Hi! I'm Clemens Schotte,

Cloud & Apps specialist, Developer, Technical Evangelist, and public speaker.

WiFi Calling

Modern buildings are well isolated, which isn’t good if you are making a mobile phone call. Outside your house or office, the cellular signal is perfect, but inside it is another story, dropped calls, low-quality sound, etc. Even when your carrier has high coverage, there are situations inside buildings that prevent you from making a call. Most mobile network providers (carriers) provide a solution for this, called WiFi Calling. By utilizing the existing WiFi network in your home or office, the mobile phone can make calls.

Free and Built-In TLS/SSL certificates in Azure

Today, when a website does not have an SSL/TSL certificate, web browsers give you a warning not secure. This warning not only scares people but also gives you a disadvantage in search engine ranking. On Azure, web sites have a default https-enabled URL, like https://sitename.azurewebsites.net/, but when you have a vanity domain configured, you are missing this secure connection. Luckily there are some free SSL/TLS certificate options to explore. Let’s Encrypt Wait, there is Let’s Encrypt, its free!

Upgrading my Amiga 1200 in the year 2020

I learned all my basic computer and programming skills on Commodore computers, like the C64, Amiga 500, and 1200. Twenty-eight years ago, I upgraded my Amiga 1200 with a faster processor (Motorola 68030) and extra memory (4 megabytes). I also added an FPU (Motorola 68882), a realtime clock, and an internal hard disk (120 megabytes), which is still working correctly in 2020 (wow). At that time, this was a fast Amiga.

My solar energy and Tesla Powerwall 2 setup

Saving the planet a little bit and trying out new technology is cool, and in the end, it will save me also some money. When building my house last year, I invested in solar energy. The sun delivers me free electricity during the day, especially around noon, but I use it mostly at the end of the day and at the beginning of the evening. Most of my solar energy goes to the public energy grid, and I need to bay it back in the evening.

Calculate the availability and SLA for your Azure solution

Microsoft provides for most Azure services an Service Level Agreements (SLA), where you can find the availability for that services. The availability has a rage from 99.9% to 100% or no range at all (for some free services). “We guarantee that 99.95% of the time, the Azure … Service will successfully receive and respond to …” The SLA describes Microsoft’s commitments for uptime and connectivity. It is also somewhat guaranteed, i.

Using Visual Studio Code with PHP and Xdebug

This post describes how to set up, run, and debug PHP code with Visual Studio Code running on Windows. What do we need? Compared to some other popular programming languages for the Web, PHP is missing some tools, so I created a shopping list to make the experience more complete. Basically what we need is: the PHP runtime itself, a modern code editor with syntax highlighting, a debugger connected to our code editor, and a (development) webserver.


CaveRace is a classic maze-based video game I developed back in 1997 with some other students. Inspired on a game, I played on my Commodore Amiga, called Dyna Blaster (Bomberman). Forest level Winter level Winter level Download You can download the 16-bit MS-DOS version of CaveRace (version 1.2) here. Story On the planed Eldora, there are miners collecting gold and diamonds.

Generate PDF files with asp.net core on Azure

There are many libraries and services to generate PDF files for asp.net core web applications. There are excellent commercial solutions out there, but if you need a free solution, it gets harder. Some libraries are hard to use, or others are limited in functionality. I need a free, easy to use, and quick solution to generate PDF files on an Azure Web App. Can a View retrun a PDF? What I need is a View that returns a PDF and not HTML what it usually does.