cratis-engineering-csharp-conventions

Use records for events, commands, and DTOs, primary constructors for classes, file-scoped namespaces, var for locals, and is null checks. Name types after the domain without technical postfixes like Service, Manager, or Handler, and document every public member with multiline XML comments.

Define a domain exception deriving from Exception without the Exception suffix, such as AuthorNotFound instead of AuthorNotFoundException. Always supply a meaningful message and document it with an XML summary starting with "The exception that is thrown when".

Use [Singleton] only for process-wide services holding no tenant-, user-, or request-bound state. A singleton capturing a scoped collaborator silently binds to the root scope's default namespace forever; inject IServiceScopeFactory and open a scope per unit of work instead.

Use IInstancesOf<T> from Cratis.Types to enumerate implementations of an abstraction, since the framework discovers them by convention. IEnumerable<T> only works when every implementation is hand-registered, which defeats convention-based discovery.

No, this skill covers C# only. TypeScript and React questions, specification files using the Establish/Because/should_ pattern, and product API behavior decisions are routed to their own focused workflows.