Christian Heilmann

Web Development according to Grok is all about libraries…

September 12th, 2025

Cleaning out some old boxes trying to find an old work contract I came across a sticker sheet I got back when HTML5 became a standard that has all the icons on there the W3C defined as part of the “web reboot”: I posted it around on social media to see who can remember them […]

A CSS only time progress bar to use in markdown / GitHub Pages

September 5th, 2025

For our weekly WeAreDevelopers Live Show I wanted to have a way to include a time progress bar into the page we show. The problem there was that these are markdown files using GitHub Pages and whilst I do use some scripting in them, I wanted to make sure that I could have this functionality […]

Returning to the US: see you at All Things Open 2025

September 1st, 2025

When I still worked for a US company, I traveled every few weeks to the US, so much so that I had gold status on several airlines. Ever since the Covid pandemic hit and I got laid off by my last employer as part of a 10k employee cut, I stuck to Europe. Other reasons […]

A lesson from history for Software Engineers, Product Owners and CEOs

August 22nd, 2025

This is the U-1206. It was the peak of submarine technology at the end of the Second World War. Right now it lies at 70 metres depth slightly North West of England. You might say this is an impressive feat for a submarine to be submerged that long. Alas, it is isn’t by design but […]

Using GitHub Pages as a URL shortener / redirection service

August 11th, 2025

With the fate of Goo.gl in the balance and many URL shortening/redirection services being either expensive or spammy, I wondered if I could find a free/cheap way of achieving the same. So I got myself a short domain (CLXI.org) and looked at using a GitHub repo with pages to redirect URLs. Turns out, this is […]

Newsletter

Check out the Dev Digest Newsletter I write every week for WeAreDevelopers.

Don't stop thinking, AI Slop vs. OSS Security, rolling your own S3 Despite AI you still need to think, Bitter lessons from building AI products,  AI Slop vs. OSS security and pointer pointer…
200: Building for the web, what's left after rm -rf & 🌊🐴 vs AI What remains after you do a rm -rf? Why do LLMs know about a seahorse emoji? What image formats should you use? How private is your car?
Word is Doomed, Flawed LLM benchmarks, hard sorting and CSS mistakes Spot LLM benchmark flaws, learn why sorting is hard, how to run Doom in Word and how to say "no" like a manager.
30 years of JS, Browser AI, how attackers use GenAI, whistling code Learn how to use AI in your browser and not on the cloud, why AI makes different mistakes than humans and go and whistle up some code!
197: Dunning-Kruger steroids, state of cloud security, puppies>beer

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