At Visa, MacIlwaine was responsible for developing new products and services across the card scheme's commercial and consumer product divisions.

In his role, MacIlwaine has been charged with orchestrating the design and implementation of Green Dot's overall technology strategy.

Will Sowell, chief operating officer at Green Dot, says: "John's particular expertise in developing secure enterprise level mobile and web-based payment platforms and transaction processing systems will ensure Green Dot's voracious appetite for new technology is well satisfied into the future."

His appointment comes just two weeks after Green Dot was given the all-clear by regulators to buy Bonneville, a small Utah-based bank. The pre-paid card company plans to rename Bonneville as Green Dot Bank and use it to issue its own cards linked to FDIC-insured accounts and provide settlement services.