When William Hurley, the founder and CEO of online retirement startup Honest Dollar, sold his business to Goldman Sachs, it was just over one year old.

"As an entrepreneur, you have multiple goals. But one of the goals that people often don't speak about is that entrepreneurs usually want to change the world," Hurley tells Inc.

In particular, he's benefited from having access to the banking giant's data and talent. The 30-person company has grown by a third since the acquisition in March, and Hurley plans on hiring another 10 to 20 people in the coming months. Honest Dollar offers individual retirement accounts (IRA)s to small businesses and individuals, billed as an inexpensive alternative to 401(k)s. It uses software to generate portfolios of exchange-traded funds through Vanguard, and charges clients between $8 and $10 per employee.

The merger with Goldman Sachs has allowed Hurley to expand his product offering. Earlier this week, Honest Dollar announced a partnership with the Freelancers Union, a national advocacy group for independent workers. As part of the deal, the network of more than 300,000 freelancers and entrepreneurs can access the investing service at a discount. It takes around 90 seconds to open an account via Honest Dollar's app or website, the company says, which stays with the user no matter where they work. There is no minimum amount required to open an account.

Independent workers account for some 35 percent of the U.S. workforce, according to the "Freelancing in America 2016" report. Some 41 percent of freelancers say that saving up for retirement is their biggest concern -- yet they're still less likely to invest in retirement than full-time employees.

"Saving for retirement is a huge challenge for the 55 million Americans freelancing today, who have episodic and often unpredictable income," explained Sara Horowitz, the founder and executive director of the Freelancers Union, in a statement. "We are pleased to announce this partnership which helps to ensure that independent workers have affordable access to a user-friendly platform to help save for retirement."

Horowitz and Hurley first met at a round table discussion at the U.S. Department of Labor back in April, on retirement security and portable benefits. There, they realized there was "synergy" in terms of what they hoped to accomplish, Hurley explained.

In addition to giving freelancers access to the platform, Honest Dollar will begin creating educational content for those members. One common question that the company might answer, for instance, is whether one should opt for an SEP (simplified employee pension) IRA, where withdrawals are taxed as regular income, or a Roth IRA, where income tax is not paid on withdrawals.

Honest Dollar may have the cash and resources of Goldman Sachs behind it, but it's not the only company offering savings vehicles to small businesses and consumers. Betterment, for instance, is an automated investment manager (a.k.a. "robo-adviser") that last year launched a 401(k) service for businesses. Similar to Honest Dollar, Betterment claims that it can make investment services cheaper by using algorithms to serve clients, rather than human advisers.

As fintech startups continue to grow in popularity, banks like Goldman Sachs have taken interest. In 2015, asset manager BlackRock acquired FutureAdvisor, another robo-adviser, and Northwestern Mutual Life Co. bought LearnVest.

As an entrepreneur, Hurley doesn't characterize the transition to a larger behemoth as seamless -- especially given that his background was in technology, not in finance.

"As a 20-person startup, when you go into a company that has tens of thousands of employees who are all at the top of an industry -- there's a learning curve," he said. "I've learned more about finance in the last few months than I think most people might learn in years and years of their career. Goldman Sachs are not really in the business of buying startups, so this is a very new thing on both sides, but the teams have been very supportive of each other."