called Software for Open Networking in the Cloud or SONiC.
SONiC is a collection of networking software components required to have a fully functional L3 device that can be agnostic of any particular Linux distribution. Today SONiC runs on Debian and available on Github.
No support from Microsoft, they intend to keep SONiC relevant, reliable and stable. The rest depend on a community or your development resources.
A major requirement for the switching silicon - to be SAI-compatible.
A detailed post from Mark Russinovich is here.