A product designer with experience in fintech and e-commerce. Currently based in Tokyo, working in PayPay, a leading fintech company in Japan.

Case Study

Case Study

Top up experience redesign

Optimized through A/B testing, boosting top-up amounts by 7% and increasing GMV by 5%

Fintech

App

2024

Coming Soon

Top up experience redesign

Optimized through A/B testing, boosting top-up amounts by 7% and increasing GMV by 5%

Fintech

App

2024

Coming Soon

Top up experience redesign

Optimized through A/B testing, boosting top-up amounts by 7% and increasing GMV by 5%

Fintech

App

2024

Coming Soon

Credit Card Vouchers

Addressed diverse user financial needs and introducing a new payment method

Fintech

App

2024

Coming Soon

Credit Card Vouchers

Addressed diverse user financial needs and introducing a new payment method

Fintech

App

2024

Coming Soon

Credit Card Vouchers

Addressed diverse user financial needs and introducing a new payment method

Fintech

App

2024

Coming Soon

From People I've Worked With

From People I've Worked With

Kazuya

Associate Design Director @AKQA/ Ex-PayPay

Associate Design Director @AKQA/ Ex-PayPay

Yu was a key team member during my time at PayPay, consistently delivering high-quality designs on time while managing multiple projects. He effectively prioritized tasks, kept the team updated, and adapted his communication to different stakeholders, ensuring smooth project progress. Beyond his design work, he contributed to our Design Ops group, optimizing the Design QA process and establishing accessibility checkpoints, which improved team efficiency and design usability.


Yu’s professionalism, attention to detail, and proactive approach make him an invaluable team member who elevates the quality of both design and collaboration.



Simon Lin

Simon Lin

Principal Product Designer @Canva

Principal Product Designer @Canva

Yu is my team member at AAPD. He started as a teaching assistant for online courses and has grown into an instructor in the product design bootcamp. Over time, he’s gone from following instructions to independently leading projects, showing impressive learning skills, attention to detail, and great communication.


Yu’s especially good at working with stakeholders, keeping things on track while creating a positive and efficient vibe. Working with him is always a pleasure—he’s someone you can count on.

Keith Oh

Keith Oh

Head of Product Design @Carousell

Yu was a valued member of my team who successfully managed several challenging projects independently during his time with us. These projects were particularly demanding due to initially unclear requirements, but he conducted thorough research to bring clarity to the design briefs. He approached challenges with patience and a methodical mindset, analyzing issues effectively and proposing well-thought-out solutions.


Yu’s communication skills were exceptional; he consistently collaborated with team members, including engineers, to understand diverse perspectives, ensure smooth project progress, and cultivate a positive, collaborative environment. His professionalism and strong sense of responsibility made him a dependable and trustworthy team member.

Tom Lee

Tom Lee

QA Engineer Manager @PayPay

QA Engineer Manager @PayPay

Yu is a product designer I worked with at PayPay on several QA projects. He demonstrated professionalism and attention to detail, from pixel-perfect checks to evaluating the overall process. When discrepancies between design and development arose, he calmly assessed the situation and worked with the team to find practical solutions, ensuring the final product maintained quality and consistency.


Additionally, Yu actively contributed by suggesting bug fixes and optimizations, improving both the product and team efficiency. His focus on detail and commitment to quality make him a highly reliable team member. I’m confident his contributions will always elevate the design outcome.

Belissa

Belissa

Senior Product Designer @Carousell

Senior Product Designer @Carousell

Yu was a former colleague at Carousell, and I was always impressed by his design approach. He balanced user experience with business goals, ensuring thoughtful, practical solutions even when compromises were needed. His designs seamlessly met both user and product needs.


Yu’s collaborative spirit stood out—he often suggested pair design sessions, which helped prevent miscommunication and made problem-solving enjoyable. His dedication to growth was inspiring; he actively sought feedback in design reviews and consistently improved his work based on it. His openness, creativity, and positive energy made him an invaluable teammate.

ryanchyy@gmail.com

Copy

Copyright © 2025 by Chang Yu.

Made with love and Four Season Teas (30% sugar, less ice)

ryanchyy@gmail.com

Copy

Copyright © 2025 by Chang Yu.

Made with love and Four Season Teas (30% sugar, less ice)

ryanchyy@gmail.com

Copy

Copyright © 2025 by Chang Yu.

Made with love and Four Season Teas (30% sugar, less ice)

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