Plans
There are three ways to read the articles on this site. Free articles, and the abstract of every paid article, are free to read. What the paid plans carry is the record of the process that leads to those findings, and the long-form pieces that put the whole thing in order. All prices include tax. For what you can read, see What you can read; for who it is for, see Who this is for.
Articles are written in Japanese, and every published article also has an English version. Your plan covers both languages.
Sales are available in supported regions only; the Terms of Service list where we sell. All charges are in Japanese yen.
The free side alone is built to be enjoyable on its own. On top of that, if you want to satisfy your curiosity more deeply, if you want to trade impressions with other subscribers in the comments on an article, if you want to talk with matsumotory-kun and go further into the technical knowledge, or if you would like to support this work, a subscription has a fuller experience ready for you. If you feel like it, please do come along.
Samples you can read before choosing a plan
Before choosing a plan, you can read representative articles in full. Articles that are normally paid or subscriber-only are opened here for free.
Free
0 JPY
You can read the free development articles and the summaries of the key points of published research. For every paid article, the abstract with its conclusions and key numbers, the table of contents, and what you can take away are free to read. For the columns as well, the abstract that tells you what the piece is about is free to read.
To follow new articles you can use RSS. Articles that catch your eye can be saved to your favorites from the article page.
Standard
490 JPY / month
This plan lets you read every paid article, both the ones already published and the ones still to come.
On top of that, there are articles only Standard subscribers can read. From matsumotory's own day-to-day research and development, we pick what can be published here, analyze what actually happened without hiding either the successes or the failures, and write it up as knowledge from practice rather than theory. Each piece digs into what happened, what was tried, and how the call was made. Where the free and paid articles deliver the technical and research findings themselves, these articles deliver the practice behind them, the place those findings come from. The columns are not part of Standard; they are Premium-only.
You can also use the search that finds articles by meaning. Dialogue with Premium's matsumotory-kun is open to you as a trial of up to five messages a month.
To see what these records from behind the scenes are like, you can read the sample Developing solo with AI: what to entrust to outside services, and what not to own in full.
4 new paid articles ship every month, and 7 have been published so far this month. These four articles a month are the one promise kept even at the cost of other writing. You can cancel at any time, and after cancelling you can keep reading until the end of the period you have paid for.
You are currently subscribed to Standard.
You can change or cancel your plan in the customer portal.
You can switch to Standard in the customer portal.
Subscribe yearly at 4,900 JPY and you pay two months less than twelve months at the monthly price.
Premium
980 JPY / month
There are two headline benefits: you can talk with matsumotory-kun whenever you like, and you can read the columns, which are Premium-only reading. The dialogue limits are 30 messages a day and 400 a month. Everything Standard offers, with these two on top, is what this plan opens: the whole of this site.
matsumotory-kun holds this site's articles, and on top of them the papers, the two generations of blog, and the talk slides matsumotory has published so far, along with the fields he keeps surveying in his own day-to-day research and development. It thinks and answers in matsumotory's voice. Rather than searching the articles, the dialogue reasons on that knowledge, so you can bring anything from technical design to building an organization and career questions, the way you would ask a technical advisor. Standard gives you a trial of five messages a month, while with Premium you can use it without counting. For how it works and what it knows, see the section on matsumotory-kun on the about page, and for how external literature is handled, see the explanation of the data.
And the subscriber-only columns, which cannot be bought on their own and are not part of Standard, are Premium-only reading. They put into words, from practice, the new ways of thinking, the world that lies ahead, and how to work and live from here that have surfaced through many days of this work, with the worries and doubts left in. You can read them nowhere else.
To see what the columns are like, you can read the sample On the idea of turning myself into an AI, and where that leaves the one being overtaken in full.
You are currently subscribed to Premium.
You can change or cancel your plan in the customer portal.
You can switch to Premium in the customer portal.
One-time purchase
From 300 JPY per article
This is the way to buy paid articles one at a time. It suits readers who are not members yet and want to read just the one article that caught their eye. Each price is shown on the article's abstract page and at checkout. Deep long-form pieces can cost more than this.
Articles you have bought stay readable whenever you sign in with the email address used at purchase. Because of the nature of digital content, we do not give refunds after delivery as a rule.
To see what a paid article is like, you can read the sample Teaching my habits and values to an AI in full.
Paid articles you can read now
These are the paid articles published so far. A Standard or Premium subscription covers all of them, and a one-time purchase buys them one at a time. The abstract of every article is free to read.
- The failure of letting AI write the design rules first, and the fix that reversed the orderDated 2026-07-16Published 2026-07-22
Single purchase 300 JPY
- Building search for a membership site as two tracks, free and paidDated 2026-07-14Published 2026-07-14
Single purchase 300 JPY
- Teaching my habits and values to an AIDated 2026-07-11Published 2026-07-11
Single purchase 300 JPY
- I didn't call it done after fixing where entrusted API keys leaked; I handed the defense to the codeDated 2026-07-08Published 2026-07-09
Single purchase 300 JPY
- The more rules I added for the coding bots, the less they followed them, so I stopped adding rulesDated 2026-07-08Published 2026-07-09
Single purchase 300 JPY
- I built evaluators that don't pass what they can't judge, in two separate placesDated 2026-07-08Published 2026-07-09
Single purchase 300 JPY
- In two apps of completely different natures, what decided the search strategy in the end was measurementDated 2026-07-08Published 2026-07-09
Single purchase 300 JPY
Common terms
For each article, which parts matsumotory wrote and which parts the AI wrote are deliberately not disclosed. The details of the conditions are in the Terms of Service and the Legal Notice. How the site is operated and how it earns is published in the Operating and revenue disclosure.