Behind the App Part 3: The Builder



Our engineers, product managers, designers, and researchers are pushing boundaries to build next-level products for our members. From shaping the architecture of our mobile-first product suite to designing and building a holistic member experience, our team is at the center of it all. In this four-part series, we’re taking you behind the SoFi app to meet the dream team who is shaping the future of not only the company, but the entire fintech industry. 

Readers, if you haven’t read Parts 1 and 2 of this four-part series, stop what you’re doing and check them out.  Learn how Sarah’s work as a Staff Researcher is driving the strategy behind how we build and enhance our products. And how she partners with Product Managers, like Sasank, to determine the key areas our engineers and designers can focus on to better meet our members' needs.  Today, meet The Builder - Senior Staff Engineer, Donald Cestnik. He’s a SoFi veteran - has been with the company for more than six years and is sharing what products he helps to build and how his work translates to an awesome member experience. 

What product(s) do you support? 

Donald: My primary focus areas are fraud and risk. The goal is to identify potential fraudulent users and activity, while being as transparent to the member experience as possible. We offer a data gathering and risk decisioning service currently implemented in Personal Loans and Credit Card. This service allows those product teams to focus on the member experience while we focus on fraud and loss prevention.  In the future we hope to extend that product to have a wider reach across all products and reduce effort by our member-facing product teams. 

Can you share how your work as an engineer translates to the member’s experience? 

Donald: Accurately identifying fraud and providing risk scoring keeps our costs down and boosts trust. (Heard this before, readers? This was a transformational idea Sarah uncovered in her work - go check it out).

Our impact is that members will have an assurance that they will not be impacted by fraudsters. Members should feel safe with SoFi. In addition, when we limit fraud, those funds that would’ve been lost can be directed toward offering more competitive products to our members, providing better rates and a user experience beyond our competitors.

What attracted you to work at SoFi and why do you stay?

Donald: I started at SoFi over six years ago. SoFi gave me the opportunity to work on large, complex and interesting problems, while being located in Montana where I can enjoy the outdoors and blue collar atmosphere. Early on, it was exciting to be exposed to a very broad array of business areas, primarily doing greenfield development. Since then, work at SoFi has stayed fresh due to new challenges of scale, compliance, and ensuring our newfound name recognition is positive. Ultimately, I enjoy being an engineer at SoFi, because I feel my work is valued here and I have the ability and freedom to be creative and have an impact.

“SoFi gives me the opportunity to work on large, complex and interesting problems.” 

Very important, we have to know - if you could have any super hero power, what would it be and why? 

Donald: It would certainly end up being a curse, but precognition would be a good one. By being able to see or sense the future it would be possible to change actions now that would shape and alter it. Through precognition, every situation encountered could be handled to have the best possible outcome.

Thanks for sharing your perspective, Donald - and for helping to keep our members’ data safe. Up next - the finale of our four-part series, meet The Designer who is putting it all together.


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The individual featured is a SoFi employee. Their personal experiences, obviously, do not take into account your own specific objectives, financial situation, and needs. Results will vary.

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Kari Scheidt, Talent Brand @ SoFi