Solid is a very different approach from Sandstorm. I wouldn't call it a successor. Sandstorm gives the user control over both data and compute -- users install

Solid is a very different approach from Sandstorm. I wouldn't call it a successor. Sandstorm gives the user control over both data and compute -- users install apps on their personal server, like installing apps on their phone. Solid focuses on data, specifying standardized storage interfaces and formats, but still expects compute will take place on machines controlled by the developer. I think Solid's approach is unrealistic. Developers want to choose their storage formats and technologies. Even developers that fully support users controlling their data are not going to want to bind their hands to standardized formats that don't support the unique features that the developer wants to implement, or standardized database interfaces that don't meet the app's specific usage model. Also, no developer wants to have to access data across the internet from potentially-unreliable servers on the other side of the world. So I think realistically the code and data have to stay together; the developer has to be able to specify both the code and the data format.