If Duncalfe skippered a turnaround, Collins' job is to reward its long-term investors (led by Boston-based OpenView and Josh Kopelman's First Round Capital and including Philadelphia's Robin Hood Ventures, among others) by scaling it up.

Brussin and the board are "obviously looking for the company to grow more rapidly than it has in recent years," he told me in a phone interview from France, where his youngest just completed high school, leaving her parents free to move home to the U.S. Collins, who briefly lived in North Wales as a child, said he and his wife, Robin, plan to live in Philadelphia, where he hopes to bike to work on the Schuylkill trails.

What does Monetate hope to offer its big retail customers that other retail-software providers don't? Customer preference data, its early product, "is now a commodity," Collins said. "What is harder, and what Monetate addresses, is helping you understand what your customers enjoy about their [online] experience. It could be as simple as the colors they prefer to see. It could be the products. It may be dynamic [individual] pricing, though we are not there yet." The goal: "a curated, focused, one-to-one experience, consistently, all the time, for every customer. That's what machine learning and artificial intelligence in online shopping is all about. Monetate's capabilities at present are consistent with that scenario."

Duncalfe's previous companies included Real Food Works, an organic food-delivery firm that secured backing from former Philadelphia Mayor Michael Nutter's StartupPHL Fund. Duncalfe said she merged that firm into Monetate, making the city a minor shareholder in the surviving company, with a small stake in Collins' success and Monetate's eventual IPO or sale at a profitable price.

Duncalfe, a Penn grad, was also a boss at Semprae Laboratories Inc., which hoped to develop a "female Viagra"; TurnTide, sold to Symantec in 2004; and Destiny Software, which set up early websites for her own former employer, SEI Investments, and other Philadelphia-area financial companies.