PSD2 Open Banking APIs: What Engineering Teams Must Know

PSD2 mandates banks provide API access for account info and payment initiation, with three functional categories: AISP, PISP, and CBPII. Strong Customer Authentication (SCA) requires two-factor authentication, often via redirect flows, which is the most underestimated engineering challenge. Compliance involves building or consuming APIs under strict regulatory standards like Berlin Group's NextGenPSD2.