If you've tried to build anything with European bank APIs, you probably hit the same wall I did: the certificate requirement. PSD2 says you need an eIDAS QWAC certificate to talk to banks directly, and those aren't cheap or quick to obtain.
But there's a path that skips the certificate entirely. I'll show you how it works — with real code you can run today.
The short version
Instead of obtaining your own eIDAS certificate and registering as a Third Party Provider with every bank, you use an Account Information Service Provider (AISP) that already has the certificate. Your app talks to their API; they talk to the banks. You never touch a certificate.
The trade-off: you depend on an intermediary. But for most indie projects, small businesses, and personal-finance tools, that's a perfectly reasonable trade. You get bank data via a clean REST API instead of fighting with mutual TLS and per-bank registration.
