Scalable Webhooks in .NET – From Scratch to Scale

Build real-time notification systems in .NET that grow with your app. Learn webhooks fundamentals, design robust ASP.NET Core architecture, and implement advanced scaling with messaging brokers.

Course Overview

Imagine your .NET application could instantly notify other services whenever something important happens – no polling or manual checks needed. Scalable Webhooks in .NET is a self-paced course that shows you how to build a complete webhook delivery system from the ground up and scale it to handle production-level demand. You’ll start with the basics of what webhooks are and why they’re powerful, then dive into designing and coding a fully functional webhook system in ASP.NET Core, step by step. Along the way, you’ll follow real-world scenarios (like an e-commerce site sending order events to external partners) to make the concepts concrete and practical.

Whether you’re a newcomer to backend development or an experienced .NET engineer, this course guides you through both beginner and advanced topics. We begin by demystifying webhooks and creating a simple end-to-end implementation from scratch. As the course progresses, you’ll learn how to avoid common pitfalls in naive webhook setups – for example, sending webhooks synchronously on the main thread to multiple subscribers can bog down your app as traffic grows. To solve this, we introduce an asynchronous event-driven approach using background processing. You’ll implement an in-memory event bus that decouples webhook sending from the main application flow, so your users don’t experience delays even when multiple webhooks fire at once. We then push beyond the basics: to truly scale out and improve reliability, you’ll integrate a message broker (RabbitMQ via MassTransit) to offload and distribute the work of delivering webhooks. By the end, you will have a production-ready architecture that can handle high volumes of events, with robust retry policies and fault tolerance built-in. Throughout the course, every concept is explained in clear, accessible terms (with plenty of code examples), so it’s beginner-friendly while still providing deep insights and performance tuning tips for seasoned developers.

What You’ll Learn (Key Modules)

1. Building a Webhooks System in .NET from Scratch: Learn webhook fundamentals and create a basic webhook setup step by step. You’ll build an ASP.NET Core Web API that lets clients subscribe to events with a callback URL, and implement the logic to send HTTP POST notifications to those URLs whenever an event is triggered. This module covers the end-to-end flow – from defining data models for subscriptions, to handling incoming subscription requests, to dispatching event payloads. You’ll also tackle essential basics like queuing retry attempts for failed webhook deliveries and securing your webhooks with secret tokens or signatures. It’s a hands-on introduction that lays the groundwork for everything that follows.
2. Webhooks Architecture in ASP.NET Core: Design a robust, scalable architecture for webhook systems using best practices of ASP.NET Core. In this module, you’ll structure your application for maintainability and flexibility – separating concerns between the core application and the webhook delivery mechanism. Key topics include setting up a subscription storage (using a database or in-memory store) to keep track of client endpoints, building a Webhook Controller or endpoint to manage subscriptions and receive event triggers, and using dependency injection to manage services like an HTTP client factory for sending requests. We’ll also discuss security practices, such as validating webhook payloads and using HTTPS and authentication for webhook endpoints, ensuring your implementation is secure from unauthorized calls. By the end of this module, you’ll understand how all parts of the system fit together within the ASP.NET Core framework, following an enterprise-grade design that’s easy to extend.
3. Implementing a Webhooks Event Bus in .NET: Here, you’ll enhance the basic system by introducing an event bus to decouple event processing from HTTP request handling. Instead of sending webhook HTTP calls directly during an event (which can slow down your app), you will implement an in-memory queue (or channel) and a background worker to handle webhook delivery asynchronously. This means when an event (like “Order Placed”) occurs, your application will publish a message to the event bus and immediately return control to the main thread. A dedicated background service will subscribe to the event bus, pick up the event message, and take care of calling all subscriber URLs in the background. You’ll learn how to use .NET’s built-in channel or queue constructs and the BackgroundService pattern to process events in parallel or safely handle them one-by-one. This module dramatically improves performance and user experience, as the main application no longer waits for all webhooks to be sent. You’ll see how this design fixes the bottleneck of the naive approach (no more blocking the user request while webhooks send!), and sets the stage for scaling out across multiple servers.
4. Scaling Webhook Delivery with a Message Broker: In this module, you’ll take your webhook system to the next level by integrating an external message broker (such as RabbitMQ) into your architecture. An in-memory event bus is great on a single server, but to scale beyond one instance (and to avoid losing messages if the app crashes), you need a more durable, distributed solution. You’ll learn how to publish event messages to a message broker so that multiple consumer services can handle webhook delivery in parallel, enabling virtually unlimited scalability. We’ll set up RabbitMQ (a popular open-source message queue) in a .NET environment and modify the event bus to use it as the backbone for our webhook events. You will walk through creating message definitions, configuring publish/subscribe exchanges, and ensuring persistence of messages. Crucially, this module demonstrates how using a broker allows you to horizontally scale: you can run multiple webhook sender services consuming from the queue, share load between servers, and reliably buffer burst traffic. By the end, your webhook system will be able to handle high volumes of events and subscribers without breaking a sweat, and it will be resilient to outages (thanks to the durable queue preserving events).
5. Scaling a .NET Webhooks System with MassTransit and RabbitMQ: In the final advanced module, you’ll leverage the MassTransit library to streamline your integration with RabbitMQ and implement a truly enterprise-grade solution. MassTransit is a powerful .NET library that abstracts message brokers and implements the boilerplate for you. You’ll learn how to configure MassTransit in your ASP.NET Core project to connect to RabbitMQ, declare message contracts and consumers, and let MassTransit handle the heavy lifting of wiring everything up. This module covers setting up producers and consumers using MassTransit’s fluent configuration, and shows how MassTransit automatically handles concerns like retry policies, error queues, and message serialization with minimal extra code. You will implement a Webhook Dispatched event message and a corresponding consumer that sends out the HTTP requests to subscribers. With MassTransit, features like automatic retries on failure are often enabled out-of-the-box, making your webhook delivery more robust (e.g. it can automatically requeue failed deliveries for another try). We’ll also explore using MassTransit’s monitoring and diagnostics to observe your message flow. By using MassTransit on top of RabbitMQ, you get the benefits of a proven framework: your scalable webhook system will be easier to maintain and extend, and you can swap underlying transports (RabbitMQ, Azure Service Bus, etc.) with minimal code changes. This final module solidifies your understanding of building cloud-ready, distributed systems in .NET – you’ll be confident in applying these patterns to any event-driven architecture beyond just webhooks.

Who Should Take This Course?

This course is designed for developers of all levels who want to build real-time features and learn scalable architecture in .NET:

• Beginners: If you’re relatively new to .NET or backend development, this course will guide you gently through the foundational concepts of webhooks and API integration. You’ll get a clear understanding of how webhooks work and plenty of step-by-step coding practice. (Basic familiarity with C# and ASP.NET Core will help, but you don’t need expertise to start.)
• Intermediate/Advanced Developers: If you already have experience with .NET, this course will take you to the next level in architecture and performance. You’ll gain hands-on experience with asynchronous programming, background services, and messaging frameworks (RabbitMQ/MassTransit) – invaluable skills for designing high-performance, distributed systems. We’ll also share tips and best practices drawn from real-world scenarios, which can help you in scaling any enterprise application.
• Software Architects & Tech Leads: The patterns and solutions covered (event-driven design, message-based scaling, reliability considerations) are useful for anyone designing systems that need to handle growth. This course provides a practical case study in evolving a simple application into a robust, scalable infrastructure. It’s a great way to get your team up to speed on modern .NET architecture for event-based communications.

In short, if you want to integrate real-time notifications into your apps, replace inefficient polling with efficient push mechanisms, or simply understand how to build a maintainable distributed system in .NET – this course is for you.

What’s Included in the Course

• 8+ Hours of Video Lessons: Engage with comprehensive video tutorials (recorded in HD) that walk you through each concept and coding task. Watch the instructor build the webhook system in real time, with clear explanations at every step. You can follow along at your own pace, pause, rewind, and code with the videos.
• Written Guides & Notes: Each module comes with detailed written documentation and reference notes. These written materials reinforce the video content – perfect for quick review or for those who learn better by reading. The guides include diagrams of the webhook architecture, important code excerpts, and additional commentary on “why” we do things a certain way.
• Complete Source Code & Examples: You’ll get the full source code for the project, organized by module. This includes the initial simple webhook implementation and the final scaled-out version with MassTransit and RabbitMQ. You can download and run the projects on your own machine. The code is well-commented and serves as a great starting point or template for implementing webhooks in your own applications.
• Self-Paced, Lifetime Access: The course is entirely self-paced – there are no deadlines or schedules. You get lifetime access to all the content, so you can learn on your own timetable and revisit the material anytime. Plus, any future updates or additions to the course will be available to you at no extra cost.
• Q&A Support: (If applicable) Join a community of fellow students. You’ll have access to a Q&A section or community forum where you can ask questions, share progress, and get help from the instructor and peers. Learning is better together – get your doubts cleared and see how others are innovating with webhooks!