Coffee-Driven Development

Whole Team Collaboration: Navigating the seven C's

Fri, 12 Dec 2025 00:00:00 +0100

On November 27 and 28, I went to the XP Days Benelux conference. This blog post is a short recap of all the things I learned.

In this third post in the XP Days series, I’m sharing my notes and reflections from the session “Whole Team Collaboration: Navigating the Seven C’s” by Per Beining. There are many ways of working together, and many ways of not really working together. By introducing the Seven C’s (spoiler: there are actually eight), Per offered a simple but powerful lens to help teams recognise how they currently collaborate and what they might change to truly work together.

The goal of the session was to build awareness: understand the difference between merely working side by side and genuinely collaborating, and learn how to spot which “C” your team is currently navigating—so you can steer toward the harbour you actually want to reach.

DUO Portfolio Game

Thu, 11 Dec 2025 00:00:00 +0100

On November 27 and 28, I went to the XP Days Benelux conference. This blog post is a short recap of all the things I learned.

In this second post, I’m sharing my notes and reflections from the session “DUO Portfolio Game” by Jan-Willem Zijlstra, Jeroen Smit, and Willem Kleinenberg. The session introduced a game they developed to spark conversations about culture, collaboration, and ways of working. Through several rounds, participants experienced firsthand how different strategies for distributing work across teams can shape flow, ownership, and alignment.

The goal of the session was clear: explore how teams might organize and collaborate more effectively, and discover what happens when you shift constraints, responsibilities, or communication paths.

So long, and thanks for all the fish - The farewell tour

Wed, 03 Dec 2025 00:00:00 +0100

On November 27 and 28, I went to the XP Days Benelux conference. This blog post is a short recap of all the things I learned.

In this first post, I’m sharing my notes and reflections from the session “So Long, and thanks for all the fish - The farewell tour" by Ron Eringa, Paul Kuijten, and Dajo Breddels. The session explored the question of whether the Agile movement has run its course: been there, done that, got the T-shirt. With the Agile label losing some of its shine, the facilitators invited us to properly say goodbye to what no longer serves us, and to salvage the practices and principles still worth keeping.

The goal of the session was simple but important: take stock. Is Agile dead? And if not, how do we move forward?

An Astronaut's Guide to Life on Earth

Wed, 28 May 2025 00:00:00 +0200

Colonel Chris Hadfield has spent decades training as an astronaut and has logged nearly 4000 hours in space. During this time he has broken into a Space Station with a Swiss army knife, disposed of a live snake while piloting a plane, and been temporarily blinded while clinging to the exterior of an orbiting spacecraft. The secret to Col. Hadfield’s success-and survival-is an unconventional philosophy he learned at NASA: prepare for the worst-and enjoy every moment of it.

The Road to Faster Flow Is Paved with Missteps: A Retrospective

Sun, 04 May 2025 21:30:00 +0200

This is a recording of my talk at the Fast Flow Conf NL conference, on the 27th of March, 2025.

Two years ago, we set out on a journey to transition to a Team Topologies-inspired organization, aiming to unlock faster flow and better collaboration. Today, it’s time to reflect on the lessons learned along the way.

Stop Copy-Pasting Your Resumé (and Everything Else)

Sat, 19 Apr 2025 00:00:00 +0200

You just got asked for an updated resumé. Again. So you open that folder—one in Google Drive, another buried in Downloads, and maybe another one in your email. There’s a version from three jobs ago, one you tweaked last year… and they’re all a mess.

But what if your resumé lived in source control? Versioned. Clean. Written in plain text. Ready to export to PDF in seconds.

That same approach works for more than just your own documents. When I’m hiring developers, I use AsciiDoc to generate technical assessments too—polished, structured PDFs without fiddling in Word. And once it’s generated, it’s automatically uploaded to the Confluence page for our hiring process, so recruiters and interviewers always get the latest version—without needing to ask.

In this post, I’ll show you how I use AsciiDoc to create reusable documents—like resumés, cover letters, and candidate assessments—that compile into beautiful, consistent PDFs in seconds. No CI/CD pipeline required - but you can absolutely add one later to automate PDF generation and publishing. Just structured content, a simple setup, and the joy of never formatting by hand again.

Testing GraphQL with Specifications: A Deep Dive with Reqnroll

Tue, 28 Jan 2025 00:00:00 +0000

GraphQL has been around since 2012, yet many developers haven’t had the chance to work with it. Personally, I’ve been using GraphQL on and off for several years, both in personal and professional projects. Recently, I’ve been diving deeper into it again—and I’ve fallen in love with it all over.

While implementing a few queries and mutations, I started to wonder: how could I effectively test my GraphQL implementation? Specifically, how could I send queries and mutations with a GraphQL client directly from my tests to ensure everything works as expected?

After some experimentation, I found a solution I’m excited to share: combining specifications with Reqnroll, the .NET WebApplicationFactory, and the Strawberry Shake GraphQL client to test a Hot Chocolate GraphQL server. This approach not only works seamlessly but also results in clean, readable specifications.

In this article, I’ll guide you through the process of setting up these tests, allowing you to test your own GraphQL server with clarity and confidence. Let’s get started!

DevOpsDays Eindhoven 2023

Mon, 16 Oct 2023 00:00:00 +0000

It was on my radar last year, but I decided not to go, but to go to Techorama instead. But, after hearing good stories about the first edition of the DevOpsDays Eindhoven, I decided to skip Techorama and go to the DevOpsDays Eindhoven 2023.

In this post, I will explain what the DevOpsDays are, and share some of my learnings. I hope you will enjoy it and, maybe, I might inspire you to join me next year!

Better Value Sooner Safer Happier, a review

Thu, 20 Apr 2023 00:00:00 +0000

Yesterday, I attended a session, presented by Jonathan Smart, on the topic of “Better Value Sooner Safer Happier” which was based on his book “Sooner Safer Happier”. The author’s approach is based on Lean, Agile, and DevOps principles, which have been adopted by many organizations worldwide, but with a strong focus on outcome, not on any process like Scrum, DevOps or Scaled Agile. In this review, I will share my key takeaways, I will not share his full talk, you can read the book and find some videos online.

My favorite books in 2022

Tue, 03 Jan 2023 12:00:00 +0100

My Goodreads 2022 reading list shows exactly 50 books this year. I did not break my record for the number of books (52, in 2017), but the amount of pages, 15.248, is definitely a record. Although reading is not about breaking records, spending time on a hobby is something that requires dedication and I am proud of my reading achievement. In this post, I will share my favorite, work-related books of 2022.

Advent of Code 2022: Learning Rust

Tue, 20 Dec 2022 09:00:00 +0000

Getting to the end of the year, you know it will be that time again: Advent of Code time! Starting on the first of December, up until Christmas, there will be a daily programming challenge. Last year I did an attempt to learn F#, which was not really successful. The combination of learning a new language and it being the first year I really participated in Advent of Code was just too much and after a few days I switched back to C#.

This year I wanted to skip it at all, but in November I decided to have a look at Rust and I got hooked. I looked for an IDE (more about that later), read a book and some documentation, did some of my favorite kata’s, and there it went wrong: I decided to solve some puzzles of Advent of Code 2021 and I decided to join this year’s edition again, with a goal: to learn Rust.

Chaos Engineering - Part 1: Simmy, chaos in code

Wed, 09 Nov 2022 21:00:00 +0000

Chaos Engineering is a hot topic and very cool to dive into. But knowing where and how to start can be a challenge. In this series, I want to demonstrate different sides and technologies you can use. In the first post: Simmy, a package to inject different kinds of chaos in a .NET project.

Using multiple Git accounts

Mon, 14 Feb 2022 09:00:00 +0000

Using multiple Git accounts and different Git platforms can be a challenge. In this post I explain how to configure multiple accounts, use different SSH keys and even verify your account.

Per Beining - XP Days Benelux 2025

Thu, 11 Dec 2025 00:01:14 +0100

Working together is more than just showing up!

Chris Hadfield

Tue, 27 May 2025 09:01:14 +0100

When you have some skills but don’t fully understand your environment, there is no way you can be a plus one. At best, you can be a zero. But a zero isn’t a bad thing to be. You’re competent enough not to create problems or make more work for everyone else.

Using an Azure Web App to host multiple static html sites

Tue, 05 Oct 2021 13:00:00 +0200

There are a lot of static site generators around and I have been using quite a bunch of them. While I used most of them for this (personal) blog, I have also used some for professional purposes like documenting software and for team and company-wide documentation. Especially Sphinx has proven itself to be quite useful.

I want to create an environment with the following requirements:

Hosting in an Azure Web App
Protected by Azure Active Directory
Every project has it’s own documentation (no merge conflicts between teams)
Use Sphinx but using other generators is possible

In this post I will show how to create a documentation platform which implements the requirements above with only a few lines of code.

Using xUnit fixtures with SpecFlow

Wed, 29 Sep 2021 11:25:11 +0200

It can be a challenge to implement new frameworks or tools in your daily life. Often it takes time to find out the quirks and best practices which can take time and even lead to doubts and abandoning frameworks. I have been using SpecFlow for a while now and I keep finding new ways to tackle issues and get cleaner code behind the specs (I am still having trouble creating clean & clear functional requirements though).

One of the things I keep bumbing into is using settings and sharing code between different specs. In the following example I will explain my latest find: using xUnit fixtures to get test settings and reusable api clients for multiple tests.

Managing a .NET Service with Blazor, on Windows and Linux

Wed, 11 Aug 2021 12:25:11 +0200

My employee has developed an application which “scrapes” data from systems, processes it and sends it to a central database. This is a WinForms application with a few screens for configurations and inspections. I was looking into different approaches for a new version and dived into the options of using a Windows Service.

I forgot where the exact idea came from but at a certain point I thought: what if I can install Blazor as a UI for a Windows Service. I could configure, start and stop, basically do all kind of things with this service if I have a Blazor Interface. I read something about systemd services with .NET too, so I could even create a cross-platform version (not that there is any need for Linux, but just because I can).

Well, after a few hours, I got it working so, in this post I will show you how to create a cross-platform service that can be installed on Windows (Service) and Linux (systemd) and be managed with Blazor.

Specflow and Eventual Consistency

Sun, 30 May 2021 20:25:11 +0200

SpecFlow is a tool which can be used to describe test scenarios and automate the tests. Although I have been using SpecFlow for a while now I never used it for advanced examples where time might be an issue. Lets show a simple example scenario first. A scenario, written in Gherkin, looks like this:

Scenario: Add simple item with due date
    Given the user enters "wash my car"
    And the user adds a due date of "1-1-2022"
    When the user saves the item
    Then the item "wash my car" is added to the list
    And the due date is "1-1-2022"

This scenario is easy to implement, the item will be added and stored. That’s it. Easy to verify, no delays, straight forward. But what if you have some microservices with a queueing mechanism? A scenario where data will be queued before processing so we can’t exactly know when the data is processed?

Arrowhead anti-pattern challenge

Thu, 07 Nov 2019 18:00:00 +0200

update (2019-11-08): added a bonus contribution from Bob, written in prolog

Just recently I had to work on a huge flow-chart to determine farm types based on the animal transports to and from farm locations. I started out with a small proof of concept but didn’t like the way it turned out. I did some research and learned I was basically creating a so called arrow head (“Arrowhead” anti-pattern ).

While it was nothing new, I never knew it was called arrowhead anti-pattern (or arrow anti-pattern).

Retry and fallback policies in C# with Polly

Thu, 18 Apr 2019 20:10:00 +0200

In this blog I will try to explain how one can create clean and effective policies to retry API calls and have fallbacks when requests are failing. With Polly it is possible to create complex and advanced scenarios for error handling with just a few lines of code.

This week I was connecting an eCommerce web application to an ERP system with REST APIs. There are multiple endpoints, all authenticated with OAuth. To make sure all calls to the APIs will have a high success rate I had to implement retry mechanisms for different scenarios.

Things I Learned This Week - #1

Thu, 04 Apr 2019 20:56:07 +0200

My plan was to write a quick post about some cool things I found and learned this week but I just learned too much (as I do every week). Below are just the highlights, I will try and write more posts like this, especially if I get some cool comments :)

Read about a REST Client, Unit Testing, TFS and more in this post!

Asynchronous Model Validation

Thu, 07 Mar 2019 19:52:10 +0100

UPDATE: Kamil Grzybek commented on my article and pointed me in this direction: a blog post about Async OOP 2: Constructors by Stephen Cleary. While I still my post, I realize it is a bad practice.

Last week I found some great articles about Domain Driven Design. While I have been trying out various patterns and design principles like Clean Architecture and Domain Driven Design I was still finding out how to implement domain events. While doing some exercises I came up with a solution to validate domain entities with asynchronous validations which I want to share.

Using Google Sheet as CMS for your App - Part 1

Tue, 25 Sep 2018 17:00:21 +0200

Imagine you had an easy to understand CMS without too much overhead, just to add translations and a bit of content for your (Xamarin) app. A CMS with an “excel-like” interface, an interface most of your customers would understand without even a training? Say “Hi” to Google Sheets & Azure Functions!

Using an Arduino with Xamarin for Mac

Mon, 03 Sep 2018 11:28:14 +0200

It’s all about first times: my first Xamarin.Mac app and my first Arduino connection with a Mac. I am going to explain how I connected an Arduino to a Xamarin.Mac app to create a “pomodoro-like” timer.

Google Places Api

Sun, 26 Aug 2018 22:00:04 +0200

The Google Places API can be used to find locations and their details like geolocation, address and other data. It returns a predicted list of locations based on the input string. In this post I will show some details about the plugin I created.

Using MediatR in an MvvmCross App

Tue, 07 Aug 2018 20:30:01 +0200

Intro

A while ago I was listening to a podcast from DotNetRocks about Clean Architecture. Around the same time I read something about a Clean Architecture template which happens to be from Steve Smith, the same guy talking about it on the DotNetRocks show.

2024-08-29

Mon, 01 Jan 0001 00:00:00 +0000

Meeting

MEETING Workshop 2 [2024-08-29 Thu 09:00]

With:

Mitchell (RS), 7 years RS. Bijenkorf. Liander (Arnhem)

Question from yesterday:

API of co-pilot possibilities

Recap van yesterday

Struggle to find the scope
Got started, but without an introduction of the theme
But, at least we had some outcome

Today

Intro
Trying to focus on getting some more, practical outcole (if that is correct?)

General

Azure stack (power BI, data lake)