A real-time API cut bank onboarding from 3 months to 1

How it happened

1. 2021 — Where it started

   Onboarding was known to be slow, but nobody had located the cost. I ran the existing process myself, as a partner would, and found it. The file structure was complex, and every onboarding ran differently. A partner got no feedback until a batch failed — weeks in.

2. The architecture decision

   Replace the batch file with a real-time Beneficiary Management API. I defined the core use cases and specified the OpenAPI/Swagger contract, so the interface was agreed before code. Every partner-facing API then moved behind one Apigee gateway — a single front door for security, monitoring, and versioning.

3. First release — with N26

   The first version went to N26 before anyone else; their feedback shaped the next one. Real-time validation moved the error to the moment it was made, so integration became a conversation instead of a wait.

4. The standard path

   Once it held, I validated the API as the standard path, not an option alongside the CSV upload. One documented route, written developer-first. Self-service is the change management — it lowered integration cost and improved developer experience.

   

5. Today

   66%

   shorter bank onboarding

   Real-time APIs replacing batch processing

   28

   markets integrated

   Travel and appliance protection products

   €26M

   gross written premium integrated

   Across 28 onboarding markets