9+ years of experience designing and coding B2B products from accounting software to developer tools.
[ Design Philosophy ]
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I design by understanding complex systems, shaping ideas with others, and learning from real use.
Before designing an interface, I learn the world around it—the user’s work, language, needs, and constraints. I begin with the bigger picture, then deepen my understanding through research and conversations with users and domain experts. This allows me to design from the real problem, not just the given requirements.
Design becomes stronger when it stops belonging to one person. I involve engineers, business partners, and users early, using rough ideas and prototypes as a shared language. By connecting different perspectives and areas of expertise, we shape the outcome and raise its quality together.
I start by giving intuition and curiosity a tangible form. Once an idea exists, I can test its assumptions, identify what feels wrong, and improve it through evidence and feedback. By shortening the distance between prototype, code, and real use, I balance speed, meaningful value, and attention to detail.
GMO Flatt SecurityTakumi is Japan’s first security AI agent capable of autonomously conducting vulnerability assessments. I led the UX and product design, navigating through a critical strategic pivot: transforming conversational agent into a high-trust agentic platform. By aligning technical constraints with user expectations, I helped evolve Takumi into a reliable partner for 60+ companies.
freeeFor many SMEs, employee mental health is a critical business risk, yet traditional "once-a-year" stress checks often identify issues too late. I led the rapid development of a new "Pulse Survey" feature for freee, transforming a compliance-focused tool into a proactive health management platform. By acting as both PM and Designer, I utilized domain modeling to align stakeholders and engineers, enabling a high-speed release cycle without sacrificing long-term technical integrity.
freeeThe launch of freee’s new product for tax accountants was a strategic move to evolve from a standalone accounting tool into a comprehensive business platform. I led the design process from discovering high-impact pain points through research to architecting a scalable information model. By balancing long-term technical value with pragmatic delivery, I ensured a high-quality release that streamlined complex tax firm operations.
GMO Flatt SecurityRedesigning the onboarding flow to make vulnerability assessment setup self-serve and transparent. Eliminated engineering support dependency and reduced time-to-value.
freeeRedesigning the accounting dashboard to make cash flow management more intuitive. Significantly increased user engagement and usage.
[ Side projects ]
I also build products as a weekend developer
