Facebook software engineer Marc Horowitz introduced Hermes yesterday at the Chain React 2019 conference in Portland, Oregon. Hermes is a new tool for developers to improve app launch performance and make apps more efficient on low-quality smartphones, as is the case with Facebook's apps.
Hermes' default advantage is that developers can target all three mobile platforms with a single codebase; However, as with any cross-platform framework, there are differences in performance, safety and flexibility. GitHub has Hermes for all developers to use. He also has his own Twitter account and login page .
Horowitz stressed that Hermes has reduced apk size by half of its 41 MB and removed a quarter of the app's memory usage.
In other words, with Hermes, developers can enable users to interact with an app faster with fewer obstacles, such as restrictions on low download times and limited memory resources, especially those caused by multiple apps shared on low-quality phones.
And these are exactly the phones Facebook is targeting with Hermes. Compared to the high-quality phones that paid developers usually use.
"As developers, we tend to carry the latest flagship devices. Most users in the world said "no." Frequently used Android devices have less memory and less memory than the latest phones, and much less memory than the desktop. This is especially true outside the United States. The mobile flash is also relatively slow and leads to high I/O latency. ”
"We are not trying to compete in the browser area or server area. Hermes could in theory be for cases of this type of use, which was never our goal.
The records report that Facebook has no plans to push Hermes beyond Nation.js React Native or turn it into the foundation of a Facebook-branded browser. This is because it is optimized for mobile applications and does not offer advantages over other engines in other usage scenarios.
The reason for Hermes' presence, as with Facebook, is to make Native React better. "Hermes allows for more optimization on mobile as developers control the build stack," a Facebook spokesperson told The Register by email. "For example, we implemented a precompilation of byte code to improve performance, and improved garbage collection more efficiently to reduce memory usage."
In a discussion with Hacker News, Microsoft developer Andrew Coates claimed that Hermes internally tested and has a 21.5MB runtime memory effect, compared with 1.4s for the TTI V8, 1.1sn also shows using Hermes in continging with Microsoft Office for Android Domestic Response compared to 30 MB with that V8.
A Facebook spokesperson told The Register that they plan to release benchmark figures next week to support performance claims.