ecosystem.md

11. Architecture Packages

Optional NuGet packages that build production patterns on top of SharpCoreDB. Deep dives: docs/cqrs/README.md · docs/distributed/README.md

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11.1 EventSourcing (SharpCoreDB.EventSourcing)

• Append-only per-stream storage, global ordered feed
• In-memory + persistent stores, snapshot policies
• Stream replay and projections-friendly reads

11.2 Projections (SharpCoreDB.Projections)

• Checkpoint persistence, OpenTelemetry-ready projection metrics
• Built for exactly-once-ish event handling loops
• See docs/internals/PROJECTIONS_OPEN_TELEMETRY_METRICS.md

11.3 CQRS (SharpCoreDB.CQRS)

• Command/handler abstractions, aggregate root
• Outbox with dead-letter workflow for reliable side-effects
• Quick start: docs/cqrs/QUICKSTART.md

public record CreateCustomerCommand(string Name, string Email) : ICommand;

public class CreateCustomerHandler : ICommandHandler<CreateCustomerCommand>
{
    private readonly IDatabase _db;
    public CreateCustomerHandler(IDatabase db) => _db = db;

    public Task<Unit> Handle(CreateCustomerCommand cmd, CancellationToken ct)
    {
        _db.Insert("customers",
            new Dictionary<string, object> { ["name"] = cmd.Name, ["email"] = cmd.Email });
        return Unit.Task;
    }
}

11.4 Distributed (SharpCoreDB.Distributed)

• Multi-master replication with vector clocks
• Distributed transactions (2PC)
• See docs/distributed/README.md and docs/SHARPCOREDB_EMBEDDED_DISTRIBUTED_GUIDE.md

11.5 Functional (SharpCoreDB.Functional)

Option<T>/Fin<T>/Seq<T> functional wrappers across adapters (see Providers). Design rationale: docs/NULLABLE_VS_OPTIONAL_REBUTTAL.md