Agent Skills: Stop Stuffing Workflows Into Your Rules File
Salatiel Lima | Apr 29, 2026
Summary
- The article begins a series on building a web browser, with part 1 focused on specifications rather than code, arguing that defining how software should work is harder than executing it.
- W3C was the main web standardization body until 2004, when WHATWG formed (Mozilla, Apple, Opera) in response to W3C's pursuit of XHTML2, proposing HTML5 and a 'living standard' model of continuous updates.
- Browser vendors sometimes implement features without sharing specifications, such as Apple's window.orientation, which harms the open web and forces others to spend effort on compatibility.
- In 2015, W3C launched the Web Platform Incubator Community Group (WICG) to make it easier for developers to propose and discuss new platform features before formal standardization.
Browsers are a complex piece of software: inside a web browser there are features comparable to a whole operating system. Every time I googled how to make a web browser, the answers were quite shallow, usually talking about how to consume some browser engine and make something on top of it. This article aims to walk through the whole process of making a web browser. On part 1, I’m going to talk about specifications.
In my lifetime experience as a developer, I learned that executing the code is usually the easiest part of the software development process. What really takes time and effort is defining how it should work. That’s what organizations such as the W3C and WHATWG do.
The W3C — World Wide Web Consortium — is an international standards organization, which maintains full-time staff for the purpose of working together on the development of standards for the web. Until 2004, the W3C was the main responsible for standardizing the web.
To this day, most new features required long periods of time for standardization, followed by implementation by many browser vendors, only then followed by developer feedback and iteration. But this workflow is changing…
In 2004 an organization formed by Mozilla, Apple, and Opera Software named WHATWG — Web Hypertext Application Technology Working Group — was born in response to the W3C wanting to pursue XHTML2 — which had no interest from browser vendors. Their proposal was to evolve HTML, rather than invest in XML based technologies, this evolution is known today as HTML5.
WHATWG proposes a different way of thinking specifications, they call it a living standard:
This means that they are standards that are continuously updated as they receive feedback, either from Web designers, browser vendors, tool vendors, or indeed any other interested party. It also means that new features get added to them over time, at a rate intended to keep the specifications a little ahead of the implementations but not so far ahead that the implementations give up.
But not every feature comes from a standardization group. Sometimes, browser vendors implement a feature needed for its own business and never share a specification with the community. This practice is harmful to the health of the open web and forces browser vendors to spend energy on compatibility, rather than innovation.
If you read this link, you’ll see it is a specification document for window.orientation, a feature created by Apple that never really got specified anywhere, so Mike Taylor wrote a spec for it. Actually, if you take a good look at the previous link, you will see that the whole document is about documenting non-standard features so all browsers can be compatible.
But as I mentioned before, things are changing, the community is becoming more mature and the process is getting better. Today it is a lot easier to play a part in the web evolution.
In 2015, W3C launched a new working group called Web Platform Incubator Community Group (WICG). The purpose of the WICG is:
- Make it as easy as possible for developers (like us!!) to propose new platform features, in the spirit of the Extensible Web Manifesto.
- Provide a space where developers and implementers can discuss new platform features.
- Incubate those ideas by providing guidance and a supportive and inclusive environment to those who have never contributed to standards (and even to those that have!:D); ultimately transitioning those ideas to a W3C Working Group for formal standardization (i.e., making a “W3C Recommendation”).
- Modernize how we do standardization of platform features
- Provide a legal framework that keeps all contributions free and open.
Now you know a little bit more about this process, you can probably understand why some things aren’t the way you expected to be or why some features take so long time to land and stabilize.
If you feel like adding your bit to the web, here are a few specification links for important building blocks of the web:
WHATWG — https://github.com/whatwg — html5, fetch, dom, compat
WICG — https://github.com/WICG — ResizeObserver, EventListenerOptions, webusb, BackgroundSync
W3C — https://github.com/w3c — ServiceWorker, css-houdini-drafts, webcomponents
Don’t be like Apple, don’t forget to share 😉
Special thanks to Mike Taylor for the support writing this article and for doing a great and inspiring job.
FAQ
What is the W3C and what role does it play in web standards?
The W3C — World Wide Web Consortium — is an international standards organization that maintains full-time staff for the purpose of working together on the development of standards for the web. Until 2004, the W3C was the main responsible for standardizing the web.
What is WHATWG and why was it formed?
WHATWG — Web Hypertext Application Technology Working Group — was formed in 2004 by Mozilla, Apple, and Opera Software in response to the W3C wanting to pursue XHTML2, which had no interest from browser vendors. Their proposal was to evolve HTML rather than invest in XML based technologies, an evolution known today as HTML5.
What is a 'living standard'?
A living standard is the way WHATWG proposes thinking about specifications. It means standards are continuously updated as they receive feedback from web designers, browser vendors, tool vendors, or any other interested party. New features get added over time, at a rate intended to keep the specifications a little ahead of the implementations but not so far ahead that the implementations give up.
Why is it harmful when browser vendors implement features without sharing specifications?
Sometimes browser vendors implement a feature needed for their own business and never share a specification with the community. This practice is harmful to the health of the open web and forces browser vendors to spend energy on compatibility rather than innovation. An example is window.orientation, a feature created by Apple that was never really specified, requiring Mike Taylor to later write a spec for it.
What is the WICG and what is its purpose?
The Web Platform Incubator Community Group (WICG) was launched by W3C in 2015. Its purpose is to make it as easy as possible for developers to propose new platform features, provide a space where developers and implementers can discuss them, incubate ideas with guidance in a supportive and inclusive environment, ultimately transitioning those ideas to a W3C Working Group for formal standardization, modernize how standardization of platform features is done, and provide a legal framework that keeps all contributions free and open.
About the author.
