この場所の仕組みは、ひとりでつくりました
つくった人と、 仕事のご相談
予約と決済、AIチャット、玄関のキオスク、カメラとセンサー。標高1,444mのこの場所を動かす仕組みは、仙人けんじ(Kenji Sakuramoto)がつくって、毎日動かしています。同じものを、あなたの施設にもつくります。
仕事の相談をする
How he got here
Sennin Kenji (Kenji Sakuramoto), founder of kensaurus. IT consulting, cyber security and app development through his 20s and 30s. He renovated a closed farm rest stop at 1,444 m and opened this place on 8 August 2026. Grass cutting, septic tanks, a mountain winter: all new. He also takes on consulting, development and photography.
More about Sennin Kenji一本の線で、ぜんぶつながっている
お客さまがサイトを開いてから、玄関のドアを開けるまで。その線の上に、こんな仕組みが並んでいます。
The booking site
The site you are reading. Guests check what is free in Japanese or English, then book and pay on the spot by card, Square or PayPay.
道具 React 19 · TypeScript · Vite · Supabase · Stripe · Square · PayPay
One AI, four doors
The site chat, LINE, the tablet by the door and the door voice: the same AI answers from the same data as the price list, and hands what it cannot answer to Sennin Kenji.
道具 Claude · LINE Messaging API · Supabase Edge Functions · Langfuse
The kiosk at the door
An Android tablet at the door does the front desk’s job. The app updates itself over the air.
道具 PWA · Android · OTA
The site monitor
Seven cameras, temperature and water-level sensors, power plugs and the network on one plan of the site. AI tells people from cars, and the recordings can be replayed.
道具 Frigate · OpenVINO · SwitchBot · Ecowitt · Omada
Read how the site monitor was built (kensaur.us)
牧場モニターの実際の画面 The console
Bookings, the shop, Wi-Fi codes and the ad numbers on one screen. Staff alerts arrive on Discord.
道具 Supabase · Discord · GA4 · Google Ads · Meta
Signs and print
Posters, flyers, name cards and the signs on site come from the same price data as the site, so print never disagrees with it.
道具 React · Playwright · PDF
Security, and the day something breaks
Every change goes live only after tests and automated checks pass. The database is locked down row by row, and there are written steps and spares to bring the on-site PC back if it dies.
道具 GitHub Actions · Playwright · semgrep · gitleaks · Sentry

牧場モニターの実際の画面
数字で見ると
- 3,030
- changes shipped since December 2025
- 85
- server functions
- 964
- database migrations
- 7
- cameras on one screen
2026.10.30時点。コードから数えた値です。
お金は、いちど入力するだけ
I used to type the same money into three apps.
Tsumagoi Work&Camp
Sales, payouts, stock and the daily close. It writes accounting batches at each close and every night.
一人社長 Solo Boss
Pulls those batches every hour and books them as draft journal entries. Nothing reaches the ledger until they are approved.
yen-yen
Sends business costs paid on a personal card to Solo Boss as 立替 claims, and gets their status back.
We can build this kind of link between your apps.
ほかにつくったもの
Bookkeeping through to tax filing, for one-person companies
This place's accounting flows in here as draft journal entries.
solo-boss-cloud_backend 一人社長 Solo Boss — AI legal, tax & accounting advisor for Japanese solo entrepreneurs. Backend API: Express 5 + Prisma + Supabase/PostgreSQL, multi-LLM (OpenAI/Claude/Gemini), NTA/e-Tax/eLTax integrations.
solo-boss-cloud-documentation 一人社長 Solo Boss — AI accounting & tax advisor for Japanese solo entrepreneurs. Frontend: React 19 + Vite + Tailwind PWA (also iOS/Android via Capacitor).
A shared household money book, no bank login
Business costs paid personally go from here to Solo Boss.
yen-yen kakeibo-inspired cloud budgeting app for iOS, Android, and the web
A report-a-bug button for apps, with AI that sorts the reports
mushi-mushi Know why your AI-built app broke — plain-English diagnosis + ready fix, in your editor. Open source. Sentry optional.
A Thai learning app with an AI tutor
glot.it Learn Thai with AI — music, conversations, podcasts, 161 structured lessons, speech feedback & FSRS spaced repetition. Web PWA + iOS + Android (Capacitor).
あなたの施設に、おつくりできるもの
最初の30分のオンライン相談は無料です。料金は、内容をうかがってから決めます。
Booking and payment sites
Live availability, online payment (card, Square, PayPay), Japanese and English, and the confirmation mail.
AI chat and auto-replies
On your site, LINE or a tablet at the counter: answers from your own price list and rules, and hands the rest to a person.
Cameras and sensors on one screen
The same system as our site monitor, for your place. The terms of a pilot are being set now; ask us.
For campground and event operators
Booking-site emails into one booking table, the water-tank level, arrivals at the gate camera, and a daily sales report: the system that runs this place every day, for places run by very few people.
Advice for small places
For small inns, coworking spaces and campsites: the booking flow, ad measurement, listings and automating the daily work.
We also upgrade old PHP systems without switching them off(新しいタブで開きます)KENSAURUSのサイトへ(新しいタブで開きます)
取材・記事
この場所と、その仕組みについて書いたもの。
- 仕事とキャンプ…元牧場を理想郷に IT技術者・桜元さん(36) 2300万円投じ嬬恋に新拠点 集客苦戦も自然満喫の催しに活路無料の会員登録で読めます(新しいタブで開きます)
- 嬬恋牧場Work&Camp(新しいタブで開きます)
- 本物のラウンジを、ゲームの中で歩けるようにした:写真から描いたドット絵の室内(新しいタブで開きます)
- 受付のない入口に置いたタブレットの設計:全画面ウェブアプリと、触っていないときだけの更新(新しいタブで開きます)
- お金・安全・電気・水を一枚で見る「牧場モニター」の設計(新しいタブで開きます)
- A short update on the Ranch Monitor, the screen I use to run Tsumagoi Work&Camp with no front desk.(新しいタブで開きます)
- 入口のタブレットが、もうひとりの受付になった(新しいタブで開きます)
- There's no one at the front desk at Tsumagoi Work&Camp, so a tablet at the entrance does the greeting.(新しいタブで開きます)
- 山に来る前に、本物のラウンジをゲームで歩ける。ホームページをゲームにした話(新しいタブで開きます)
- You can walk around our lounge before you drive up the mountain.(新しいタブで開きます)
- 受付のいない山の牧場を、一枚の見取り図で回す:牧場モニター(新しいタブで開きます)
- Ranch Monitor: the control room for a mountain site with no front desk(新しいタブで開きます)
- 仕事のご相談|予約・決済・AIチャット・カメラの画面を作ります(新しいタブで開きます)
- Work with us: booking, payments, AI chat and camera dashboards(新しいタブで開きます)
- 仙人の管理室:ひとりで山の牧場を回すダッシュボード(新しいタブで開きます)
- There's no front desk at Tsumagoi Work&Camp.(新しいタブで開きます)
- このアプリたちを作っている人のこと(新しいタブで開きます)
- Who makes these apps, and why(新しいタブで開きます)
- 空き家だった牧場の建物を、働ける場所にするまで(新しいタブで開きます)
- 管理画面の中身を、もう少し:朝の画面・売店・Wi-Fi・カメラ・集客(新しいタブで開きます)
- 山のキャンプ場を、ひとつの管理画面で動かしている話(新しいタブで開きます)
- ESP32・カメラ・Wi-Fi・決済を、山のキャンプ場の管理画面ひとつにまとめた(新しいタブで開きます)
- 標高1,444mの元牧場で、光回線のラウンジとキャンプ場をやっています(新しいタブで開きます)
- Two months ago my wife and I opened a small campground and coworking space…(新しいタブで開きます)
よくある質問
- Who built the Tsumagoi Work&Camp system?
- Sennin Kenji (Kenji Sakuramoto, representative of Kensaurus LLC), who runs the place, designed, built and runs it alone: booking and payments, the AI chat, the kiosk at the door, the camera and sensor monitor, and the signs and print.
- Why did a software engineer start this place on a mountain?
- After his 20s and 30s in IT, Sennin Kenji wanted something completely different in his mid-30s: renovating a building, a mountain winter, hospitality and events. It was paid for by kensaurus's IT work and by money he lent the company from his own savings and salary. With no mains water or sewer, he is learning the septic tank, grass cutting and the rubbish one at a time. The place is also where kensaurus tries its consulting, development and photography work first.
- Can kensaurus build a booking site or a camera dashboard for my place?
- Yes. We build booking and payment sites, AI chat, and screens that put cameras and sensors on one plan for small inns, coworking spaces, campsites and similar places. The terms of a site-monitor pilot are being set now. Start by telling us about your place.
- How do I get in touch about a project?
- By email (kensaurus@gmail.com) or the form on this page; there is no phone. Tell us about the place, what you want to change and by when. The first 30-minute call (online) is free; a site visit is by arrangement, with travel costs charged.
- Can you connect my booking, accounting and expense apps so money is entered once?
- Yes. Tsumagoi Work&Camp writes accounting batches at each close and every night; Solo Boss pulls them every hour and books them as draft journal entries. Business costs paid personally go from the yen-yen money app as claims, and their status comes back. We build the same kind of link between your apps.
- Are you open to partners or investors?
- Yes. If you want to take this system to other places, help build places like this one, or are thinking about investing or partnering, we would like to hear from you.
仕事のご相談
メールで、施設のことと、変えたいことを教えてください。このページをどこで知ったかも、ひとこと添えてもらえると助かります。
最初の30分のオンライン相談は無料です。現地へうかがう場合は日程を相談して決め、交通費をいただきます。電話はありません。
フォームで相談する
この場所のこと:ホームInstagram(新しいタブで開きます)ご滞在・ラウンジのご質問はLINE(新しいタブで開きます)

Even up a mountain, you wire it one cable at a time. — Sennin Kenji







