Nerdigy.MediatorA mediator runtime for .NET 10

Dispatch requests, publish notifications, and stream responses through strongly-typed pipelines with expression-compiled caching that eliminates per-call reflection.

Get Started

LLM Quickstart

View Contracts

Request / Response

Send a request, get a typed response. Supports both return-value and void dispatch through a single IMediator interface.

Notification Fan-Out

Publish a notification to every registered handler. Choose sequential execution or parallel dispatch with pluggable publisher strategies.

Async Streaming

Return IAsyncEnumerable responses via CreateStream with dedicated stream handlers, stream pipeline behaviors, and full cancellation propagation.

Pipeline Middleware

Compose pre-processors, pipeline behaviors, and post-processors in registration order. Each behavior wraps the next, following the same middleware pattern you already know.

Exception Recovery

Catch failures with typed exception handlers that can mark exceptions as handled and supply a recovery response. Run side-effects with exception actions before rethrow.

Zero-Config Assembly Scanning

Call AddMediator and point it at your assemblies. Handlers, behaviors, processors, and exception components are discovered and registered automatically.

Minimal Example

csharp

// Define a request and its handler
public sealed record Ping(string Message) : IRequest<string>;

public sealed class PingHandler : IRequestHandler<Ping, string>
{
    public Task<string> Handle(Ping request, CancellationToken cancellationToken)
    {
        return Task.FromResult($"PONG: {request.Message}");
    }
}

csharp

// Register and dispatch
var services = new ServiceCollection();

services.AddMediator(options =>
{
    options.RegisterServicesFromAssemblyContaining<PingHandler>();
});

await using var provider = services.BuildServiceProvider();
var mediator = provider.GetRequiredService<IMediator>();

string response = await mediator.Send(new Ping("hello"));
// response == "PONG: hello"

Three Packages, Clear Boundaries

Package	Purpose
Nerdigy.Mediator.Abstractions	Contracts only. `IMediator`, `ISender`, `IPublisher`, request/notification/stream interfaces, handler interfaces, pipeline and exception interfaces.
Nerdigy.Mediator	Runtime. Dispatchers with expression-compiled caching, pipeline executors, exception processors, notification publishers. No DI framework dependency.
Nerdigy.Mediator.DependencyInjection	Registration. `AddMediator(...)`, assembly scanning, configurable service lifetimes, publisher strategy selection.

Next Steps

LLM Quickstart -- Copy-ready prompts and templates to generate production-ready handlers, behaviors, and streams with minimal iteration.
Decision Matrix -- Pick the right interface and dispatch pattern (Send, Publish, CreateStream) quickly.
Recipe Catalog -- Intent-based prompts for CQRS, domain events, streaming, validation, and exception recovery.
Getting Started -- Install packages, write your first handler, and dispatch a request in under five minutes.
Requests -- Request/response patterns, void requests, and handler conventions.
Pipelines -- Pre-processors, behaviors, post-processors, and execution order.
API Contracts -- Complete interface reference for every public type in the Abstractions package.