This morning Alpaca, a startup that helps other companies add commission-free equities trading to their own products, announced a $10 million Series A. The new capital event was led by Portag3, and included prior investors Social Leverage, Spark Capital, Fathom Capital and Abstract Ventures. The company previously raised a $6 million pre-Seed and $6 million Seed round that TechCrunch covered last November. Alpaca is a company that has cropped up in our coverage of the startup and private capital markets recently, adding its perspective to our discussion of API-powered startups and their recent success. By our math, the new round pushes Alpaca to around $22 million in total funding. It’s done a lot with the pre-existing funds, including driving its transaction volume sharply higher over the last year.