Jens Oliver Meiert
Articles and books on the craft of web development, with a focus on HTML and CSS minimization and optimization.
48 Laws, Rules, and Principles of Web Development
In anticipation of the upcoming release of The Web Development Glossary 3K, here are four dozen laws, rules, and principles related to web and software development.
HTML Concepts: Kinds of Elements
There are six kinds of elements in HTML: void elements, raw text elements, escapable raw text elements, the template element, foreign elements, and normal elements.
Website Issues: On the Relevance of Audience Size and Impact
Website issues—relating to conformance, security, accessibility, performance, content, others—are usually treated with a particular priority, but that priority may not always be understandable, and may also be off. On the perspective we obtain when we consider and chart audience size and impact.
CSS Naked Day and the Lost Wikipedia Page
CSS Naked Day has a message—separation of concerns. The event has been around for nearly 20 years, thousands of developers have participated, and it’s still alive. It may not be an event significant enough for Wikipedia, for which this post had been a draft—but it does seem significant for our field.
Two Underused Arguments for Writing Documentation
Validating our thinking and allowing to scale may not get enough attention.
On Ageism
One may argue that the big “-isms” go back to speciesism, the idea that one was “better” than other living beings, or that others were inferior. With that idea warranting a post by itself, there are two things that make ageism particularly stupid.
Highlights from “The Social Contract” (Jean-Jacques Rousseau)
“The strongest is never strong enough to be always the master, unless he transforms strength into right, and obedience into duty.”
Highlights from “The Protestant Ethic and the Spirit of Capitalism” (Max Weber)
“The modern rational organization of the capitalistic enterprise would not have been possible without two other important factors in its development: the separation of business from the household, which completely dominates modern economic life, and closely connected with it, rational book-keeping.”
HTML Concepts: Customized Built-In Elements
HTML allows to define custom elements, elements which enable authors to “build their own fully-featured DOM elements.” One special type of custom element is the customized built-in element—a custom element built on an existing HTML element.
Website Optimization Measures, Part XVIII
Random improvements as always, this time covering ARIA roles, Apache module checks, <guid>
elements, CLS rules of thumb, Eleventy, block lists, site licenses, and compression settings.
Conformance and Accessibility
The Web Content Accessibility Guidelines 2.2 are going to obsolete Success Criterion 4.1.1, which had been WCAG’s nod towards conformant HTML output. This is understandable, and it may even be good—to strengthen accessibility as well as conformance.
Speed Up Your Org: When to Require Approval
Organizations can be slow. One thing that makes them slow is process. One part of process consists of approvals. But approvals aren’t always needed. On default answers, and the severity and probability of failure.
My CSSÂ Wishlist
Trim it.
26 Additional Web Development Terms You May Not Have Heard Of
Web Development has its own, special vocabulary that consists of several thousand terms. No one knows all of them. (Or do they?) Here are 26 more terms you may or may not have heard of—perhaps including AAAA or MAM or YMYL.
Challenge Yourself, Even When It’s Art
The paradox of CSS art may suggest an artist had a free pass for the quality of their code. Or does it? I believe there are three possible answers to this.
2022
Release of my next book, a new apartment in downtown Hamburg, good news from the football club, a political adjustment, some travels, and preparation for a professional change—some of my highlights in 2022.
A Problem With Link Relationships
It’s easy to get excited about link relationships and similar types of metadata. But link relationships are invisible information, and some invisible information is notoriously hard to maintain—especially on things that decay, describing attributes that change.
A Brief History of UITest.com
UITest.com just merged with Frontend Dogma, which is asking for select and random screenshots and facts about a site that I ran for 19 years to provide “web-based and free tools for web development and design.”
Website Optimization Measures, Part XVII
Encoding declarations. Conditionals. Ahrefs. ErrorDocument
directives. Mastodon links. Mastodon citizenship. Bitbucket. Eleventy. Action.
The Reverse A-Hole Rule of Social Media
A delayed note about that point at which our defense against disagreeable viewpoints and people becomes an offense.

Upgrade Your HTMLÂ IV
HTML forms the heart of the Web. The beautiful thing is, HTML is easy to learn. Unfortunately, it’s difficult to master. In the Upgrade Your HTML series, I’m taking examples of HTML, discuss these examples, and make them a little better. I’m excited to announce the fourth book of the series.
HTML Concepts: Unstyled Documents
There’s unstyled and there’s fully unstyled. And then there’s also styled “in a manner that is useful for a developer.”
Website Optimization Measures, Part XVI
Spaces, HTTP headers, site generator exports, cite
elements, variable fonts, social logos, no-break spaces, metadata—life is never boring when you run your own websites.
10 Quick Tips for a Great Mastodon Experience
Mastodon is a great alternative to Twitter, feeling refreshingly healthy. Here are 10 things that can help you get off to a great start—from finding a suitable server and interesting people to follow, to useful tooling and mindsets.
Minimal Dark Mode
What’s the easiest and fastest way to set up dark mode? Depending on the setup, something from one declaration to two rules.
About Me

I’m Jens, and I’m an engineering lead—currently manager for accessibility at Miro—and author.
In web development, I specialize in HTML and CSS, contribute to technical standards, and write books (like The Little Book of HTML/CSS Frameworks, On Web Development, CSS Optimization Basics, the Upgrade Your HTML series, and The Web Development Glossary).
I love trying things: In philosophy, I’m interested in metaphysics (even in How to Work on Oneself). When it comes to art, I play with photography. And for adventure, I enjoy exploring places (Journey of J.) and activities (100 Things I Learned as an Everyday Adventurer).