Hermes Engine

With the 0.70 release branch cut, we are excited to announce that @HermesEngine is now the default engine on Android and iOS for 0.70+ Here’s an overview of why we made the switch and all the exciting new changes the community can expect: reactnative.dev/blog/2022/07/0…

With community adoption and feedback, @HermesEngine has flourished. Today, we’d like to share all the progress we’ve made and the case for making Hermes the default engine for React Native. reactnative.dev/blog/2021/10/2…

We have a PR to enable Intl in Hermes. It is some binary increase, but not a lot, about 3% (precise numbers in the PR). github.com/facebook/herme… Should we just enable it, or should we maintain two separate builds with all the associate complexity.

As of yesterday, Hermes supports logical assignment operators: ||=, &&= and ??=. It ended up a fairly small change - the tests are larger than the actual code. github.com/facebook/herme… #javascript

A major milestone: Hermes can now parse the entirety of Facebook's JavaScript codebase, both for web and RN, including all ES6+ features, JSX and Flow type annotations, no Babel or any preprocessing. A single server VM with 24 workers parses 450MB/s. (1 of 3)

For the next Hermes release, we have decreased the installed npm size from 120MB to 18MB! github.com/facebook/herme…

We have recently added ES6 Proxy support to Hermes. Help us test it in your React Native 0.62 based app with npm install hermes-engine@v0.4.2-rc1 and let us know!

Cross-compilation of Hermes to Wasm/Asm.js has finally landed on Github (for many months it was just a local experiment on my laptop)! Now anyone can compile and run Hermes in Node.js or in a browser... A NPM with a packaged Wasm/Asm.js build will follow soon.

We just landed another 5% memory win in Hermes github.com/facebook/herme… . It is a design change that was planned a little more than a year ago. More are coming.

The Hermes JS Engine team has been working hard to improve memory usage. Since July we have decreased our RAM footprint by more than 30% and there are yet more significant savings to come! #hermesengine #javascript #ReactNative

📢 #ReactNative for Windows Milestone 3 is out now! 📢 Milestone 3 includes support for RN version 0.60, native extensions developer story, integration with the high performance Hermes JS engine, E2E test infra and more! microsoft.github.io/react-native-w…

We just landed nullish coalescing and optional chaining in Hermes: github.com/facebook/herme…! Just in time for the TC39 meeting :-) #hermesengine #javascript #ReactNative

@AndrewDurber @nparashuram @ChainReactConf lets see if we can't make this faster, who's with me

Did someone say they wanted to try out @HermesEngine ? Well, there is a build of the @ChainReactConf conference app, running on new engine !!

@kudochien takes a village to build stuff :)

That was all about personal time and lack of sleep.😴 Right now RN is getting better and better and I could really take a rest 😊 Thanks to Facebook and RN community.

Thanks to the release of @HermesEngine, I could have a work life balance right now. It's a good time to talk about the journey to contribute RN this half year. [Thread N]

@KarniejP @kudochien @cnakazawa team of great engineers and partners that helped make this possible. If there is something we can do better, please tell us!

@kudochien @cnakazawa @HermesEngine Thank you for your hard work and dedication to make RN better for us.🎉❤️

@Vardiak #excluded-from-support" target="_blank" rel="nofollow noopener">github.com/facebook/herme…

Now that I'm released, if we were to do some videos with engineers, what types of questions you like answered.

@HermesEngine you are breathtaking!

@NicoAudy we like a bit more targeted approach with 🔥

@HermesEngine 🔥🔥🔥

Hello world, can't wait to show you what i'm capable of. I'm open source too :)

ICYMI (or just a reminder).... @fbOpenSource released Hermes, a JavaScript engine for Android, optimized for @reactnative. Here is the key info: Docs: hermesengine.dev Twitter: @HermesEngine GitHub: github.com/facebook/hermes Talk: youtube.com/watch?v=zEjqDW…