Samuli (Sam) Zetterberg is a Finnish-born product designer and entrepreneur based in the San Francisco Bay Area.

He focuses on designing products that are built with care. He believes good design happens when intuition and precision meet, when something feels right and works better than expected.

At Circleback, he continues this pursuit and invests in early-stage teams who value clarity and craft. He was the first angel investor in Linear.app, drawn to its commitment to quality.

Outside of work, he spends most of his time with his two daughters and family in Marin.