Hello and welcome! Here I occasionally post about making digital products.
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You're making me buy a new phone
I don't want a new phone, but I'm probably buying one.
How to make volunteer-driven open source projects successful
Free and open source projects could be much more successful for you and your users!
Why is open source software so badly designed?
It's not just a matter of developers acting friendlier or designers acting less egoistically.
The future of blogging
Good things are coming to the web!
Blogging or posting on social media—what's better?
If you were to start sharing ideas today, what channel would you pick?
Design and art
How one phone call made me give up my dream of becoming an artist and made me see twenty-five years later that design and art aren't that different.
I sold Big Timer
Did I make the right choice selling my side project?
The new heroes of design
They're not larger than life. Sometimes I disagree with them. I don't even like some of their work.
A not so gentle intro to web3
You're not too stupid to understand what's going on.
New Year's resolutions are silly
Here's the template I use to get to achieve what I want instead.
I designed a Christmas gift
You can get this sustainable gift too!
Do you really need to set a theme color to color Safari's UI?
Probably not, but you may want to do it for Android users.
Bringing markers back to UI design
Here's something to make Figma play nice with paper freehand sketches.
There are no individual contributors in design
It's time for this term to join 'outside the box', 'big data' and 'hit the ground running' in history.
How I replaced doom scrolling with productive media routines
The best way to stop a bad habit is to replace it with a new one.
Here's how I maintain healthy media routines (most of the time)
Developing good routines can be more important than stopping bad habits.
Breaking unhealthy media habits in six simple steps
Here's what I did to lay off habitually checking news feeds.
10 Reasons why bicycles can't replace cars
Reasonable people have reasons for not to using their legs to pedal and using a car instead.
Sidenotes can make a plain text richer. Here's how you can implement them with HTML and CSS alone.
Design better by avoiding your cognitive biases
Can you outsmart your brain? Seven biases that mess up your designs and what you can do against them.
Making a multilingual website with Jekyll collections
A foolproof and flexible way to add translations to a Jekyll site.
Getting to know utility-first CSS
The atomic approach to writing CSS is awesome—with caveats.
The pandemic, racism and climate change: Let's fix everything
I don't want to go back to normal.
Mass surveillance won't stop corona. What can tech do though?
Mass surveillance is not useful to stop the corona virus pandemic. We can prepare ourselves for the next pandemic though.
Semantic sidenotes for the web
Sidenotes have been around for ages in print, but they're surprisingly hard to do well in HTML.
The dangerous mix of optimism and innovation
Does optimism make you dumb?
A guide to implementing dark modes on websites
Don't just add a dark mode because iOS 13 supports it now.
This website is now monetized
Don't worry, I didn't put up ads.
Adding comments to my static website
How I choose a commenting system
Can we improve products by making them less efficient?
I think so!
Picking up longboarding as a grown-up
Recommender system basics: Part 2
What designers should know about recommender systems
Recommender system basics
What everyone should know about online recommendations
User-centered versus user-centric design
This is bigger than modernism versus post-modernism.
What is design?
What is design, in one sentence? Thinking about the moral responsibilities in design, I need a precise definition.
6 Questions all experienced designers should be able to answer
6 Questions I don't have an answer to
Dark mode design considerations
Implementation is easy, but how to design a dark mode?
Do I have to add a dark mode now?
Reasons for and against adding a dark mode to an app or website.
Why color discussions can be so frustrating and 3 things you can do about it
Win all arguments about color! Or: why you may actually not want to.
How we all see colors differently—Color theory in design
Do you see that color in your mind the same way I see it?
Multidimensional responsive design: 5 tips
About layouts that are responsive to more than just horizontal breakpoints.
Making custom fonts: how and why
Creating a custom font was easier then I thought it would be!
Replace social media with blogs and RSS?
Three reasons why I like that idea.
Sketch, Figma, Adobe XD, UXPin or InVision Studio: which one?
I did a detailed comparison to find out what screen design tool is best for what.
Four ways screen design tools can be improved
Because bad tools can lead to bad design processes.
Interoperability between UI design tools
I’m in the process of comparing UI design tools: Sketch vs Figma vs Invision Studio vs Adobe XD. When considering to migrate from one to...
Brutalism is not great for looking relatable
Last time I wrote about how brutalism is the only design movement in which personal websites play an important role. Brutalist architecture, however, is mostly...
Broken or brutalism: personal websites in 2018
About modernism, capitalism, brutalism and finding my personal online identity
Hey Koos, do you still recommend WordPress?
My website is falling apart. Not what you see right now though, although it may look like it. I mean the previous version, that is...
Things I learned from doing a side project
I have a job as a designer at BCG Digital Ventures. There we create new businesses: we find out about problems that people have, then...
Why side projects fail
So, my side projects fail! Let me first describe what I would consider a successful side project. A side project is something: That is fun...
What is color?—Color theory in design
Choosing colors depends often on the designer’s taste. This can lead to tough discussions with stakeholders that do not share that taste. Everyone has gut...
How I design ‘mobile first’
Some things I wrote way back when mobile first were just buzz words.
New design pattern: Drag To Tag
Working on a new platform for keeping annotations, I came up with a new way of tagging items!