Sony Mobile may not be making as much as other OEMs like Samsung, but they have worked with the open source community quite a bit. In the Android community, we have seen this in a number of ways with the company's Open Devices program being one of their popular contributions. Sony ends up adding a number of their devices to this program with the which can really help boost the developer community support for said devices. This week it has been announced that Sony is officially adding the Xperia XZ2 and the Xperia XZ3 to the program.
For those who are unaware, the Sony Open Devices program is something the company uses to give back to the open source community. Sadly, we don't see every new Sony smartphone added to the program, but the ones that do get selected are provided with vanilla Android Open Source Project (AOSP) device configurations on GitHub. For some devices, all it takes is the open source code for the kernel and that kickstarts the community developer support. This helps but that isn't all the work that goes into creating a custom ROM.
So with Sony's Open Devices program, the company provides the AOSP code for select devices and publishes them on GitHub. The addition of the Xperia XZ2 and Xperia XZ3 also means they come with build guides (for both the AOSP build, the kernel compilation) and other resources, including how to access UART ports. Not only can this make custom ROMs better for those devices, but it also gives Sony a tool to verify submissions from the developer community who are wanting to contribute as well.