Permanent contract change without hassle or paperwork

The startup WechselGott, with their app in the same name, wants to provide users full control over their contracts, insurance policies and payments. WechselGott takes charge of cancelling unneeded contracts as well as the management of ongoing contracts. The app helps users manage their finances with minimal effort, thanks to a modern and innovative interface.


Financial Services

Approx. 20 employees

Market activity
Throughout Germany

The challenge

Today, most consumers in Germany do not only juggle a large number of contracts for energy, mobile communications, etc., but also an increased number of saving accounts.

Thanks to automatic recognition of transactional data, it is possible to switch contracts paperless. The challenge was to develop a solution that not only takes the new PSD2 requirements into account, but also delivers a standardized and convenient user experience. WechselGott needed an Open Banking platform to achieve these goals.

“We are very pleased with the service and collaboration. The onboarding went smoothly, allowing lots of time to tailor an individual offer perfect for our needs. Throughout the project, professionals from agile coaching to CI/CD provided us with their expert advice. We also had the opportunity to participate in high-quality specialist events, to which a startup of our size would not have access.”

Werner Kräutlein, Managing Director, WechselGott

The solution

adorsys supported WechselGott in building the platform and all its components, including know-how transfer and provision of our professional services to ensure a fast time-to-market.

By integrating our Open Banking Gateway platform, adapted to WechselGott’s architectural requirements, we were able to set up an up-and-running end-to-end technology for our customer within an extremely short period of time.

We supported WechselGott in building and configuring all relevant components for the operation of a modular open banking platform, based on modern container technology.

In addition,  we set up an API management gateway to connect new partners via business APIs in the future. A state-of-the-art customer authentication process using Redhat Keycloak and the Secure Token Service provides B2B business with highest security.

We also facilitated the setup and configuration of the adorsys ModelBank to simulate PSD2 / HBCI compliant banks for querying transactions and triggering payments. The ModelBank is the perfect tool to subject the WechselGott application to required regression tests. It is also a mandatory requirement for all TTPs that want to integrate the B2B services of the WechselGott platform into their systems.

At last, adorsys’ UX experts supported WechselGott in upgrading and testing a new onboarding process for its users for smooth access into the WechselGott application.

and Setup

  • Deployment and implementation of Open Banking Gateway Platform & API Management Gateway, ModelBank as well as design onboarding process
  • Our team: 3 developers, 2 devops, 1 solution architect, 2 UX designers, 1 project lead
  • Technology stack: SpringBoot application with REST interface, HBCI, xs2a, FinTS, HBCI, Figma
  • Methodology: agile approach – Scrum, Sprints, Jira Boards, Miro


  • Delivering on the service promise of smooth and paperless contract switching
  • Implementation of all common TAN methods and existing SCA approaches
  • Extensive testability via the adorsys ModelBank
  • Seamless and consistent user experience across all users of the Wechselgott application