Jason Goldberg is Founder and CEO at Airstack,OST, makers of the Pepo app. OpenST. MosaicDao. Past: Hem, Fab, XING, Social Median. OST is a full-stack technology platform that enables mainstream companies to easily integrate blockchain into their apps and manage their blockchain economies. Following 2 years of development, OST is going to market in Q2 2019 with clients who reach more than 400 million MAUs. OST intends to be the company that delivers real blockchain use cases in 2019.