Articles & field notes
Psychology, experimentation, community building, AI workflows, open tech and homelabbing: what I'm learning, mostly in the open.
Outsource your GitHub CI to a VPS: cheaper, faster, and a free backup server too
Self-hosted GitHub Actions runners on a small Hetzner VPS cut my CI wall-clock from ~12 minutes to ~3 minutes for about half the price of the GitHub-hosted minutes I was burning. Here's the full setup.
Make links to your blog render the custom "View publication" card + CTA
Short guide. The mechanism is simpler than it looks, and it doesn't involve any /.well-known file or DNS TXT record.
ATmosphere Conf 2026: the internet built for people, not platforms
370 people in Vancouver, 500 online, all working on the same question: what does the internet look like when users own their data? Highlights from the AT Protocol community conference.
Running Doom over the AT Protocol
Every keystroke becomes a record. Every frame becomes a blob. A technical walkthrough of making the AT Protocol do something it was never designed for.
AI slop is drowning communities. Verifiable track records can fix it.
AI-generated junk content is flooding every community platform. Traditional moderation can't keep up. Portable, cross-platform contribution history is a structural fix that addresses the root cause.
Barazo: community forums where members own their data
I'm building an open source forum platform on the AT Protocol. Members log in with their Bluesky account, posts live on their own data server, and reputation follows them across communities.
Better Not Waste It
A story about token limits, AI companions, and the sunk cost of unused mana.
BigTech independence update: cleaning house for local AI
Three months after my original BigTech independence article, here's what changed and why I'm building infrastructure for local AI.
A practical guide to building your own antifragile tech stack
Seven principles for evaluating technology choices, reducing vendor lock-in, and building a more resilient digital setup. The decision-making framework behind the tools.
Start building Anti-Fragile communities, your community deserves it
Over 20 years building communities around open-source platforms, I've watched a pattern repeat. Communities feel invincible until the moment they collapse. Learn how to build anti-fragile communities that gain strength from change instead of breaking under stress.
Ditching "One community idea per month": Our hackathon path to 80+ community projects
Learn how we transformed community engagement through hackathons instead of monthly idea quotas, creating 80+ community projects while building better understanding between community and product teams.
How I reduced my BigTech dependencies in 2025 (and why you should too)
A detailed guide on moving away from vendor lock-in and Big Tech subscriptions to build a more robust, privacy-friendly, and antifragile tech setup using open source alternatives.
RPi Pirate audio side project
Building a custom audio project with Raspberry Pi and Pirate Audio hardware - a fun side project exploring hardware and software integration.
7 Hard-(l)earned lessons for building reliable AI workflows
Practical insights and lessons learned from building and deploying AI workflows in production environments.
The Collapse of Traditional Commerce - Why Innovation is No Longer Optional
Explore how traditional commerce models are being disrupted and why businesses must innovate to survive in the rapidly evolving landscape of global commerce.
Concerns with AI programming
An analysis of the potential challenges and concerns surrounding AI in software development over the medium to long term.
4 options to customize your LLM
Explore four great ways to customize Large Language Models for your specific use case, from prompt engineering to fine-tuning and RAGs & MCPs.
Website moved to Astro
After almost 7 years, it was time for another switch: Moved the website from Webflow to Astro.
The Art of Clear Messaging at Trade Shows - What We Can Learn from Food Trucks
How food trucks master clear, instant communication and what trade show exhibitors can learn from their approach to messaging.
Beyond Code: Software Developers in the Age of AI
Exploring how software developers can adapt and thrive in an era where AI is transforming the development landscape.
Why Every Moment Looks Like a Turning Point in Exponential Growth
Discover why exponential growth charts can be misleading and why "today" isn't a special turning point despite what many trend analyses suggest.
How to Build an Online B2B Community
Learn how to create and maintain a successful B2B community, overcome unique challenges, and leverage the benefits for your business growth and customer engagement.
Often Confused Commerce Terms
Let's set the record straight about some often mixed up terms in commerce
Optimization hierarchy of evidence
A CRO/Experimentation variant of the scientific hierarchy of evidence
Are you LEFT or RIGHT brain? Surprise: you're both
You've probably heard about this divide between the functions of the Left Brain versus the Right Brain. There is no divide.
The Story of Spryker with CEO Boris Lokschin
Building the commerce platform of the future
First episode of CRO.CAFÉ is live!
As announced in November I would be starting a new (Dutch) podcast series this year about CRO. Today the first episode launched!
Recording: Creating An Optimization Culture
Recording of my session about creating an optimization culture
Website moved to Webflow
Amazing new visual SaaS CMS system!
Can you afford not to know? Can you afford to be wrong?
How far do you go? What do you test? And is it sometimes ok NOT to test something?
Texas sharpshooter fallacy
To help remember statistical constructs I've started telling stories about statistics and the first one is about the Texas Sharshooter
Data Driven Decisions meets Psychology
On October 24th, I gave a session at Nomad Mage about using psychology and data to make the decisions to improve your webshop.
New domain and CMS!
Switched to gui.do and Grav CMS
Questions on Experimentation
Designing great experiments
Learnings from Shenzhen
Some (random) notes/learnings from my trip to Shenzhen China
Proving the monetary value of A/B testing
How to go from “4% conversion uplift” to “€636K — €854K extra profit this year”
The CRO Process
White-paper on the CRO Process
Intervju: Guido Jansen ska ta reda på varför kunderna inte handlar
This is a re-post of an interview with me by the Swedish magazine eHandel
Combining personal & business online: 5 guidelines/tips.
My 5 tips on building your personal brand by having a healthy personal + business presence on your social media channels.
Compute required Sample Size for your A/B tests
Google Sheet calculator for your AB test sample size
Trustlogo onderzoek
Dutch Research towards e-commerce trust logo's
How Color Persuasion Works
How to (not) use colors in your website
One year .com in retrospect
One year ago, I moved my blog to a .com
Persuasion profiling: Dawn of a New Marketing Era
PersuasionAPI: A new tool that makes your website much more persuasive
Update: 101 ways to optimize Magento for speed
Guess Magento and it's speed is a hot issue :).
101 ways to speed up your Magento e-commerce website
Let's optimize your webshop for speed!
Top 8.5 tips for getting started in ecommerce
For business owners that have a retail store or a complete new business model but have little to no experience in the e-commerce field: this post is for you.\
9.999 on 09.09.09 09:09
Fun coincidence!
New Website Online
Created a new website based on Mambo CMS
Website Online
My first personal website!