What is Microsoft's MeTAOS?

Some hardworking Microsoft sleuths have been unearthing some new codenames and leads this weekend. Thanks to @h0x0d (The Walking Cat) and Tero Alhonen (@terhoalhonen) we have a bit of information about Microsoft's "MeTAOS" and "Taos." Microsoft already has a "productivity cloud" in place with its Microsoft 365/Office 365 set of offerings. Underpinning Office 365 is a layer called the "substrate," which is Microsoft's customer data platform. Microsoft is now endeavoring to build a large-scale distributed platform, or foundation, which will sit on top of SharePoint, the Office 365 substrate, Azure, Microsoft's machine-learning infrastructure and more.