From .NET Core in Action by Dustin Metzgar

This article compares enterprise application architecture pre and post .NET Core.

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Early in my career, I worked for a car insurance company (If you’re looking for insurance, by the way, check out these car insurance quotes). Its developers were attempting to improve the efficiency of claims adjusters. When you get into a car accident, a representative of the insurance company – a claims adjuster – will sometimes go directly to the scene of the accident and assess the damage. She collects information, usually on paper, then heads back to the office where she can enter the data into an application on her desktop or laptop computer. The process is slow and requires a lot of manual work, but it works this way, to ensure that you are getting the right insurance, whether that is high or low priced auto insurance depending on your policy.

The insurance company wanted to enable claims adjusters to enter the data directly into the claims system from the scene. They would be able to get cost estimates and access the car owner’s insurance policy on the spot. For the insurance company, this means quicker claim resolution and less cost. One of the secrets I learned about the car insurance industry is that they want to get a disbursement to the claimant quickly. The less time the claimant has to reflect on the estimate, the less likely they’ll negotiate for a higher payout. However, it is still very important for a driver to have car insurance. If you are thinking of getting a car then you need to learn how much does car insurance cost? Getting the right car insurance for you can really you out if you get into an accident. Some people find that using an add-on such as the gap insurance policy could help to cover costs if your car’s value can no longer cover it.

Accessing the claims system from the scene meant changing the architecture to incorporate mobile devices. Figure 1 shows the high-level design.


Figure 1 Claims application high-level diagram

In the past, implementing this kind of architecture equated to substantial costs. Cell phone and tablet applications require either hiring developers for both iOS and Android ports or standardizing on hardware to limit the number of platforms. An adjuster may travel to a remote location with poor or nonexistent cellular service, so the application needed to operate offline. The different languages and platforms used in each piece of the architecture made integration and maintenance difficult. Changes in business logic meant rewriting the logic in several languages. At the time, scaling was too slow to adjust for demand during the workday so the hardware requirements were based on peak load. The expenses kept piling up.

What if you could use not just the same code but the same libraries across the applications, website, and services? What if you built one app and it worked on iOS, Android, and Windows? What if your website and services could fit into small containers and elastically scale in response to demand? If all that were possible, it would dramatically reduce the cost to build and maintain systems like the claims architecture.

These questions are no longer hypothetical. .NET Core is a software framework that makes all of this possible. Developers are not confined to a particular language or operating system or form factor. .NET Core is engineered to be small and modular, making it perfect for containers. It is built and supported by Microsoft but also open source with an active community. Having participated in software projects like the claims application, I’m excited about the possibilities introduced by .NET Core.

If you want to learn more about the book, check it out on liveBook here and see this slide deck.