5n7.me Tokyo · UTC+09:00 · ja / en ·
Payment platform. AI-native teams. Small businesses.
Engineering Manager · Software Engineer · Photographer · Corgi Lover
Now
Merpay / EM + IC
2 teams · 10 engineers
Side
Yomoyama / CTO
Real estate pricing
Side
RINGBELL / Sr. SWE
Marriage agency platform
Based
Tokyo, JP
UTC+09:00 · ja/en
I build the payment platform behind Mercari's marketplace as an Engineering Manager at Merpay, leading two payment-core teams while still shipping code. On the side I run engineering at Yomoyama (real-estate price estimation) and RINGBELL (a marriage agency service). Trained in image processing (MSc, Tokyo University of Science); off the clock I photograph Tokyo and follow a corgi around it.
Go / Observability / FinTech / Payment Systems / Real Estate / Stocks
Engineering Manager for two teams in Merpay — Payment Core (since Mar 2025) and Payment Solution (since Jan 2026) — leading 10 engineers in total. Also contributing as an individual contributor on the PCP Foundation team since Mar 2026.
Main developer and architect of a marriage agency service in Japan.
Leading full-stack development of a real estate price estimation service.
Developed a real estate price estimation service.
Led technical development of Payment Platform in the Payment Core team.
Joined as a new graduate and worked on developing Payment Platform used company-wide.
Focused on artificial intelligence and machine learning. Conducted research on image processing under Professor Yukinobu Taniguchi.
Coursework in information engineering and statistics. Conducted research on image processing under Professor Yukinobu Taniguchi.