Does it support OStatus?
It seems that Microblog is a mixture of Feeds and the Indieweb, namely the Micropub API which originated there:
http://help.micro.blog/2017/api-posting/
Btw: Isn't ActivityPub the new OStatus?
Might also be worth pointing out that Micropub is a W3C Recommendation [1], and I think MicroPub and ActivityPub are meant to work together [2].
[1] https://micro.blog/about