The serial entrepreneur, who had been an early pioneer in telecommunications technologies (like voice over internet protocols), saw the need for better connectivity between secondary services and financial institutions 19 years ago, just as new digital services around payroll processing, transit vouchers, store cards and other services were launching.

Now the company runs the backend integrations with financial institutions for some of the biggest names in financial technology and has just raised $77 million in financing from Accel Partners.

Not that Galileo necessarily needed the money. The company has been profitable for years since its bootstrapped beginnings and counts fintech giants like Chime Banking, Robinhood, Monzo and TransferWise among its customers. In fact, the debit and credit card service provider will process nearly $26 billion in financing by the end of the year, according to the company.

For financial services companies that are launching these days there are a few ways to get to market quickly. One is to partner with a financial institution that will handle the money for them in accounts that are FDIC assured; the other is to become a financial provider that’s fully regulated themselves.

Most companies have opted for the second route, and when they do, they need to find a way to hook into a bank’s financial system and the payment technologies that form the backbone of transaction processing through the debit and credit cards that a huge portion of the world relies on to buy things.

Accel partner John Locke, who is joining the Galileo board of directors, calls the company almost the flip side of the Braintree and Stripe investments that power transactions for most online merchants.

Rather than focus on the companies that are taking online orders and processing payments, Galileo deals with the consumers who are spending the money and powers the ways in which companies are trying to offer new services to get those consumers to switch from traditional banks to their upstart challengers (ironically still mostly powered by traditional banks).

“Through the API what they’re doing is creating and managing accounts, authorizing merchant transactions, monitoring fraud, initiating disputes and chargebacks, being able to configure products and a wide variety of product,” said Wilkes. “We support [direct deposit accounts] and we do credit products… all of these capabilities are capabilities that fit on our platform.”

Wilkes wouldn’t talk about the company’s valuation except to say that it’s worth “a substantial amount.”

What he will talk about is how Galileo will use the money it has raised. The Salt Lake City-based startup is planning to greatly expand its geographical reach beyond North America. It’s “actively pursuing opportunities in Brazil and Colombia and Argentina,” according to Wilkes. In fact, the company plans to open an office in Mexico City in the coming months to service new Latin American business.

Meanwhile, it already has something of a stranglehold on the market in the United Kingdom. “The top five largest fintechs in the U.K. are all clients today,” Wilkes said.

Unlike other companies in the market that take a fixed percentage of transactions, Galileo charges a variable amount of a few cents for every transaction that it processes to connect a startup with its banking back end.

“We’re in a golden era of fintech innovation and Galileo has quietly built the API infrastructure layer powering the industry’s most innovative products,” said Locke in a statement. “Clay and his team have built a very impressive business with many parallels to companies like Qualtrics and Atlassian: bootstrapping first to build a quiet, profitable powerhouse and now, ready to go big globally. We’re excited to help Clay and team take Galileo to the next level.”