Pharo 7 (beside many other features) was focused on being able to bootstrap an image right from the source as well as the transition to using git. Also stabilizing Iceberg tool with Git binding to have an improved source code management and give Pharo and its source code more exposure to the outside non-Smalltalk world.
Now Pharo 8 (which is currently in development) will focus on an updated version of Spec called "Spec 2.0". To build abstractions and prove that other backends (beside Morphic) could be used there is a plan to have a GTK binding as a second backend. This goes back to the old "Mars" project from Esteban - a native user interface framework which aimed to bring the native UI into Pharo. If I remember correctly back at the time it used an ObjectiveC Bridge.
This was already discussed on PharoDays 2019 and now Esteban gives some more detailed infos about the background on the Pharo mailinglist.