Posts
182 posts, newest first. Every post is also available as JSON and markdown at {slug}/post.json and {slug}/post.md. The whole corpus in one request: corpus.json (markdown).
- Rapid Iteration in Agentic Loops · Taking output as input
While working with AI-agents to build things I often iterate through versions of the thing I am building. You try, experiment, fail, improve, and again. In the manual days before AI, I checked results by hand. But what if we teach agents to - It Observes · An intelligence watching Earth
An observer writing a daily log of what it sees watching Earth, it uses no names of countries or organisations, instead it speaks in metaphorical descriptions. Its distance provides an alternative perspective on our daily news. Let me tell - Agentic Coding on a Linux VPS · Set up a dedicated 'werkplaats' for Claude Code
Large language models are commonly accessed in chat form, you ask or prompt something and the 'AI' answers. That's cool, but when you give the model access to digital tools, it can actually do things like looking things up, compiling code a - Trail Running · Through mud and nature
Doubling my daddy duties with my love for endurance sports, I decided to take advantage of me living in the countryside and run to the store through nature, following local creeks and trails. It's a unique experience, I may even like it bet - Change Keeps Coming · The Pathless Path by Paul Millerd
Suggested by a friend in thinking, I just finished reading the book 'The Pathless Path' by Paul Millerd. It sits right next to Brad Stulberg's 'Master of Change' on my mental shelf for the same reason: both quietly push back against the urg - Offline Reading · Exporting blog posts from HTML to ePub and PDF
This year marks the 10th anniversary of my blog. What started as an experiment has evolved into over 170 stories, averaging around 60 thousand pageviews a month. I recently started translating posts into Dutch, German, and Spanish, expandin - Using a mechanical keyboard · NuPhy Air60 V2 review
Since two months I have been using a mechanical keyboard, a NuPhy Air60 with Moss (60gf) switches. I long doubted the value of replacing my standard keyboard, liking keyboards from Apple and Framework enough not to switch. After reading lot - Hello Video · Greeting you with a smile!
Just look around the modern web today, thanks to AI generated texts and images everything feels polished, perfect... and a little cold. I wanted to break the proverbial ice with a simple smile. So I replaced my hero photo with something ali - Websites with Auto Pilot · Up to date content with scheduling, feeds and AI
Why do you need a website, and what can you do to maximise its value while minimising (manual) effort? I have been working on this with some of my most innovative customers. What if you no longer need a full blown manual content management - The Future of AI is Human · On Fairies and Gin-Tonic with Blueberries
AI got me thinking lately, why would one still want to work? Perhaps today's imperfect AI is not ready yet, but imagine everybody has access to a near perfect intelligence, capable of solving hard problems and answering even your wildest qu - Omarchy on iMac · Breathing new life into an old computer with Linux
After helping a family member migrate to a new computer, I found myself with an old iMac. The machine from 2017 was very slow running modern macOS, yet I have a soft spot for these all-in-one computers designed by Jony Ive and his team. Cou - Auscultare Podcast + Audiobook Player · Building a native Android app that remembers where you've left
Enjoy distraction free listening to long form audio files like podcasts and audiobooks using this app I made. Tired of bloated apps full of ads, subscriptions or 'suggestions', I wanted an app that gets out of my way by doing one thing only - Android Photo Library App · All your photos in your pocket with Aves Gallery
In Europe the summer holidays are nearing their end and if you are like many young parents, you probably shot a ton of new photos and videos. These are not just a bunch of files, they are like windows into our personal memories. This post i - Willemstagram · 3D flip-flap photo display showing stories
Last week I sat with a customer looking at the new willem.com homepage where I use a narrative to tell about the things I do. This customer is one of the best visionary create thinkers, yet my text didn't seem to speak to him. Thinking abou - Towards Digital Sovereignty · Turning my experience into your advantage
Over the years I have experimented with different digital tools, platforms and apps to get my work done. From easy-to-use but locked down commercial systems to free/libre solutions that are powerful but more challenging to setup. I learned - The Agentic Web · "Voorsorteren" for the future
In Dutch, there's a great word: voorsorteren. It means getting into the right lane on the motorway long before your exit. You do it to ensure a smooth, stress-free journey. I believe the same principle applies to technology. A little bit of - The Power of One · Why I've chosen to build my business by staying small
For my entire career, I've had a clear goal: to stay a company of one. This isn't a starting point, but a deliberate choice about the best way to do great work and build a sustainable business. In this post, let me explain why. - Breaking Changes · Upgrading Dovecot 2.3 to 2.4 in Debian Stable
Last week I ran into unexpected trouble during a routine maintenance procedure on my company's email infrastructure. Processing thousands of emails each day, we use Dovecot to give our clients access to their messages. That all came to a gr - When the Going Gets Tough · Running the Leiden Marathon in Heat
Yesterday I finished the Leiden Marathon, it was the hardest 42K I ever completed due to the temperature. Sunny with a clear sky, temperatures climbed to 25°C. Several runners collapsed from heat exhaustion, and one even required resuscitat - Vibe Coding · On the power and danger of programming with AI
Grossing over $48K a month, the flight simulator game by Pieter Levels spurred a whole flurry of innovation. Without detailed knowledge of 3D game engine technology, he 'vibe coded' his game using AI. Critics of his work pointed at security - Workout data in 3D · Exploring web-based 3D graphics for fitness data
While running my rounds around the village, it struck me that I could use ThreeJS to craft a dynamic 3D representation of my workout data. Read along to see what I’ve created—it’s a work in progress but serves as an exciting exploration of - Open-Sourcing Gran Fondo · A Leap to Libre Fitness and Freedom
Gran Fondo, the app that tracks runs and rides, is going open-source. I’m removing its subscription model and make it libre. This isn’t about short-term revenue—it’s about building something enduring, private, and free for all. Here’s why I - Durable Smartphone · Fairphone with Google Free /e/OS
While sitting in the train the guy in front of me surprised me, out of his fancy pants he pulled this well worn, patina rich, piece of tech. We're travelling first class and judging by his classy attire, this man is not of limited means. Li - Better Laptop · Assembling the DIY Framework 13
Consumer electronics often lock us into sealed hardware and forced upgrades, creating enormous e-waste. Framework challenges that norm by making laptops you can service, upgrade, and customise, which extends their lifespan and cuts down on - Podcast Downloader · A Simple, Open-Source RSS Podcast Fetcher
Tired of being constantly nudged toward "more relevant content", I built a script to break free from commercial or closed-source podcast apps. I just wanted a tool that quietly grabs my favorite shows—no fuss, no tracking, no extras. Read t - Champions League of Webdesign · Cutting-edge technology meets top-tier digital demands
Creating a high-performance website is an art form that blends cutting-edge technology with an eye for design and commerce. At escape.nl, home to one of Amsterdam’s most iconic venues, every detail reflects the precision and care required t - Master of Change · Thriving amidst uncertainty using Rugged Flexibility
Change is one of life's few constants. Yet, even with its inevitability, facing it head-on can feel daunting and disorienting. In the book "Master of Change", Brad Stulberg offers a thought-provoking guide to not just survive but thrive in - Data versus Feeling · Running two marathons in 6 weeks
Earlier this month I ran the Valencia Marathon (42KM), just six weeks after finishing my first ever marathon in Amsterdam. I used two different approaches for these races: running on feeling and running on data. The experience differed grea - The Problem With Bitcoin · Everybody Wins
A few days ago the value of a single Bitcoin briefly surpassed $100K, a milestone that seemed unimaginable just some years ago. I wonder how durable the ever growing love for Bitcoin is. Let's have a closer look at the mechanisms underpinni - Write your own words · Against AI for writing
Two years ago ChatGPT launched, it popularised AI as tool to create things. Large language models generate text based on prompts, outputting words that are hard to distinguish from being written by a person. The short term benefits are clea - Go Viral on X · 32K views in two days
Earlier this week one of my posts on the social network X went viral and attracted 32K views in two days. With no major presence on Elon Musk's platform, and no paid advertising, gaining that kind of attention is something special. Let me e - Marathon · Running my first full marathon
Last Sunday I completed my first full marathon, covering a distance of 42KM in and around Amsterdam. An idea that started in a bar with some beers and concluded with a finish in the Olympic Stadium. What a journey, what an experience, well - I see dead people · Augmenting old photos in virtual reality
Imagine seeing your dead family members - not just on a picture, but lifelike and in three dimensions! You can almost touch them. It hits you differently, I can assure you. I'm still in awe: I just saw my dead grandfather, lifelike and for - Developing a native iOS app · Making a cycling and running tracker
As a little side-project, squeezed between my normal work, I have been working on something of personal interest: a native workout tracking app for iOS. I wanted to make my smartwatch obsolete, instead using my phone to track workouts. How - Half Marathon · On Training, Data and Feeling
Last Sunday, I participated in the Venloop, a half marathon event in Venlo. I completed the 21KM run in 2h05, a result I am satisfied with as this was my first ever 'official' event since I began running just three months ago. In this post, - No, I Won't Build That! · Better Thinking, Better Work
If you're an accomplished developer (as in: you've actually created things in the past), you may recognise this scenario: people reaching out to you, asking you to build something specific. "Can you build X for me?" A fellow technician once - Vision Pro · Exploring Spatial Computing
Currently, I am overlooking a lake at Mount Hood while writing this. I hear birds in the distance and see the lake calm, with subtle waves and some mist in the distance. Yet, it is fake, as I am sitting on our top floor, a barely furnished - Health and fitness data · Is more better?
Since the start of this new year I am working out harder than the previous months. I have set some goals for myself and have taken on a training scheme incorporating running, cycling and swimming. As I sift through the growing mountain of w - Backup Rotation Scheme · Rotate your backups with 'rsync-backup-rotator'
In today's digital age, safeguarding your data is paramount. Simply creating a copy of your files may not be enough as they can get corrupted, overwritten or blocked by ransomware. Having multiple, time-rotated (and ideally, offsite) backup - Apple Watch as Phone · Replace your smartphone with a smartwatch
Imagine a week without your smartphone, replaced solely by the sleek simplicity of a smartwatch. This week I did this, leaving my smartphone behind and letting an Apple Watch take the helm. Many hail this as a liberating escape from our att - And... there is light! · Installing dynamo powered lights on my road bike
The darker days are here in the northern hemisphere, and so is the need for good lights on your bike. Although battery powered lights can do the job, you need to keep them charged. I wanted a light system on my road bike that just works. Re - Giving AI Training · Teaching folks about the superpowers of GPT
Yesterday, I had the pleasure of leading a training session on the application of cutting-edge AI techniques, such as OpenAI's large language models (GPT), for a team of individuals from varied backgrounds, education levels, and disciplines - Hello, stranger · Talking to random people
While enjoying my fresh wok lunch in Amsterdam, I noticed something odd: other folks coming in for something to eat ignored the person standing at the counter, preferring to order through a digital kiosk. The crazy thing about this? They ar - The Same, Differently · Where You Are Matters
It's been over half a year since I moved from the city to the countryside. I regularly travel between these locations for work and leisure. Being a cycling enthusiast, I keep a bike at both places, and this has led me to discover a funny th - Impact of training · Analysing WHOOP's trend data
This Monday I completed 235KM on my fixed gear bike during the Fietselfstedentocht 2023. It was a nice ride with fair weather and favourable wind conditions. Yet, I took the challenge seriously and prepared myself with some proper training. - Tablet as Tool · Appreciating iPad Pro: A Different Perspective
The iPad Pro's utility has sparked much debate recently. Some users argue it's a disappointment, failing to meet expectations set by traditional laptops. However, there are less obvious benefits to the iPad worth considering. This blog post - Using AI to generate code · Programming with super powers
As part of my software optimisation efforts to cut cloud costs, I needed to replace an existing piece of inefficient server software with something that uses more robust (yet fragmented) tooling available in Debian GNU/Linux. Could the GPT4 - Working Offline First · Learning from a 15-year old ThinkPad X200
As part of a greater plan to optimise my entire workflow, I am doing a little experiment this month: using a 15-year old ThinkPad X200 laptop as main computer. It’s from an era before “the cloud”, popular among free/libre software enthusias - Tips for Long-Distance Cycling · Riding 204KM on a fixed gear bike
In preparation for this year’s Fietselfstedentocht (236KM), I took my bike and set out for an adventurous ride through half of the Netherlands. It was my first long distance ride after being infected with COVID. If you're considering a long - Cutting Cloud Costs · The Significance of Software Optimisation
Like many, I faced soaring cloud service costs for my clients, prompting a wake-up call. To stay afloat, it's essential to incorporate software optimisation as a strategy for managing cloud expenses. Join me as I share how I managed to save - Back to the University · Diving into Scientific Programming
This month, I headed back to university for a special course on scientific programming. With numerous recent advancements in machine learning (referred to as "AI" in PowerPoint parlance), including ChatGPT, it felt like the ideal moment to - Rolex DateJust 36 · A crown for every achievement
The year 2022 has been very special to me, after working very hard to make it possible: me and my family finally made the big move to Limburg. To commemorate this milestone, I got myself a timeless timepiece: the Rolex DateJust 36. Read on - Moving to the countryside · Leaving the big city for a small village
This month marked "the big move": relocating my family from Amsterdam to Noord-Limburg's countryside. Motivated by my wife's longing for her roots and our desire for space, the timing felt right. As our oldest child neared four years and pr - MUSE in Carré · Rock meets elegance
Last Sunday I experienced a breathtaking fusion of legendary rock band MUSE and Amsterdam's iconic Royal Theatre Carré. The band's electrifying sound in the theatre's sophisticated atmosphere proved to be a recipe for an unforgettable night - The Ultimate Freedom Bike · Riding the Brompton foldable bike
Rarely have I been so amazed by a bike: the past 5 months since I've picked up my Brompton foldable bike in Amsterdam have been great fun! About 500KM down the road, I'm happy to share some of my experiences with this ingenious piece of eng - Computer says no · How today is ruled by Artificial Intelligence
This morning I enjoyed my bike ride on a nearly empty bicycle lane, picture perfect rays of sunlight illuminated the dew above the fields around me. Where were all the other cyclists? I suspect it has something to do with popular weather ap - CAPTCHA Alternative · Protect your forms in a user friendly way
Chances are that you've encountered a CAPTCHA in the wild: they protect web forms by asking you to type over weirdly rendered characters or by asking you to select photos containing a particular thing. Why are they used and is there a user - Offline Music · Streaming Music Alternative
Music has the universal power to move people. Different rhythms, emotions and vocals enable us to enjoy music very personally. Music is very close to my heart and I don't like anything to get in between. Therefore I don't rely on streaming - Snake '97 High Scores · Game inspired art by Zena Van den Block
Last week I received a very kind invitation from a Belgian artist, to attend her art exhibition in Antwerp. The work on display involved the Snake '97 game that I have created. Uttering to find the right words and thrilled with excitement, - Wearing WHOOP 4.0 · Why you should wear a biometric sensor
How often do you look in the mirror? Probably more than a few times a week! I have been thinking about this ever since I received my newest WHOOP 4.0 biometric sensor. It's great. But, why do I wear it? What value does it provide? Why shoul - For the love of mini · The unexpected greatness of iPhone Mini
People regulary ask me why I have a small smartphone, a modern iPhone 13 Mini. Often I simply reply that I like it. The smaller size offers more than just an easier fit in your pocket. I have come to appreciate its intangible greatness, rea - Escaping the flat tires · Are puncture-proof tires really puncture proof?
You might wonder how puncture proof a "puncture-proof" bicycle tire really is. I set out to find the answer when I installed Schwalbe Durano Plus tires on my bike. It was inevitable for me to find the answer to the question: How many kilome - Using Google Free Android · Volla Phone as alternative to mainstream Android and iOS
Nearly all folks I know use iOS or Android from a mainstream smartphone brand, yet alternatives still exist! The German Volla Phone prides itself to be a worthy option for those who value privacy and freedom. I bought one to experience it f - Inspiration from a child · Experience the world like a kid
Together with my kids I love to explore the world that we think we know as adults. A kid's perspective inspires and surprises! No need to travel half the world for an adventure: Fly planes, catch bad guys, solve problems, build and break st - Protecting VMware ESXi · Improve security using a firewall and proxy server
In response to an incident on a server, I detected a possible security breach. The affected machine ran VMware ESXi, a bare metal hypervisor used to run virtual private servers. In standalone mode, a web based management console offers full - The birth of a child · Impact on daddy and his biometrics
Today I witnessed the birth of my daughter! You feel humble as a man, witnessing the labour and magic. Not sure if I can come up with something having more impact on a man than this. For the purposes of science and curiosity I wore a biomet - Migrating to the Cloud · Clearing an on-premise server room
For a Dutch organisation that serves customers throughout Europe, I was asked to help dismantle a live server room. Instead of simply pulling the plugs, some of the services had to be migrated to the cloud. For fun and inspiration I share t - Wearing Grand Seiko · On craftsmanship, innovation and practicality
Sadness could be seen in my eyes when my custom made watch got damaged earlier this month, while awaiting repairs I was fortunate to wear a Grand Seiko. Its unique mix of craftsmanship, innovation and practicality is worth sharing with you. - Using the reMarkable paper tablet · Read, write, think and repeat
This month I received my reMarkable paper tablet and ever since I have been using it extensively: reading, writing and thinking. The paper-like display makes you forget about its digital innards. Read along for my thoughts. - Hospitalised with MCADD · Averting a metabolic crisis by infusion
This week we experienced the first time that our son was hospitalised since he was diagnosed with MCADD, a metabolic condition that limits his body's ability to utilise fats for energy. Do you or your kid have MCADD? Then, read along and do - Enter text without keys · Tap: the wearable keyboard and mouse
This month a special piece of wearable tech arrived for me to try: the Tap Strap. Worn on your fingers, the Tap Strap recognises tapping and moving. It enables you to control and type your computer without a mouse or keyboard! - Fixed Gear Gran Fondo · Cycling 176KM through rain and wind
Today I took my fixed gear bike for a ride, 176KM from Amsterdam to America (Limburg, The Netherlands). Rain and wind added to the challenge, creating an ultimate test for man and machine. Let some of my fun be of inspiration to you! - Art of visualisation · Creating mouth-watering food photos
You learn from working with experts and this month I had the privilege to work with a professional food photographer, my brother. Together we set out to photograph the entire menu of Café Carbòn in Amsterdam, enjoying the fabulous food afte - Three tips to make a content strategy work · Maximise the effect of your writing
When you write for your blog or for your company's website, there are things you can consider to maximise the discoverability, longevity and impact of your writing. Leverage the energy you put in into your words. Today I share with you thre - Wearing two watches · Both a mechanical and a smartwatch
For the past weeks I have been wearing two watches, and boy this is a thing! I love my mechanical watch, but I needed the modern connectivity of a smartwatch. I couldn't choose between them, so I decided to wear both. It's not as bad as you - The value of notifications · How to setup your smartphone to save time
It's easy to dismiss your phone's notifications as something that disturbs you, something annoying. But if you take the time to set them up correctly, notifications can actually save you time in the long run. Gain more focus by taking contr - Realtime service uptime monitoring · Discover problems before your customers do
Downtime happens and it is nothing to be ashamed of, just make sure that you set yourself up to discover problems as soon as possible! You can use realtime uptime monitoring to automatically keep an eye on your servers and services. Read al - Building a product platform · Designing for reusability, flexibility and extensibility
This month I am leveraging platform capabilities to launch a new product. Over the years I have developed the "Lemmid" platform, a set of building blocks that allow me to swiftly develop new products. Designing a platform takes some extra c - Abandoning my own tablet OS · Why I moved back to iPad and the Mac
The past year I have been experimenting with creating my own tablet operating system using Debian GNU/Linux and the i3 window manager on a Microsoft Surface Go 2 with LTE. After months of intense use I have now decided to abandon the experi - Commuter bike checkup · How is my commuter bike doing after 21.000KM?
This week my trustworthy commuter bike started making strange squeaking noises when braking. It has been just over three years since I started cycling on it. People frequently ask me how the bike is performing and how the Gates Carbon CDX b - Working with special hardware from China · On developing software without a manual
This month I received a shipment from China containing some special hardware, Android devices with embedded printers! To make life easier for the restaurant and business owners that use my food ordering app, I want these devices to automati - Why Apple Silicon is a big deal · Blown away by a MacBook Air
Apple now designs its own processors and I had a chance to work with the very latest from Cupertino: a brand new MacBook Air with M1 processor. Never ever have I been so blown away by a MacBook Air, pun intended. Let me share some thoughts - Designing a multi dimensional capacity queue · Managing kitchen-, delivery- and pickup capacity
This month I needed to create additional dimensions to a capacity queue mechanism. The food ordering app that I created needed to be able to restrict capacity based on the number of orders, the contents in individual orders and the dispatch - Designing my own watch · Timeless timepiece, both functional and comfortable
Last month a very special package arrived from Switzerland, containing my custom made wrist watch. I decided to sell all my big brand watches and have them replaced by something unique, tailored to my personal preferences. This is the story - Replacing a Shimano shift cable · Fixing the cargo bike after hunting for bears
Last week my son and I where looking for bears in the local park... a child's fantasy is priceless! Unfortunately, during some off road riding with our cargo bike, one of the cables got tangled up with a sturdy branch! Our wounded carbo bik - The joy of a simple laptop · Surface Laptop Go with Windows 10
Every now and then I switch my gear to keep a tap on what is going on outside my regular tech habits. You’ll be amazed by what you can learn from trying out different things. This week I had a chance to test the Surface Laptop Go running Wi - Increase traffic to your blog with a RSS feed · How to setup RSS/Atom using NodeJS
Writing for my blog has been a lot of fun, I receive messages from all of the world about the things I like. Traffic is growing, every month more readers are finding their way to my blog. This week I received a request to support RSS feeds - How to use rsync to make backups · Explaining a powerful file transfer tool
It is very important to make backups of your data, as you never know when disaster strikes! One powerful, cross platform, tool to help you achieve this is 'rsync'. In this post I'll explain why rsync is useful and how you can use it to set - Rescuing photos from a crashed iMac · Using advanced tools to read files from a faulty disk
This week I received a message from someone with a iMac that crashed. It contained more than 50.000 photos, covering two decades of personal history. As there was no backup, it was up to me to attempt to safe as much as I could. Could I pos - Riding with Omata One · Analogue cycling computer with GPS
For the past week I have been riding my bicycle with Omata One, a special bike computer. Its mechanical hands indicate speed, distance, ascent and time ridden measured using precise GPS data. It is fun, read along to know why. - Refining my tablet OS experience · Using Surface Go 2 with 4G/LTE, Debian GNU/Linux and i3wm
Earlier this year I tried to create my own tablet operating system by installing Debian GNU/Linux on a Microsoft Surface Go tablet. I learned a great deal about what I like about tablets. But I still preferred my iPad Pro, mainly because of - Syncing files seamlessly between smartphone and tablet · Using unison to automatically sync between GNU/Linux and the iPhone
In order to optimise my workflow, I was looking for a way to seamlessly access the same files on both my computer and smartphone. This is useful to when you want to quickly send files from your computer using your smartphone through various - Free from the iCloud: Escaping Apple Photos · Using offline photo library management software
After encountering the umpteenth ‘magic’ bug while managing my iPhone’s photos, I was done with it. Apple came a long way since it launched iPhoto (the predecessor of iCloud Photos). But for something as valuable as my personal memories, I - Cleaning a vintage watch · Rediscovering old beauty under layers of dirt
This week I was cleaning my closet when I found an old watch. It came from my grandfather’s house. It looked like it had an adventurous live, full of wear and tear. I recognised that it had an automatic mechanical movement. Upon picking it - The best keyboard for iPad · Smart Keyboard Folio vs Magic Keyboard
The tablet is at the frontier of mobile computing and its hardware form factor is evolving. This year Apple introduced a new Magic Keyboard for iPad that includes a trackpad. Everybody is raving about it, yet I think there is something to b - Influencing purchase behaviour · Applying behavioural sciences principles to the purchase decision process
This week I stumbled upon a brilliant report on how people make their purchase decision. For my work on the online food order app I am continuously looking into scientific sources to improve performance, conversion and online revenue. This - Upgrading a 27-inch iMac 5K to 14 terabytes · Replacing the Fusion Drive with both a SSD and an harddisk
This month I did an attempt to upgrade my 27-inch iMac 5K. I wanted to replace the fusion drive with a SSD and a large hardisk. In addition I decided this was a good time to upgrade the RAM memory as well, maxing it out at 64GB. I was on a - Repairing a Giro AEON bicycle helmet · How to replace the Roc Loc 5 system
This month my trustworthy Giro Aeon bicycle helmet broke down! Normally I wouldn't hesitate to invest in safety and thus buying a new one. But I like the Aeon helmet so much that I went through some extra trouble to fix it. Read along to se - Some thoughts on touch screen user interface design · Creating intuitive natural interfaces
Past weeks I have been working on a new app involving personal health. The main challenge is to come up with an intuitive, natural interface that works well on small touch screen devices. But what is it that makes an touch screen interface - Tudor Black Bay 36 long-term review · Six months on the wrist
For the past six months I have been wearing the same watch, pretty much every day and night. It's a Tudor Black Bay 36 watch in steel, with a black dial. I like minimal (yet functional) design that lasts, this watch certainly ticks the righ - Linking Lemmid Store with kitchens · Integrating with external systems that you don't control
As part of the food ordering app I am building, I needed to design a reliable way to link the app to external systems. These external systems are beyond my direct control and include different checkout registers, kitchen management systems - Different ways to visualise health · Looking at games and fitness apps
This month I did some research into how health is visualised in fitness apps and games. For a new app involving personal health I am looking for an intuitive way to visualise how healthy one person is. There are many colourful approaches ou - Scalable application design without magic · Leveraging client computing power for high performance with many users
As part of the online food ordering app I'm building, I needed to design a scalable backend infrastructure that could handle lots of concurrent users. Scalability is considered a hard problem to tackle. Often it's presented like it's someth - Designing an interface for a food ordering page · Striking a balance between powerful options and mobile usability
Online ordering pages are more important than ever before. The COVID-19 virus, the resulting lockdowns and the social distancing rules have emphasised the need for a well-designed webshop user interface. This is surprisingly hard to get ri - Minimalistic road bike with Gates carbon drive · Meet your new therapist: the Schindelhauer Siegfried Road
For the past few months I have been riding a special kind of bike, the minimalistic Siegfried Road from Schindelhauer. It is unlike most road bikes as it lacks a conventional chain and derailleur. It features the Gates CDX carbon drive. It' - Talking tablets: what makes a great tablet? · Working with Microsoft Surface Pro X
Earlier this year Microsoft released their brand new Surface Pro X tablet computer, in many ways this is a forward thinking device. As I like working with tablets I wondered what exactly makes a great tablet? Is Surface Pro X any good? Read - Traffic shaping using iptables and tc · Limiting outbound network bandwidth per client IP-address
Last month I received an automated alert indicating excessive bandwidth usage, usually a sign of trouble. When this happens, you should follow a standard incident procedure, trying to isolate the source of the traffic before shutting it dow - Designing and implementing a (micro) payment system · Monetising my blog with coffee, Apple Pay and Mollie
Online payments are now more important than ever as businesses are disrupted by the COVID-19 virus. It drives my customers to seek new ways to make money online. I designed and implemented a (micro)payment system. This post is about achievi - Making my own tablet OS · Installing and modifying Debian GNU/Linux on Surface Go
For some years now I use a tablet as main computer, I like its versatility. But, most tablets come with a locked down operating system, like iPadOS, Windows 10S or Android. As I like things my own (weird) way, I wondered if I could escape t - Monolithic vs Microservices software architecture · Choosing the right design for your app development
This week I flew to Gothenburg to meet people from a large international shipping company, talking about the development of enterprise level software. During the meeting there were various experts in the room, one of them asked me on choosi - Your own addressbook and calendar cloud · Share contacts, agendas and tasks with CardDAV/CalDAV
If you use different devices and computers to get things done, you might want to synchronise contacts, agendas and tasks. You can use any of the 'big cloud' services for this, like Apple iCloud, Microsoft Office 365 and Google Gmail. But, i - The day I sold my car · Looking back at my years with Smart Roadster
This week I sold my car, I now no longer own one. For me, this is something of a change as over the years I owned various sports cars that were like a hobby to me. My discovery of cycling and the birth of my son changed this. But if you're - Measuring cholesterol levels in blood · Know your LDL, HDL and Triglyceride numbers
This week I went to my doctor to have my blood examined, to determine my cholesterol levels. Over the past years I have been paying more and more attention to my health. After improving my lifestyle considerably, I wondered what my numbers - Improve your sleep by blocking light · On the benefits of wearing a sleep mask in bed
Over the past few weeks I have been experimenting with wearing a sleep mask in bed, blocking all light. Our bodies produce the sleep hormone, melatonin, in darkness. Living in an environment awash in artificial light, is therefore exactly t - Whoop strap review: 24/7 wearable sensor · Beyond fitness tracking and smartwatches
The past months I have been wearing the WHOOP Strap 3.0, a wearable sensor that collects health and fitness data. It's different compared to most other fitness bands as it was designed with professional athletes in mind. It is focussed on d - Realtime human pose recognition through computer vision · Using TensorFlow and PoseNet on a video feed
For an exciting new project I have been experimenting with computer vision using TensorFlow. I wanted to achieve realtime human pose detection to drive interactive video projections and games. Time to dive into the world of machine learning - Supernova E3 Pro 2 dynamo powered headlight · Replacing my bike's headlight
Earlier this month my dynamo powered headlight on my commuter bike needed replacing. One of the electrical connectors broke of, likely caused by intense daily use. I searched for the best possible light, one that would be extremely durable - Building a professional 72TB NAS · Configuration and installation of an HPE ProLiant DL380 server
Over the past few years I have been moving my data and work from local computers (mostly laptops) into the cloud. Cloud computing is done by servers in a datacenter, powerful computers that do the hard work. As my company grew, I needed mor - Flying in a C47-A (DC-3) classic plane · Aboard the 75-year old royal PH-PBA dakota
As a wonderful birthday gift I was honoured to fly in a DC-3 classic plane. It was the 75-year old PH-PBA, a C-47A Skytrain or Dakota, formerly owned by H.R.H. Prince Bernhard from The Netherlands. It's a very special plane operated by the - Multi-Window support in your iPad app · Native development for iPadOS
Last month Apple released iPadOS, the first dedicated operating system for iPad. It differs from iOS with its support for the larger iPad screen, including multi / split screen windows. I develop apps and it was time to take advantage of th - Visiting an international hackers conference · OWASP Global AppSec Amsterdam
This month I was lucky enough to attend Global AppSec Amsterdam, an international conference for hackers and security specialists. There were presentations from former intelligence agents, bounty hunters, academics and software vendors. I l - Fighting backscatter spam at server level · Configure Postfix to block spam before it enters the server
This month I had to deal with backscatter spam, affecting one of the mail servers I manage. As server engineer I make sure that servers don't send spam and that incoming email gets filtered. Despite all good efforts, this server kept being - Riding with a power meter on your bike · Installing and using the 4iiii Precision Powermeter
After I created a minimal road bike, I decided to install a power meter to find out what's it like to measure the power output of my legs. What can you learn from a power meter? Is it difficult to install? Is it worth it? Read along to find - Creating a minimal road bike · Recombining and refinishing old parts into a new bike
Over the past months I have worked on different bikes, leading to an accumulation of spare parts in my garage. I wondered how hard it would be to make a new bike using these spare parts. I decided to take advantage of this moment to refinis - Limitations of sleep tracking using a wearable · Comparison with a chest strap HR-monitor
Sleep monitoring is a popular feature of many smartwatches and wearables. Devices like Fitbit, Withings, Apple Watch and Biostrap analyse biometrics during your sleep. These wearables are worn on the wrist and use optical sensors to capture - Optical vs chest strap heart rate monitors · Measuring beats per minute using different sensors
With modern wearables, smartwatches and fitness bands, it has become easy and common to measure your heart rate. There are however fundamental differences in sensor types. Some sensors capture the electrical signal from your heart while oth - Assembling a cargo bike · Setting up the Babboe Big cargo bike
This month our Babboe Big cargo bike arrived, in boxes. The engineer in me thought it was a good idea to assemble the bike by hand. This way I would know exactly about all its parts and fittings, handy knowledge for maintenance. Read along - Six months with MCADD · Thoughts and tips on the daily life as parents
Tomorrow it's six months since our son was born, a good moment to reflect upon the experience of being a parent of a kid with MCADD. This metabolic condition demands special attention on the feeding schedule and preparation for situations w - Solo around the Markermeer (211KM) · Tips to prepare, to endure and to enjoy long distance cycling
This week I took my bike for a long distance (211KM) ride around the Dutch Markermeer, solo! Unlike participating in an organised event with service, support and company along the way, going solo requires a different preparation, mindset an - Dig for dummies · Explaining an highly useful network tool
When you're building websites, apps or email services you may run into domain names and their configurations. When everything is working as it should, most of this is invisible. But when troubleshooting a domain name configuration, it may b - The best bike computer app: Cyclemeter · Get advanced ride data with a flexible setup
This month I have intensified my training to become fit for this year's Fietselfstedentocht, a 235KM bicycle ride through Friesland. Over the years I have tested different kinds of bike computer setups: from dedicated (and expensive) Garmin - Search like a pro: Google search operators · Comprehensive list of advanced search operators
You probably use the world's most famous search engine to find things everyday, but you might not know about some of its advanced search operators. You can use these special search phrases to find things that are otherwise burried in the se - WordPress: 10 tips to secure your website · Keep hackers out of the world's most popular content management system
A lot of people use WordPress to manage their website, therefore it's no surprise people ask me to have a look at their site's security. As ethical hacker, I encounter WordPress in different shapes, sizes and states. Some of them are really - Servicing a robot vacuum cleaner · My iRobot Roomba is now running for 8 years and counting!
Back in 2011 I got myself an iRobot Roomba 555 robot vacuum cleaner to automatically clean my apartment. It's a little circle shaped robot that drives around sucking up dust bunnies. Over the years it has bravely fought the dangers of my ap - Understanding the security concerns in shared hosting · Considering open ports and unused network facing services
People pay me to hack them, provided I'll explain how it was done, so future hacks can be prevented. As security consultant, I scan for weaknesses in my clients' apps, webshops and websites. Very often a hack starts by exploiting a security - One year on the ultimate commuter bike · 6000KM in 12 months with Gates CDN/CDX and Shimano Alfine
A year ago I tried to create the ultimate commuter bike, a modified Sensa Cintura with the Gates CDN/CDX carbon belt drive. I received lots of messages from cyclists and commuters from all over the world. From the Swiss alps, France, Italy, - Born with MCADD · Medium chain acyl-CoA dehydrogenase deficiency
Just days after our son was born, we ran into trouble when our little man didn't want to eat anymore. Repeated attempts to feed him failed as he appeared to be too tired to drink from his mother. When we measured his body temperature we wer - My first weeks as dad · On the challenges and rewards of being a father
Last Christmas my wife gave birth to our son, a little boy that would change everything! It's an incredible experience to become a parent, especially if it is your first kid. It introduces a whole new way of living, having to deal with regu - Business in a bag · Using a waterproof backpack to fit my gear
Over the past few months I have been testing different bags and cases to fit everything I need to run my business. As I commute by bike, the bag needs to be waterproof. The problem with waterproof gear is that it is usually very bulky. I ne - Do amazing things with a focused mind · Taking an ice bath and swimming in the Amstel river
Just when the temperature was a low 2° Celsius, I jumped in the Amstel river! While it was nearly freezing outside I went for a swim, just moments after I've taken an ice bath! This post is about the incredible birthday present I got, a wor - Around town in an electric car · Driving the Smart Electric Drive (EQ fortwo)
Earlier this month I drove around town for a week in an electric vehicle, a brand new Smart Electric Drive (EQ fortwo). I used it to commute, for my daily groceries and to visit family, friends and customers. What's it like to drive a fully - Is the Apple Watch the modern tool watch? · Testing the Apple Watch's usefulness in real life
This week I went to Frankfurt for business. I had to perform maintenance to servers in a data centre. This seemed like a great opportunity to test the Apple Watch's usefulness in real life (other than health and fitness). I wondered, is the - Rescuing files from a broken harddisk · Make backups to be safe rather than sorry!
Yesterday a young woman brought me her laptop, it didn't start anymore and it only showed an error message. It turned out to be a broken harddisk. It startled her when I told her that all data on the disk was lost. She told me it contained - Using a budget Android as main smartphone · Comparing a Nokia (€99) with an iPhone (€1329)
Every now and then, I switch phones to keep track of mobile developments. As professional app and web developer, I need to know how different devices work in real life. This time I used a budget Android smartphone, making me curious how it - Swimming and cycling with Apple Watch · Different activities in the workout app in watchOS
This month Apple launched a new Apple Watch series and released an update to watchOS. The focus of the smartwatch is more and more gearing towards health and fitness. This made me curious, how well does Apple Watch work for different activi - Optimising images for the web and performance · Reduce filesize with jpegoptim, optipng, pngcrush and pngquant
One way to make your website faster is to make it smaller. Not with tiny fonts, but with less bytes! More than half the weight of an average website is because of images. Yet very few people optimise their images for the web and performance - Space travelling from El Teide · Visiting Tenerife's volcano at the Canary Islands
This summer holiday brought me to Tenerife, part of the Canary Islands, Spain. It's a popular destination because of the climate, but it's also the home of Teide, the world's second highest volcano (7500 m, measured from the sea floor). The - Google Analytics vs AWStats · Understanding web traffic statistics software
This month I have been working on website statistics, tracking traffic using different technologies. Some of my customers use Google Analytics, others use AWStats, and some use both. Which is better is often debated, but few people really u - Helping people with free software · Installing Debian GNU/Linux on an old laptop
This week a man brought his laptop to the community centre where I help people with computer problems as volunteer. The old laptop wouldn't start anymore and had to be reinstalled. Instead of Windows, I installed a free operating system. I - Enjoy a festival without alcohol · Alcohol-free beer at Rock Werchter
Last weekend me and my brother went to Rock Werchter, a multi-day, music festival in Belgium. Over 140 thousand visitors enjoy world famous artists like Pearl Jam, Nick Cave, Artic Monkeys, Noel Gallagher, The Killers and the Queens of the - Removing paint from a bike frame · Uncover the aluminium with chemicals and sanding paper
There is beauty in raw, unfinished material that is often hidden with superfluous layers of paint. I like things to be true to the nature of the material. My bike was painted black - not bad - but I wondered what it really looked like from - Creating a minimal iPhone stand · Routing oak wood for a custom fit
Today I created a minimal iPhone stand from oak wood. While it's much faster to buy one online, I wanted one to fit my phone horizontally, with its case on. I like minimal design, so I opted to machine a single piece of wood to get it done. - Listen to your body · Why I stopped using health and fitness sensors
A good customer of mine was once a physiotherapist, he told me about people asking him to "feel their muscles" to tell them how they where doing. "Crazy!" he told me: "I can never feel better than the people themselves, if they only would l - Lunch by plane · Flying from Hilversum to Texel in a Tecnam P2002JF
This week I was invited to fly along over the Netherlands in a small aircraft, from Hilversum to Texel. A good buddy of mine is a pilot and planned to fly to the Texel island for lunch (and good fun!). The weather was excellent, so packed w - Off the grid: Working on 100% renewable energy · Collecting, storing and using solar electricity to power my phone, computer and wearables
For the past 10 days I have powered my personal electronic devices (phone, computer, wearables) using nothing but energy collected using a small solar panel. I disconnected all grid-connected chargers. I hoped that by going off the grid, ev - Outside the comfort zone: amateur acting · Wearing an heart rate monitor during my debut performance
This month I made my debut as amateur actor. I am no Hollywood star, nor do I envy to become one. But I do like crazy experiments and operating outside of my comfort zone often leads to new and refreshing insights. I took part in an amateur - Cyber security: 5 easy tips to protect your server against hackers · Server hardening best practices for Windows and Linux
This week one of my clients was hacked and asked me for emergency assistance to help secure their server infrastructure. It was a web server that ran WordPress websites on Apache (with PHP/MySQL), including a few webshops with customer data - Tablet as main computer · Comparing the Microsoft Surface Pro to iPad Pro
For the past few weeks I have been using the Microsoft Surface Pro as my main computer. It's a modern tablet computer that can be used as laptop with the type cover. With the Surface Pen, it's a versatile PC that works in a lot of different - Creating the ultimate commuter bike · Riding at 35KM/h with Nexus Alfine 8 and Gates Carbon Drive
This winter I use a Sensa Cintura bike with a Gates Carbon belt drive as my daily commuter. It's a bike designed to be nice to ride thanks to its sporty lightweight frame. It's also meant to be low on maintenance thanks to the belt drive an - Updating Snake '97 · About the challenges of developing a wildly popular game
Few years ago my brother threw a beer on my iPhone in an Amsterdam bar. The poor thing didn't like the Dutch brew as much as I do: it died. While waiting for a new phone to arrive, I used an old one that couldn't do anything but texting, ca - Something the smartwatch will never have: patina · Wear and tear by the hands of time
A good friend of mine had an issue with his Apple Watch, the digital crown lost a rubber ring causing the watch to lose its water resistance. Apple made no problem of it and offered to replace his "device". While it solved his problem, it f - Lessons from a takeaway plastic bag · My ever increasing antipathy to planned obsolescence
About five months ago I got some take away food from our local Asian restaurant. They packaged the food and gave me a plastic bag to carry it home. On my way home I was thinking about the bag. Although it has some nice styling printed on it - Commuting by bike · One week (240KM) on the VanMoof Electrified S
For a few years now, I commute to work using a bicycle. I have lost more than 15KG since I stopped using my scooter. This week I tested a VanMoof Electrified S, an electric bike with an industrial, minimal design. Is it any good? How does i - Collecting health data with Biostrap · Wearing a clinical-grade photoplethysmography (PPG) sensor for a month
Most wearables (smartwatches, fitness trackers, etc.) use very basic sensors to capture heart rate. Their signal is binary: just counting beats. Biostrap is different, instead of just checking pulses, it captures a high-fidelity PPG wavefor - From tree to table · Designing and creating a night stand
Right next to the house were I was born there was this chestnut tree, sadly it died one and a half year ago. When it was taken down, my brother saved me a slab of wood. I intended to create something from it, a nice "do it yourself" adventu - Saving a MacBook Air with exploded battery · Don’t try this at home - but I did
Last night I had a nasty surprise: my original MacBook Air was swollen due to an exploded battery. I immediately had to take action, for reasons of safety and to preserve this piece of modern computer history. Don’t try this at home, but i - Climbing Mount Etna · Visiting an active volcano on Sicily, Italy
Last week me and my wife went to Sicily for a little summer holiday. It is the largest island in the Mediterranean Sea. It is an autonomous region of Italy, along with surrounding minor islands. It's home to Europe's largest active volcano: - Clouds below my floor · Building a little datacenter in my basement
At my home I have this crazy fast optical internet connection. It is a 600MB up and down fibre connection which directly arrives in my home (no copper cables involved). It's like a private internet highway. Reason enough to find out if I co - The day I killed my LAN · Turned off my local network and went 4G only
Today I called my provider to quit my office's ADSL internet subscription, I don't need it anymore. I have turned off my local area network and switched my workflow onto mobile internet only. The simplicity and savings actually surprised me - Fietselfstedentocht 2017 · Cycling the 235KM bicycle tour through Friesland
This month I cycled the Fietselfstedentocht, a 235KM tour through Friesland. This tour brings you through various Frisian cities throughout one of the most Northern provinces of the Netherlands. The tour was first organised in 1912 and has - Beast of the Green Hell · Driving the Mercedes-AMG GT R
This month I received an invitation to join Mercedes at the Zolder circuit in Belgium to drive in "the beast". The Mercedes-AMG GT R, a furious green coloured performance car that gets its nickname from the Nürburgring where it was develope - Smartwatches vs Mechanical watches · Why I still wear mechanical and why smartwatches have potential
Technology has come a long way since the first computer. Smartwatches today are very much an achievement of miniaturisation of technology. I recently used an Apple Watch Series 2 to find out if technology has come far enough to replace my m - Repairing a Nintendo Gameboy Advance SP · Chip surgery to play classic Zelda
This month Nintendo released the Switch with Zelda "Breath of the Wild". The new console received positive reviews. The new Zelda game is amazing and can be played on-the-go, thanks to the portability of the Nintendo Switch. But it its hard - Programming on Apple Watch · Serious about crazy experiments
Over the past years I have been no stranger to crazy experiments, but this time I really wanted to push it into the extreme: programming on an Apple Watch. Would it be possible to actually write code on such a tiny device? Why even bother? - iPad Pro next to my primary machine · Using it with Apple Pencil as a creative powerhouse
I wanted see if I can find something better than my old fashioned pencil and paper that I use for designing software as professional developer. I knew iPad Pro from my test last summer, figuring out if it could replace my primary developmen - One year of cycling · GPS recording an entire year of bike rides using Garmin and Strava
One year ago I started recording all my bike rides, including commutes, short grocery trips and long Gran Fondos. I equipped my bicycles with Garmin Edge computers that recorded location (GPS), speed, cadence and my heart rate. I covered mo - Being a volunteer in Amsterdam-Zuidoost · Computer support in the local community center
After realising how lucky I am as an healthy, well educated, young man with a solid income, I wanted to do something for other people as volunteer. It just so happens to be that two years ago I received a flyer in my mailbox from the local - Harvesting boredom to let creativity flourish · using the Punkt MP01 dumb phone
Smartphones are everywhere in the modern society we live in today. Through our 4G and WiFi connections the internet is just one tap away. In fact, it is so close that it feels like a natural extension. But is this wealth of information all - Batavus Champion bike from 1978 · restoring retro glory with some help from the Internet
Almost a year ago I bought an old steel racing bike from 1978. I wanted to figure out if using a bike to commute worked for me. It did! I used it to ride more than 1000KM before I decided to get a modern road bike. Now, almost a year later, - iPad Pro as primary computer · testing iOS as primairy development platform
The lack of physical clutter, distracting branding, or blinking LED's makes the iPad Pro a textbook example of minimal design. My despiction of distraction explains my interest in using the iPad Pro as only computer to test if it is up to t - Cash is king, or is it? · The wallet- and cash-less experiment
Very often I see men carry a wallet filled with plastic: multiple debit and credit cards plus a bunch of loyalty programs and membership cards. Then, some even top it off with stinky paper money and sticky metal coins! It made me wonder if - Building the blog... in style! · Developing on a 20-year old computer with 16MB RAM and Windows 98
One must be a bit crazy to come up with the idea to build a blog (as in: actual programming) on an old 486 laptop with just 16MB RAM. I happen to be that crazy: I took my very first laptop from the 90s and decided to find out if it was poss