HMD releases kernel sources for the Nokia 8, Nokia 6, and Nokia 1

HMD finally released the kernel source of its Nokia 8, Nokia 6 2017, and Nokia 1, allowing developers to start the development of custom ROMs for the device. 

HMD Officially does not permit the Nokia devices to be bootloader-unlocked. But there's an Unofficial way which can be found on XDA.

A developer at XDA has found a way of unlocking bootloaders on the Nokia 2, Nokia 5, Nokia 6, and Nokia 8. While testers have confirmed the fact that it does work, the methods involved may not be the safest.

The kernel sources are available in the tar.gz file extension. If you're interested in developing a custom ROM for Nokia devices, the go ahead to Nokia's Website and download the kernel sources and set it up in the Android Kitchen.