A onetime Goldman Sachs commodities analyst, Raj Mahajan returned to the investment banking giant in March 2015 to help lead one of Wall Street’s most influential trading executive teams. That’s by virtue of Goldman’s heritage as a market operations innovator and power broker and Mahajan’s nearly two decades as a technologist and company builder, most recently as CEO of high frequency shop Allston Trading. “The nature of buy-side trading is changing — it’s much more quantitative,” notes Mahajan, 43, Goldman’s global head of equities electronic execution services. “It’s unbundling, where execution and research split.” Guiding strategies relating to market structure and fast-growing products like exchange-traded funds, he explains that long-only asset managers are turning increasingly to automated trading while large hedge funds are kicking quantitative execution into higher gear. Goldman raised its game last fall with the acquisition of what Mahajan terms world-class algorithms from Sweden’s Pantor Engineering. Mahajan’s software standard: “Is it customizable, and can it survive the next shift in technology?” His return to Goldman reunited him with chief information officer R. Martin Chavez; they had served overlapping stints at the firm before co-founding commodities-trading-technology company Kiodex in 2000. SunGard Data Systems bought Kiodex in 2004, and Mahajan stayed on for eight years, rising to president of the global trading business. He holds a master’s degree in public administration from Princeton University and a BA in economics from the University of California, Berkeley.