This 25-year-old data engineer is helping disrupt the world of finance

Robert Krzyzanowski is the kind of person who could choose to do many things with his life.

At 11, he scored in the 97th percentile in the math section of the SAT. At 16, Krzyzanowski, who speaks three languages fluently, was graduating from a special college-level program for gifted high school students at North Central in Naperville, Illinois.

By 23, he had a PhD in math from the University of Illinois at Chicago, and says he wanted to find a job where he had a real-world impact.

So Krzyzanowski, now 25, joined a little-known financial-technology start-up called Avant.

The Chicago-based online lending platform is one of a handful of startups that are looking to overturn the consumer loan market by finding ways to approve loans faster than banks. Avant can approve a loan the same day, for some people.

Founded in 2012, Avant is the the fastest-growing online marketplace lender, having raised more than $1.6 billion in three years. It's also a member of the unicorn club, with a valuation of more than $2 billion.

A couple of years ago, it might have seemed a risky place to start a career. Krzyzanowski's telling of his experience at Avant hits all the perks of working at a tech startup, starting with the drive of his co-workers.

The start-up 'drive'

"Even in grad school, where you have people that are from a wide variety of backgrounds and are generally motivated, I hadn't really seen the kind of drive that you do in the first few years of a really fast-growing venture," he said.

While his academic background is in math and statistics, at Avant he manages the programmers.

Krzyzanowski likes being able to wear many hats at Avant, another perk of being at a small operation. He's also able to see the direct impact of his work.

"Whenever we have customers streaming, the work that I do and the work that the people I work with do - it's constantly making decisions and at every second it's actually having an impact on our customers," Krzyzanowski said.

"So without that kind of tethering to the real world, it's hard to justify any work you're doing, and I found that to be true moving from academia into the industry."

What is data engineering?

Krzyzanowski's analytics team essentially transforms any insights that the company has on potential customers into useful data points that can be used to analyze their worthiness as a borrower.

"What we do boils down to making decisions - but making them better and making them faster," Krzyzanowski said.

Avant must be able to decide whether customers are fraudulent or not. (There are two kinds of fraud, Krzyzanowski explained: soft fraud - like someone who uses their current credit rating to get a one-time loan, knowing for example they may have some large debt coming in - and hard fraud, like identity theft.)

His team gauges that by using "offline" tools and machine-learning techniques to analyze hundreds or even thousands of variables to assess fraud risks. Most lenders are only able to analyze dozens of variables.

"Effectively what we're able to do is take these complicated algorithms and then translate them into code that can make the decision instantly," Krzyzanowski said.

They're able to do that because they've developed their own internal programming syntax and grammar.

"We really use best-in-class analytics and technology to provide a unique customer experience," Avant's CEO, Al Goldstein, told Business Insider.

Goldstein said that over 50% of Avant's customers get approved in real-time, while virtually all of them get funded the next business day.

"The result of that is really positive customer experience and customer satisfaction," he said.

This week Avant launched an auto finance product, and plans for a credit card product are in the works.

Goldstein wants to build out Avant's presence internationally, too, particularly in the UK and Canada.

Meanwhile, Krzyzanowski's analytics team has grown from 2 people to 30 and his position continues to grow with it.

"Coming in to work here I thought maybe I'll stay here long-term, maybe I'll stay a couple of months," Krzyzanowski said.

Two years later, it looks as though he may be in it for the long haul.