"Right after we started Zomeworks, Day Chahroudi came out from California. He’d read the Dome Cookbook and he came walking up the road one afternoon with a rucksack on his back. ...[W]hen he started telling me his ideas about how things worked—physics ...I was so impressed by his ...approach to engineering problems that I persuaded him to stay ...He did and ...soon he developed a solar tracker... very simple and easy to build."