I Built My Own CQRS Library for .NET — Here's Why

Varun Kumar — Sat, 19 Sep 2026 18:56:16 +0000

I Built My Own CQRS Library for .NET — Here's Why

If you've worked on large .NET applications, you've probably encountered CQRS.

The basic idea is straightforward:

Commands → Change State
Queries  → Read State

But once an application grows, the infrastructure around CQRS can become repetitive.

You need request abstractions, handlers, dispatching, pipeline processing, validation, dependency injection, and other cross-cutting concerns.

That led me to build MediCore.

What is MediCore?

MediCore is a lightweight CQRS infrastructure library for .NET applications.

The goal isn't to force a particular architecture.

Instead, MediCore provides reusable infrastructure that can fit into architectures such as Clean Architecture.

The Problem

A typical application may contain:

Controller
    ↓
Command
    ↓
Handler
    ↓
Validation
    ↓
Business Logic
    ↓
Repository

When this infrastructure is implemented repeatedly across different applications, there is an opportunity to make the common parts reusable.

The Idea Behind MediCore

MediCore focuses on the application layer.

A simplified flow looks like:

              Request
                 │
                 ↓
          ┌─────────────┐
          │   MediCore  │
          └──────┬──────┘
                 ↓
          Pipeline Behaviors
                 │
                 ↓
              Handler
                 │
                 ↓
          Business Logic

This allows cross-cutting concerns to be handled independently from the core business logic.

CQRS

MediCore follows the CQRS approach:

             Application
                  │
        ┌─────────┴─────────┐
        ↓                   ↓
     Command              Query
        ↓                   ↓
     Handler              Handler
        ↓                   ↓
      Write                Read

Commands and queries have different responsibilities.

Commands modify state.

Queries retrieve state.

This separation can make application code easier to organize as the system grows.

Pipeline Processing

One of the important ideas is pipeline-based processing.

For example:

Request
   ↓
Validation
   ↓
Authorization
   ↓
Logging
   ↓
Transaction
   ↓
Handler

Instead of placing these concerns inside every handler, they can be handled through pipeline processing.

Installation

MediCore can be installed using:

dotnet add package MediCore

Who is it for?

MediCore is intended for developers who:

Build .NET applications using CQRS
Follow Clean Architecture
Want reusable CQRS infrastructure
Want to separate commands and queries
Need extensible pipeline processing

What's Next?

The project is still evolving.

I'm working on:

Better documentation
More examples
Additional pipeline behaviors
Performance benchmarks
Community feedback
More advanced CQRS scenarios

Try It

If you're interested in CQRS and .NET, give MediCore a try.

The project is available through NuGet and GitHub.

I'd love to hear feedback, suggestions, and ideas from the .NET community.

Building software is not only about writing code. Sometimes it's about turning repeated problems into reusable solutions.

That's the idea behind MediCore.

DEV Community: Varun Kumar

I Built My Own CQRS Library for .NET — Here's Why

I Built My Own CQRS Library for .NET — Here's Why

What is MediCore?

The Problem

The Idea Behind MediCore

CQRS

Pipeline Processing

Installation

Who is it for?

What's Next?

Try It