There's
Google Stadia,
Microsoft's
Project xCloud, and others, all getting in on the assumed streaming future for how we will all one day play videogames. And now, based on
some code leaks by the fine folks at
SteamDB, there could be something called
Steam Cloud Gaming coming from
Valve.
Which admittedly wouldn't be all that surprising considering Valve's track record of adopting technology and the current - and very solid - state of Steam's digital infrastructure. At the very least this is evidence enough that the company is testing the possibilities of game-streaming over a network, with Steam as the client-side interface. The code references look to be additional options for developers to opt-in to the service.
The framework is sort of already there in Steam with the ability to stream games from one device to another, via the same Steam account, on separate networks. Naturally a Steam Cloud Gaming service would be a pretty large undertaking for Valve - and if code mentions are starting to appear now, then maybe we'll start hearing about Alpha and Beta tests sometime in 2020.