.NET Day Switzerland 2024

This post was started in 2024, but as I attended the .NET Day Switzerland 2025 roughly weeks ago, I remembered, that I never actually finished and published it … until now.

The conference was opened by the organizers with some general information about the conference…

It’s Not Your Dad’s .NET Anymore

…then the word was passed on to Maddy Montaquila a senior product manger at Microsoft.

The keynote showed how much .NET has changed over the past two decades. Especially highlighting the breaking point with the introduction of the iPhone and how it didn’t just affect .NET as a language, but also expand the target platform over time; from Windows to macOS, Linux, Android, and iOS.
The next turning point was, when the user no longer had to pick the wanted runtime before compiling, but that .NET itself takes care of the proper redirecting. As such you end up with a spectrum of supported runtimes. On one side you have the “Websites”, in the middle the “Hybrids” and on the other side the “Native”.

Towards the end of the talk, Maddy got some of her co-workers on stage, so they could, after some awkward and funny notebook switches, provide sneak peeks for their own talks later on at the conference. They showed great camaraderie between each other during these hand-offs and Gerald Versluis even added a slide on-the-fly poking fun at Maddy.

Evolutionary Architecture: The What. The Why. The How.

Next up I visited Maciei Jedrzejewski’s talk on Evolutionary Architecture. It reminded me a bit of last year’s “Architecture Aspects Evolutionary Architecture” talk by Urs Enzler. Maciei showed as part of an example on how you’d go about considering the four steps of evolution:

• Simplicity
• Maintainability
• Growth: Scaling
• Complexity

One of the main message was to choose the architecture based on your current needs and context, and not wishful thinking.
In summary one should start as simple as possible, evolve pragmatically, shift technical decisions, fit architecture to your current needs and remember that businesses change.

Personally, I found the mention of architecture tests (e.g. with ArchUnitNET or NetArchTest) or better said solution structure tests quite interesting, since this can really be useful if you try to ensure that certain layers or projects aren’t being accessed in a wrong way.

100% Unit Test Coverage and beyond

Marc Sallin from Swiss Post intentionally brought a provocative title for his talk. The content of the talk mostly discussed certain fallacies with regards to unit testing, while demonstrating the approaches taken at Swiss Post.

The fallacies looked at were:

• Nirvana fallacy or the danger of false dichotomies
• There’s a threshold
• But not all areas are important
• We just need E2E testing
• Tests are too expensive and we have no time
• Tests shouldn’t be written by devs

Personally, I wasn’t convinced by some of the arguments and my main question, what the precise definition of 100% coverage really means, wasn’t fully answered.

The final part of the talk looked “Beyond 100%” and provided some additional ideas on tooling and checks, such as Coverlet, Sonar, conditional coverage, contract testing, etc.

I was hoping that the talk would address the testability of deep infrastructure code, which is in my opinion the hardest part to “cover”, but I was left without understanding how to approach such code.

It is however very impressive to hear, that there’s no additional QA step for deployments at that one Swiss Post project, because the automated test suite is so solid and covers every corner. This is certainly something to aim for!

Building minimal APIs from scratch

Safia Abdalla, also known as @captainsafia on social media, was one of the three speakers from Microsoft. Her talk was actually a live pair programming session with GitHub Copilot to build up a minimal API implementation from scratch.

It reflected my experience with Copilot in that a lot of LLM suggestions looked good, but were mostly wrong. It felt like the suggestions interrupted the general thought process a lot, taking away the attention of getting the functionality implemented and instead spending time parsing code for correctness.

Of course working on ASP.NET Core at Microsoft, Safia brought a lot of subject knowledge, but it was still quite impressive to see, how quickly some basic API implementation based on HttpListener can be built, including routing and flexible middleware support.

Real-Time Connected Apps with .NET MAUI, Blazor and SignalR

Gerald Versluis, who also works for Microsoft and maintains a popular YouTube channel all about .NET MAUI, talked about SingalR and showcased its usage with MAUI and Blazor.

One thing I learned, is that SignalR implements a fallback chain in case certain technologies aren’t available. By default it will try and use WebSockets, then event source, followed by a forever frame, and if all else fails long polling.

Demystify cloud-native development with .NET Aspire

Having had a sneak peek in the keynote, Maddy Montaquila provided an introduction to .NET Aspire. It’s essentially built on four pillars:

• Observability
• Resiliency
• Scalability
• Manageability

For me personally .NET Aspire’s main selling point is a pretty dashboard that provides actions and insights at a click of a button. To a degree it’s comparable with Portainer, but for .NET applications and more integrated.

Personally, I want to investigate .NET Aspire some more, because I can totally see it fill a gap of running web applications locally and wonder how it would fare on smaller deployments, where you don’t want to spin-up a whole Kubernetes cluster, though you’ll still need a way to manage containers, e.g. with Docker or Podman. I’m interested in how this could replace multi-start setups, where I’d previously would start multiple servers independently.

The Engineering Manager’s Odyssey: Navigating Growth and Evolution in Your Career

Taylor Poindexter held the closing keynote. As an Engineering Manager at Spotify she provided insights on how she manages her teams and what she learned along the way.

Disclaimer: As it has been a while since I’ve heard this talk, I don’t fully remember how my notes line up with the talk itself, so I’ll try to remain a bit more generic and apply it more to my understanding and experience.

Even though I’ve never been a manager, a lot of the presented points rang familiar and true to me.

You often have more impact on people’s life at work, than their spouse.

The quote is to some degree quite obviously true. Spouses usually have little insight into the actual work, where as a good manager should know, whether their people are having an impact and where they still need some help. Except this unfortunately isn’t always as obvious to many managers.

One of the best things to achieve as a manager / leader is to create a space of psychological safety, meaning people should feel safe to talk not just about the good things, but also bring up hard topics, without having to fear bad / malicious reactions from you as a manager or anyone else on the team. This will make it easier to receive honest feedback from people and thus allow for a greater influence towards improvements.

However, the other side of a being a manager is to find your own happiness in the work and to not forget your own bread and butter of the work. One can fight chaotic times by managing the calendar well and blocking off time to strategize.

Finally, to find out whether you’re going towards success or not, you may have a few indicators:

• Meeting the deadlines
• VP / other managers notice the work
• Team is happy / pushing

The best outcomes I’ve experienced is, when people feel safe enough to address any issue and don’t secretly spin in circles disliking some situation or worse, people.

Worth It?

As a single day .NET conference in the middle of Zürich with reasonable pricing, organized by volunteers and just investing the money into the location and travel & accommodation for the speakers, I can recommend it highly!

Do remember to book tickets early enough, as they regularly sell out the whole conference.