Founder / Creative Director

Toshiyasu Sayama began his career as a product designer, working across consumer electronics, automotive aftermarket products, furniture, daily goods, and healthcare products.

He later spent more than 20 years in automotive interior design and development, working on instrument panels, center consoles, door trims, air vents, and advanced interior concepts. His experience spans both design development and production, including international assignments in North America and China.

Through these experiences, he has worked across different markets, cultures, and manufacturing environments, developing products from early concepts through to production.

In 2026, he founded Walltosh in Nagoya, Japan.
Walltosh supports companies and development teams from the early stages of an idea through product planning, design, 3D modeling, prototyping, and realization.