Eduard Keilholz

Hi, my name is Eduard Keilholz. I'm a Microsoft developer working at 4DotNet in The Netherlands. I like to speak at conferences about all and nothing, mostly Azure (or other cloud) related topics.
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I received the Microsoft MVP Award for Azure
Eduard Keilholz
HexMaster's Blog
Some thoughts about software development, cloud, azure, ASP.NET Core and maybe a little bit more...

Windows Terminal Context Menu

Just a simple tweak in your registry allows you to change the context menu in Windows Explorer. In this blog post, I show you how to add a 'Windows Terminal here' context menu, opening a new Windows Terminal in the location you're currently at.
2020-10-22

Azure Functions Jwt Validator Binding

It's #ServerlessSeptember so time for some awesome serverless stuff. This time, writing a custom binding. When you want to use a login provider other than Azure AD, you want to validate incoming requests and make sure the caller is authorized. Doing this each and every request with a copied and pasted piece of code is not very convenient. So today we'll be writing a custom Azure Functions binding, validating JWT Tokens for functions with an HTTP Trigger.
2020-09-18

Using Redux in Angular to call an ASP.NET Core Backend

This is a demo project that shows you the power of Redux. This demo project is just an ASP.NET Core 3.1 Web API with an Angular Client app. The client app retrieves data from the API. But this data needs to be filtered. I show the use of Redux to define a data filter and make calls to the backend to refresh the list.
2020-09-11

Building a Boardgame in Azure - Part 5 - Migrations

On of the big disadvantages of using SQL Server in a software system is that you're going to have to deal with migrations. In this post, I will provide a nice solution allowing you to take full control of your database migration and run them from within your CI/CD pipeline.
2020-08-21

Building a Boardgame in Azure - Part 4 - Pipelines

One important factor of agile software development is the OPS part of DevOps. As a developer, you'll probably know how to write code. But do you know how to do OPS? What is this OPS thing? OK, obviously the OPS is an abbreviation of Operations, but still... What do 'operations' mean?
2020-08-18

Building a Boardgame in Azure - Part 3 - Domain Model

'The game' is the heart of this system. It's important to understand how user actions relate to each other and how to maintain a valid state of the game. Now I'm not a DDD expert, but I know Domain Models are a pretty nice way to do validation and propagate changes to 'a system'. So in this blog post, I'll discuss the design of the domain model.
2020-07-03

Building a Boardgame in Azure - Part 2 - Friendships

This is part 2 of my game development blog. It's all about friendships. Keez is a game you play with friends. So when logged in, you need to be able to make friends in order to play the game. At first, the game requires exactly four players, meaning you need three friends in order to create a new game. In case you have no friendships, you can still be someone else's friend and thus be invited to games. This means that friendships are not (yet) bi-directional. Now how do we do this?
2020-07-01

Building a Boardgame in Azure - Part 1 - Planning

This blog post is part one of what I expect is going to be a large series. It's my opportunity to build stuff in the Azure Cloud while ending up with a cool online playable game. It's a board game, played against others. The game is not even half-way finished and I don't know when it's going to be finished. I don't want to spend _all_ my spare time. In this series, I will blog about my progress, how I designed the game from an architectural perspective, and how I solved problems as a (C#) developer.
2020-06-25

A Story About Eventual Consistency

The migration of software to the cloud has begun, a long time ago... In fact, when I started writing software for the cloud somewhere in 2010, I expected us to be a lot further by now. Now, ten years later, cloud services are very mature, fairly cheap compared to on-premises hosting, and very secure. All this, makes me ask why some companies still don't embrace the cloud. One example is scaling. It's almost impossible to host a service on-premises and make it scale as it could in the cloud. Distributed systems leverage this power which makes it almost too easy to build software systems that scale extremely well. But every huge advantage comes with a downside. In this story about eventual consistency, I will show how how to tackle this problem using the Azure Service Bus.
2020-06-19

Feature Toggles in ASP.NET Core

Because we want to keep work items as small as possible, it's not always possible to deliver value when you're using CI/CD, simply because a feature is just not done yet. Yes, you did finish the story and yes you added value. But it's simply not good enough for production yet. More and more stories are completed and merged to the main branch, now what do you do? Release a partially finished feature along with the bug fixes, or wait for the entire feature to complete before you release. The real answer is feature toggles. And once you worked with them, you'll probably never go back.
2020-06-17