Financial services-as-a-service — where entities like neobanks, retailers and others can create and sell their own financial products by way of a few lines of code and APIs — has been one of the bigger trends in the world of fintech in recent years, with embedded finance on its way to being a $7.2 trillion market by 2030, according to forecast from Bain Capital. Now, one of the companies building and providing those APIs is announcing some growth funding to expand. Railsbank, which builds APIs for banking, payment cards and…