Microsoft today launched a preview of PlayFab Multiplayer Servers, a new Azure-based service giving game developers dynamic, on-demand scaling of multiplayer servers.

Microsoft bought Seattle-based PlayFab earlier this year with a view to using it to expand Azure's reach in the gaming world. PlayFab is building all the cloud-based infrastructure needed for today's games: matchmaking (using the same algorithms as Xbox Live to try to group players of similar skill together), leaderboards, server hosting, player identity/profile management, commerce, and so on. Broadly speaking, the intent of PlayFab is to let games developers focus on their games, taking care of the server-side work for them. PlayFab's services are platform agnostic, and Microsoft has preserved this aspect: there are SDKs for Xbox, Windows, PlayStation, Switch, iOS, and Android.

At the time of the purchase, PlayFab ran atop Amazon's AWS. Some parts still do, but others have moved to Microsoft's own Azure. The Multiplayer Server feature, released in preview today, is one of the services on Azure. Microsoft has more Azure data centers in more parts of the world than Amazon or Google, which in turn means that Azure servers should generally be closer to where the players are. This should ensure lower latency and a better gaming experience for games on those servers.

The Multiplayer Server service addresses a common issue for modern gaming: huge spikes in demand (for example, when a much-awaited game launches or when an indie game goes viral) that tend to be relatively short-lived and have a significant regional variation over the course of the day. Developers of AAA titles don't want to size their server capacity so that it can handle these spikes (since over the longer term most of those servers will lie idle anyway), and indie devs with surprise hits on their hands likely don't have the resources to speculatively offer lots of servers anyway.

With PlayFab, developers need only pay for the server resources actually in use, plus a little extra for some standby capacity. For the rest of PlayFab's services, a range of pricing options is available, including a free tier for those just dipping their toes in the space.

Scalable servers on Azure are already being used by a number of AAA titles; Forza Horizon 4, Sea of Thieves, and Tom Clancy's Rainbow Six: Siege are all hosted on Microsoft's cloud.

PlayFab exemplifies Microsoft's new approach to Azure: it's designed to meet developers where they are and to be compatible with the tools and platforms they want. Of course, Microsoft won't complain if a developer wants to use Windows, Visual Studio, and so on and so forth—but the company will also be happy to host Linux applications developed on macOS if that's what a customer prefers.