Railsbank, a London-based open banking platform, has expanded into the U.S. market, landing San Francisco-based neobank Unifimoney as its first major customer.

Railsbank is offering a full range of products, including Banking as a Service, Cards as a Service and what it calls Credit Cards as a Service to both fintechs and "brand"customers.

"The high costs and complexity of launching credit card propositions have stifled innovation by creating barriers to entry to all but the largest of traditional financial companies," Nigel Verdon, co-founder and CEO of Railsbank, said in a company blogpost. "Fintech has changed the face of much of the banking industry, but to date the credit card market has been immune from this disruption."

He said that Railsbank's CCaS offering will drive change in the market by enabling a large volume of innovative fintech programs to reach the market quickly, but at a lower cost.

"We invested a year searching for the right partner: a company that could manage the complexity of credit cards and be a true innovation partner," Ben Soppit, CEO of Unifimoney, said in the blogpost.

Railsbank will run its U.S. operations out of Santa Monica, California, naming former Green Dot Corp. executive Dov Marmor as chief operating officer.