Developing a New Headless CMS Vol. 1
Want to run a blog on a custom domain with your own design? Kurousagi has started developing KuroCMS, a new headless CMS designed for the AI era.
I have been using Strapi, an open-source headless CMS that you can set up yourself, for about four months. While it is a very good software, I had the impression that it was originally built for the English-speaking world and didn't pay much attention to multilingual support, and it is difficult for computer beginners to use. So I decided to develop my own.
A Headless CMS, Yet Extremely Easy: The Birth of KuroCMS
Since I couldn't find a headless CMS in the market tailored for the niche demand of wanting to start a blog with one's own domain and custom design, I decided to develop a headless CMS that represents my ideal in the AI era.
The name is KuroCMS, since it is Kurousagi's (Black Rabbit's) CMS. Please don't say it's too simple, haha. Even when I was writing novels, I knew I lacked a sense of naming. That said, I would like to write about the development of KuroCMS in several articles according to the progress.
What is a CMS in the First Place?
A CMS (Content Management System) is a system that allows you to create, update, and manage websites without specialized programming knowledge like HTML or CSS. You can easily add and modify pages just by entering text and images into the admin panel. And when people think of CMS, WordPress holds such a high share that it is synonymous with it, but setting it up yourself is hard, and in Japan it is common to use free blogging services. Here are the major free blogging sites:
Ameba Blog (Ameblo)
Item | Content |
Overview | One of the largest general daily life and community blogs in Japan |
Main Genres | Celebrities, parenting, daily life, lifestyle |
Main User Base | Women in their 30s to 50s, housewives, celebrities |
Share & Scale | Overwhelming recognition as a domestic blog |
Monetization | Ameba Pick (original affiliate program) |
Editor | Visual editor for beginners with easy decorations |
SEO (Search) | Centering on internal circulation; average for Google Search |
Hatena Blog
Item | Content |
Overview | An all-round blog strong in SEO and reader community |
Main Genres | Hobbies, otaku culture, current events, IT |
Main User Base | Men in their 30s to 40s, businessmen, IT professionals |
Share & Scale | A major blogging platform with persistent loyal fans |
Monetization | Free affiliate ads, Google AdSense |
Editor | Diverse editing modes (Hatena notation, Markdown) |
SEO (Search) | Custom domain available. SEO is extremely strong. |
note
Item | Content |
Overview | A writing and content sales SNS for creators |
Main Genres | Essays, business, creations, development stories |
Main User Base | Creators, entrepreneurs, writers, general public |
Share & Scale | Rapidly growing, surpassing 10 million members |
Monetization | Paid articles, paid magazines, memberships |
Editor | Extremely simple and clean unique editor |
SEO (Search) | Strengths in SNS sharing rather than single search targeting |
Qiita
Item | Content |
Overview | One of the largest knowledge-sharing sites specializing in engineers in Japan |
Main Genres | Programming knowledge, environment setup, error solving |
Main User Base | Corporate engineers, programming beginners |
Share & Scale | The top technical site with over 1 million members |
Monetization | No direct monetization for individuals (corporate PR only) |
Editor | Markdown support; easy-to-read code blocks |
SEO (Search) | Domain power is at the strongest level; immediate high ranking |
Zenn
Item | Content |
Overview | A technical media strong in modern technologies and writing books |
Main Genres | Practical programming, personal development, tips |
Main User Base | Engineers loving modern technologies, indie developers |
Share & Scale | Lately gaining momentum, approaching Qiita in the tech community |
Monetization | Selling paid books, badges (tipping) |
Editor | Markdown support, GitHub repository integration |
SEO (Search) | Strong in technical keywords with rich search traffic |
Using these services is the easiest and most convenient option, but you must construct your site following the format of that service. It is also true that your freedom is restricted if you want to use your own domain, custom design, or build your own monetization system. That is why headless CMS was born.
What on Earth is a Headless CMS?
Simply put, free sites also run like a headless CMS internally to provide services. The comparison with WordPress used to be easy to understand, so I had AI create a diagram.

In short, separating the appearance from the data management allows you to use data in various forms. Therefore, it is useful not only for blogs but also for product sales, corporate news, and other pages.
By now, I think you have a basic understanding of terms and types of services. Based on this knowledge, I will explain KuroCMS, the headless CMS provided by Kurousagi, in detail starting from the next article.