I think you mean using Yocto to build a base snap? Similarly, to Ubuntu Core, Freedesktop runtime (Base runtime freedesktop-sdk-runtime-19-08) and (Fedora 29 base snap, demoed last year).
If so, feel free to ping me. I’d be interested in helping out. Might even push some patches in time for 2.8 release.
Building a bootable base on Yocto is something completely different though.