SpacetimeDB

What SpacetimeDB is

SpacetimeDB is a backend platform for applications that need a relational database, server logic, authentication, deployment, and live data updates in one system. Its database supports strongly serializable ACID transactions, and it automatically sends changes to clients subscribed to data. Server modules run within the database and can be written in Rust, C#, TypeScript, or C++; client support includes TypeScript and JavaScript, C++ with Unreal Engine, C# with Unity, and Rust. For hosting, Maincloud offers a managed serverless service that can scale to zero and charges according to usage. Teams can also run SpacetimeDB on their own infrastructure, on Windows, macOS, or Linux, or with a Docker command. Authentication uses OpenID Connect identity tokens and works with providers such as Auth0, Firebase, Clerk, Google, GitHub, and Facebook. SpacetimeAuth is a beta option for managing authentication without an external service or hosting server. Clockwork Labs says it first built Spacetime for BitCraft Online, its shared-world MMORPG, which still runs on the platform. Maincloud has a free plan and paid plans starting at $25 a month.

Who it suits

SpacetimeDB suits developers building applications that need a relational database and synchronized client data, including multiplayer games. It offers a choice of managed Maincloud hosting or self-hosting, with server modules and client support across several languages.

Limits

Maincloud Free includes 2,500 TeV credit per month, up to 20 projects, five databases per project, and five users per project. It also limits each database to five collaborators and includes one hour of metrics history. Maincloud Pro costs $25 a month and includes 100,000 TeV credit monthly; additional usage is charged at 2,592 TeV per dollar.

Getting started

1. Open the SpacetimeDB website.
2. Choose Maincloud or follow the documentation to self-host on your infrastructure.
3. For a local instance, use Windows, macOS, or Linux, or run the provided Docker command.
4. Write server modules in Rust, C#, TypeScript, or C++.
5. Connect a supported client and configure OpenID Connect authentication if needed.

Verdict

Choose SpacetimeDB if your application needs database transactions, embedded server logic, and automatic synchronization, particularly for multiplayer networking. Maincloud's free plan has monthly credit and collaboration limits, while paid plans start at $25 a month; teams wanting SpacetimeAuth should account for its beta status.