Currently using, and would use again: Orleans on .NET Core. Orleans is a virtual actor framework, similar to Akka in Scala. For anyone unfamiliar, it's basica

Currently using, and would use again: Orleans on .NET Core. Orleans is a virtual actor framework, similar to Akka in Scala. For anyone unfamiliar, it's basically distributed OOP built into the runtime. You instantiate a User class, and that class instance will exist somewhere in your cluster, but you can access it like a regular class anywhere in code. You could then have a Company class on another node in the cluster, and they can interface seamlessly with each other without any networking code -- just as if they were running on the same machine. Adding capacity is as simple as spinning up more app servers, and because of the way Orleans handles state and garbage collection, you've basically got a distributed cache of all your recently accessed objects, so next time you access them there may not be a need to query the database.