на hackernews аналитики уже «поработали»
The repo at https://fuchsia.googlesource.com reveals a rather interesting UI story for this new operating system.
It seems like the intention is to use Flutter  as the UI layer. Flutter uses the Dart language, so there's a Dart environment included in Fuchsia too.
For rendering, Fuchsia includes a project called Escher  which is described as a physically based renderer that supports soft shadows, light diffusion and other advanced effects. Looking at the source code, Escher is designed to use either OpenGL or Vulkan as the underlying graphics API. (There's an iOS example project included in Escher's source tree. Would be interesting to build that.)
It's not immediately obvious why a lightweight operating system would need a renderer that can do realtime soft shadows and light effects...! But I think the idea here is to build an UI layer that's designed from scratch for Google's Material design language. Shadows and subtle color reflections are a major part of that «layered paper» aesthetic.
So, the stack seems to be: Dart is the language for GUI apps, Flutter provides the widgets, and Escher renders the layers.
так же есть теории что это следующий Android
I'm calling it now: this is for augmented reality displays and similar. You want an RTOS for loss and predictable latency. And current GUIs aren't really suited to 3D environments you can walk around inside.
This is Google's next Android, with a low latency rendering pipeline for the next generation of mobile devices.