Taisei Dofuku

Born in 1997 and based in Tokyo. Working as an engineer since 2016. Previously worked at a creative agency, and now working independently. Handles the full scope of web production — from EC development and system architecture to infrastructure.

t.dofuku@monesynth.io

Tokyo, Kichijoji

Photography

2018

watatsumi

Client
watatsumi Inc.
Category
Business System
Role
Founder / Engineering, Interface Design, Business Operations

Brief

  • A business system for boating license schools, launched in 2018 and still used across multiple schools.
  • Automatically imports exam schedule and venue data, reducing duplicate entry and input errors across schools.
  • Built with a WAF and managed RDS backups so reservations and document issuance stay available.
01

PRODUCT

watatsumi is a business system built for boating license schools in Japan. It covers online reservations, vessel management, staff scheduling, automated generation of government-required documents including mark sheets, and the calculations that Japan’s multi-tier boating license system requires. Launched in 2018, it has been deployed across multiple schools and is still running in production today.

02

WORKFLOW

Japan’s boating license system has many combinations of license types, vessel tonnage, and navigation zones. Those rules determine which exams apply, which documents are required, and how fees are calculated. Much of this used to be handled by hand. Exam schedules and venue information were also entered separately by each school, which meant the same data was typed again and again.

watatsumi pulls exam schedules and venue data automatically from official sources. Schools no longer need to enter the same information repeatedly, which cuts down on daily work and input mistakes.

watatsumi data flow and operation flow diagram
From automatic import of exam schedule data to reservations and one-click document output
03

INTERFACE

The interface was designed for staff who use it every day, not for a one-time impression. Workflows were mapped so common tasks could be finished with fewer decisions and less switching between screens. Feedback from staff at schools using the system has been consistently positive.

It was built for schools that still relied heavily on paper and manual work, and it has been running in production for over seven years.

04

INFRASTRUCTURE

As the system behind reservations and document issuance for license schools, staying online and protecting data were the main requirements. The infrastructure was designed around stability, recovery, and room to grow.

The application runs in Docker containers on AWS, with deployments automated from GitHub via Capistrano. An AWS WAF sits in front to block malicious traffic, while the database runs on RDS with managed backups and recovery options. Because the system handles personal information and official documents, availability and security were part of the setup from the start. It has operated without major downtime since its 2018 launch.

watatsumi infrastructure diagram (WAF, EC2/Docker, RDS)
watatsumi infrastructure diagram (WAF, EC2/Docker, RDS)
Infrastructure focused on stable operation, with a WAF and managed RDS backups

Credits

  • Founder / Engineer — Taisei Dofuku