A way to reduce aok size, juste replace engine V8 by engine hermes

[Fabiyo-90]

Would it be possible to halve the size of the APK by replacing the engine javascrit V8 by hermes of Facebook (https://hermesengine.dev/), we many find that the size of the apk for just one " Hello world !" is quite considerable. I would like to have applications whose apk will be halved.

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[vmutafov]

You could try using Android App Bundles for reducing the APK size.

As of now, I don't think Hermes has many benefits from which NativeScript could benefit. If at some point, we are willing to replace V8 with it, it would need considerable effort and for this to happen - we need a strong theoretical argumentation why Hermes would be better and good benchmarks proving this.

Closing this issue as we do not have plans to invest in Hermes in the near future, feel free to reopen and share your opinion if you think otherwise.

[devinrhode2]

I wonder how app startup times would compare between a react native "hello world" with and without hermes, and in turn how this compares to some "hello world" apps in NativeScript

While it feels like this would be very awesome because Hermes is a surprising new innovation, JIT compilers (like V8 - Hermes is obviously AOT) can be faster in some situations once the compiler has the chance to optimize hot codepaths.

For a fully-fledged app (Mattermost), Hermes reduced time to interactive (TTI) from 4.3 seconds to 2.01 seconds, APK size from 41mb to 22mb, and memory usage from 185mb to 136mb.

Totally not a good benchmark, but as a quick heuristic.. I downloaded some apps from the nativescript showcase on my pixel 3.

Note: I am not registering+logging into these apps, so these numbers aren't reflective of normal usage, where users are already logged in

• California Court Access had about 2 second TTI
• Sennheiser Smart Control also had about a 2 second TTI
• Portable North Pole (PNP?) had about 6 second TTI

I also downloaded Mattermost and got about a 2 second TTI.

So at the outset, surprising to me, Nativescript goes toe-to-toe with React Native+Hermes. Still, I'm sure NativeScript could eek out even more performance by using Hermes.

Cash App from Square has about a 1 second TTI (no idea what the underlying tech is, but I'm thinking it's probably totally native) AirBnb is more around 3 seconds.

[Fabiyo-90]

I really like NativeScript, and I believe like you that NativeScript could greatly improve its capabilities with Hermes, it is true that to date, Hermes is young and not yet very stable and ready for a large-scale production, but see this as an option to reduce only the apk size by half would be a very good thing. Where I am, people mostly complain about the size of the apk.