Ryotaro Isoyama
Tokyo,13
Summary
I am a software engineer with extensive experience in developing and maintaining large-scale mobile applications. At Gurunavi, I contributed to the restaurant search and reservation app used by millions, and successfully led a major project to rebuild the iOS/Android app with Flutter, significantly improving performance and maintainability.
After co-founding and working at a startup, I transitioned to working as a freelance engineer. Currently, I am the sole mobile engineer for a subscription-based craft beer delivery service, responsible for the full lifecycle of the app—from proposal and design to implementation, release, and maintenance—using Flutter for both iOS and Android.
I enjoy building applications independently and take pride in delivering high-quality, scalable solutions with technologies like Firebase, CI/CD, and analytics tools to support product and business goals.
After co-founding and working at a startup, I transitioned to working as a freelance engineer. Currently, I am the sole mobile engineer for a subscription-based craft beer delivery service, responsible for the full lifecycle of the app—from proposal and design to implementation, release, and maintenance—using Flutter for both iOS and Android.
I enjoy building applications independently and take pride in delivering high-quality, scalable solutions with technologies like Firebase, CI/CD, and analytics tools to support product and business goals.
Overview
4
4
years of professional experience
Work History
Lead Mobile Engineer (Flutter, IOS/Android)
Freelance / Subscription-based Craft Beer Delivery Startup
01.2025 - Current
- Independently designed, developed, and maintained a cross-platform mobile application (Flutter) for iOS and Android, serving a monthly active user base of ~1,400.
- Led end-to-end feature development including planning, requirements gathering, implementation, testing, and release.
- Proposed and implemented new product features based on user feedback and business needs, contributing to customer engagement and retention.
- Handled app store operations (App Store & Google Play), CI/CD pipelines, and crash/error monitoring setup.
- Collaborated directly with stakeholders to align technical priorities with business objectives.
co-founder & CTO
Ten-Days, Inc.
10.2024 - 02.2025
- Responsible for technology stack selection and feasibility assessment of implementations.
- Collaborating on specification adjustments and application design.
- Leading end-to-end app development, including implementation, testing, and deployment.
- Defining operational strategies and ensuring smooth app management.
- Actively contributing to business growth through sales initiatives and process development.
Mobile Application Engineer
Freelance Software Engineer (Multiple Clients)
04.2024 - Current
- Developed mobile applications for various industries.
- Collaborated with teams to design and implement scalable solutions.
Mobile Application Engineer(iOS)
Gurunavi, Inc.
04.2021 - 04.2024
- Developed and maintained a large-scale restaurant search and reservation app used by millions of users.
- Directed contract engineers by providing clear instructions and technical guidance.
- Mentored new graduates through OJT (On-the-Job Training), fostering their growth as engineers.
- Designed replacement architectures for legacy systems, ensuring scalability and maintainability.
- Contributed to the successful migration of the app to Flutter, enhancing performance and user experience.
Education
Bachelor - Electrical and Electronic Engineering
Kyoto University
Kyoto01.2019
Skills
- Project Management
- Teamwork
- Leadership
- Effective Communication
- Critical Thinking
- Dart
- Mobile Application Engineering
- GCP/Firebase
LANGUAGES
Japanese(Fluent)
English (Basic)
Timeline
Lead Mobile Engineer (Flutter, IOS/Android)
Freelance / Subscription-based Craft Beer Delivery Startup
01.2025 - Current
co-founder & CTO
Ten-Days, Inc.
10.2024 - 02.2025
Mobile Application Engineer
Freelance Software Engineer (Multiple Clients)
04.2024 - Current
Mobile Application Engineer(iOS)
Gurunavi, Inc.
04.2021 - 04.2024
Bachelor - Electrical and Electronic Engineering
Kyoto University
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