick to my understanding of the facts. A thread so that I don’t have to copy and paste this in replies:

1. The Messenger team published a blog post about the rewrite of their native app. It’s really cool, you should check it out. https://engineering.fb.com/data-infrastructure/messenger/

2. Many readers focused on the app being native. That shouldn’t be a surprise. The app was fully native before the rewrite, too! So it’s a native app — and rewritten to a native app. Turns out, squeezing out the last bits of performance is about more than “being 100% native”!

3. Was this a rewrite from RN? No, Messenger didn’t use React Native at the time it was rewritten.

Again, this is a native app rewritten to a native app. The big change is dropping all of the xplat shared FB infrastructure code (not RN) in favour of a lean core in plain C.

4. Did Messenger ever use RN? Yes, on a few screens in 2017. There was already too much fragmentation in how to build features for Messenger so it didn’t make sense and they removed it.

Removing RN then didn’t “fix” the performance. They decided to rewrite the app from scratch.

5. The focus of the Twitter convos on being native is interesting. Some people even use it to justify hybrid apps with webviews — as if the post supports their argument. But in that sense, hybrid apps are even further from being native! That’s why RN is a great choice for many.

6. But the whole point is that “native” doesn’t guarantee “fast”. The old app was native, AND it was slow. The difference is in how they solved their requirements in a creative way. For example, they don’t write “native views” like everyone else to save size — UI is driven by DB!

7. Facebook’s investment in React Native is as high as ever. The main app has 750+ React Native screens, and it’s used for several standalone apps. It’s not the right tradeoff for Messenger, but this ethos (e.g. lean use of C) inspires a lot of the ongoing React Native work.

8. Facebook engineering culture is all about letting individual teams make choices and decide the tradeoffs for themselves. There’s always multiple competing frameworks and ways of doing things, with different strengths and weaknesses. We trust engineers to make those choices.

9. Anyone shouting about some grand narrative (“use RN for everything” or “RN is dying”) is probably trying to sell you something.

We’re not. We’re only sharing what works for us. Take from it what you will. We hope it’s useful.

10. Beware of tribalism.