--- title: "React Native 0.64 With Hermes for iOS" description: "Discover how Hermes boosts React Native performance on iOS and macOS, with insights into AOT, bytecode precompilation, and the future of Hermes support." url: https://www.callstack.com/podcasts/react-native-0-64-with-hermes-for-ios-ep-5 updated: 2026-10-24T08:39:43.214Z --- # React Native 0.64 With Hermes for iOS Discover how Hermes boosts React Native performance on iOS and macOS, with insights into AOT, bytecode precompilation, and the future of Hermes support. _Guest: Eloy Duran, Principal Architect @ Microsoft · Host: Mike Grabowski, CEO & Founder @ Callstack · Published 2021-05-11 · Duration 01:04:03 · Category: Hermes_ Listen: [YouTube](https://youtu.be/lbdIKZrOUMc) · [Spotify](https://open.spotify.com/episode/5KwIhT1rcez903dedjAgfr) · [Apple Podcasts](https://podcasts.apple.com/dk/podcast/react-native-show-podcast-episode-5-react-native-0/id1525543072?i=1000521498436) · [SoundCloud](https://soundcloud.com/user-985069846/the-react-native-show-podcast-episode-5-react-native-064-with-hermes-for-ios) The episode #5 is all about Hermes: Mike and his guests discuss its technical features, biggest selling points, and possible future developments. They start with the basics though, so at the beginning, you will find out what Hermes is and what it actually does. ## Bringing the Hermes engine to iOS - Hermes improvements to React Native apps in terms of three metrics: Time To Interactive (TTI), Application Size (APK), Memory consumption - The “magic” behind Hermes - “Bytecode Precompilation” a.k.a. AOT - The difference between AOT and JIT - JIT JS engine pipeline vs Hermes pipeline - The Hermes roadmap and plans for further improvements ## Hermes support for MacOS In the last part the focus shifts towards bringing Hermes to React Native MacOS. Since Microsoft recently added support for Hermes on MacOS, Elloy describes the process behind it, mentions the solutions considered prior to Hermes, and takes a quick look into the future of Hermes support for MacOS. - What was the motivation behind adding support for Hermes on MacOS? Any plans for RN Windows? - Were there any attempts to bring Chakra to run on macOS, to say, provide more unified experience across desktop platforms? - On Apple devices, unlike Android ones, there were always less of performance and memory related issues when it comes to running React Native applications. What would be the selling point of Hermes in such a case? This and much more you can find in the Episode #5. Pick your favorite platform and check it out! Insights ## Learn more about Hermes Here's everything we published recently on this topic. [View all](https://www.callstack.com/insights) - [Why You Don’t Have to Minify JavaScript Code in React Native Apps](https://www.callstack.com/blog/why-you-dont-have-to-minify-javascript-code-in-react-native-apps) (Dec 18 · Article): React Native skips JavaScript minification in production because Hermes handles dead code elimination at the bytecode level. Here’s how and why it works. - [From Static Hermes to Hermes V1: The Road to Default](https://www.callstack.com/podcasts/from-static-hermes-to-hermes-v1-the-road-to-default) (Dec 4 · Podcast): Nicola Corti (Meta) explains the evolution of Static Hermes into Hermes V1, the performance boosts it ships, and the (experimental) path to making it the new default engine. - [Hermes V1: What It Is, What It Isn’t, and What’s Next](https://www.callstack.com/events/hermes-v1-what-it-is-what-it-isnt-and-whats-next) (Nov 6 · Live Stream): Łukasz Chludziński, Szymon Chmal, and Matt Hargett unpack Hermes V1, covering what’s new, what’s changing, and what’s ahead for React Native performance. - [How to Optimize Your Android App Startup Time With Hermes](https://www.callstack.com/blog/optimize-android-app-startup-time-with-hermes) (Dec 4 · Article): Learn how to achieve better performance and optimize Android app startup time with Hermes. - [Technical Guide, Part 2: Integrating Hermes With React Native](https://www.callstack.com/blog/technical-guide-integrating-hermes-with-react-native) (Jun 14 · Article): Interested in the Hermes engine? Check the second part of our expert guide to find out how to integrate Hermes with React Native. - [Technical Guide, Part 1: Compiling Hermes for Apple Platforms](https://www.callstack.com/blog/technical-guide-compiling-hermes-for-apple-platforms) (May 26 · Article): Want to use Hermes in your React Native app on iOS? Find out how to compile Hermes for Apple platforms. Check the first part of our expert technical guide. - [Hermes Performance on iOS](https://www.callstack.com/blog/hermes-performance-on-ios) (Apr 21 · Article): Wondering how the Hermes engine performs on iOS? We tested it on a React Native mobile app. Check the results and see how it compares to JSC. - [Bringing Hermes to iOS in React Native 0.64](https://www.callstack.com/blog/bringing-hermes-to-ios-in-react-native) (Apr 14 · Article): Hermes is now available for iOS as well. Find out more about this JS engine - check the first part of our series on bringing Hermes to iOS.