Tobi Lütke is the founder and CEO of Shopify, a public company worth $17 billion. The shopping landscape is changing fast, with new tax laws, same-day delivery, in-store pickup and mobile payments adding new twists and capabilities all the time. Lutke, and Shopify, provide technology tools to simplify all that for merchants. 

I talked with Lütke recently at the Nasdaq Marketsite in Times Square, as talk of tariffs and taxes are swirling. We talked about what's allowed Shopify's stock to double in a year, and how he went from a teenage German apprentice to a Canadian entrepreneur … who's now a billionaire on paper, by the way.