Hirohisa Tanaka

Joined as a Software Engineer Intern after being directly scouted by the CTO in October 2025.

Working across a broad range of areas, including web, mobile, and application security.

Responsibilities and experience include:

• Maintaining and improving an existing production codebase
• Refactoring and modifying legacy code
• Identifying and fixing multiple security vulnerabilities
• Developing and improving web application features
• Working across both frontend and backend systems
• Contributing to mobile application development
• Improving code maintainability while preserving existing behavior

Participated in a one-week frontend engineering internship in August 2026.

Developed the frontend of a CMS using React, TypeScript, TanStack Router, and Tailwind CSS.

Responsibilities and experience included:

• Implementing article, user, and administrator management screens
• Integrating the frontend with existing APIs
• Designing routing and data-loading flows with TanStack Router
• Implementing authentication-related frontend logic
• Building reusable UI components
• Implementing search, sorting, pagination, and view switching
• Writing tests for implemented features

Initially expected to work mainly on article-related pages, but completed the planned work ahead of schedule and expanded the implementation to additional areas of the CMS.

Worked as a Security Researcher with a focus on practical security education.

Responsibilities and experience included:

• Creating educational materials on SQL Injection
• Developing a sandbox environment for hands-on security training
• Designing exercises that allowed participants to safely learn common SQL Injection concepts
• Delivering a technical lecture and hands-on session
• Supporting participants during practical security exercises

Worked on an existing WordPress-based landing page as a freelance frontend engineer.

Responsibilities included:

• Modifying a custom WordPress theme
• Improving frontend performance and reducing page weight
• Implementing SEO improvements

Worked on the maintenance and infrastructure of existing landing pages.

Responsibilities included:

• Modifying three existing landing pages
• Migrating the web server environment from Apache to Nginx
• Configuring the new server environment and related infrastructure

Worked on website infrastructure migration and content recovery.

Responsibilities included:

• Migrating the company’s website to a new server environment
• Recovering lost website content after migration issues
• Restoring 5 pages
• Restoring 10 image assets

Worked continuously with the company for approximately one year as a freelance engineer and marketer.

Responsibilities included:

• Modifying and maintaining landing pages
• Supporting Google Ads campaigns
• Supporting Meta Ads campaigns
• Configuring and supporting LINE marketing tools
• Providing technical support for web-based marketing initiatives

Worked as a freelance RPA (Robotic Process Automation) engineer for an unlisted company, focusing on automating repetitive tasks and improving efficiency. Scope of work included:

• Developing and maintaining RPA scripts using Python and Java.
• Automating data entry and processing tasks
• Integrating RPA solutions with existing business processes