Very nice! I see this as the next evolution to the phusion's custom init system[0], which was created to solve largely the same problems.
I should be able to take Yelp's dumb-init and add it easily to any linux container I want -- including things such as Alpine[1]
[0] https://github.com/phusion/baseimage-docker/blob/master/imag... [1] https://github.com/gliderlabs/docker-alpine