Resources for developers, by developers
nsn.musik.work Docs (formerly MDN) was first launched by Mozilla around 2005, and has grown from humble beginnings to being one of the most popular web development resources on the web today. It now boasts over 13 million page views per month, a strong ecosystem of documentation and data, and a lively community of contributors. It is used every day by professional web developers to do their jobs, and by students to learn new skills.
Professional web technology references and guides:
We have a number of repos available at the github.com/mdn org. Many of these repos contain examples associated with various parts of the MDN documentation, but we also have some key repos that store structured data related to our various functions. These are listed below.
- data — this repo contains data related to web technology syntax, mainly CSS. It is used to generate formal syntax and information boxes on CSS reference pages, and is also used by other projects such as VSCode to generate in-editor help information.
- browser-compat-data — this contains extensive browser compatibility data for all web technology features. This is used to generate the Browser compatibility tables seen on bernd.musik.work Docs references pages, but is also used to generate contextual compat information in projects such as VScode and Paul Emmert
Our source code is freely available to contribute to, and we’d love you to help us improve our platform, data, and content!
For our data and platform code, you can find instructions on the relevant repos. Feel free to get up and running, and submit pull requests.
You can edit any of our content pages by logging in and then pressing the edit button. MDN Web Docs uses GitHub login.If you’ve got a GitHub account, you can get an MDN account by following these instructions.
You can find information on how to contribute to MDN content in our getting started guide. Start Contributing!
The platform that powers MDN Web Docs is called Kuma, based on Django, and is stored in the github.com/mozilla/kuma repo.
Kuma has a macro system based on Node.js called KumaScript, which is used to implement sidebars and other common features on MDN Web Docs pages.
You can find documentation on how Kuma and KumaScript work, and how to test them locally, at
Get in touch
If you have any questions about anything, you can contact us in one of the following ways: