Background and objectives: Most telemedicine solutions are proprietary and disease specific which cause a heterogeneous and silo-oriented system landscape with limited interoperability. Solving the interoperability problem would require a strong focus on data integration and standardization in telemedicine infrastructures. Our objective was to suggest a future-proof architecture, that consisted of small loose-coupled modules to allow flexible integration with new and existing services, and the use of international standards to allow high re-usability of modules, and interoperability in the health IT landscape. Methods: We identified core features of our future-proof architecture as the following (1) To provide extended functionality the system should be designed as a core with modules. Database handling and implementation of security protocols are modules, to improve flexibility compared to other frameworks. (2) To ensure loosely coupled modules the system should implement an inversion of control mechanism. (3) A focus on ease of implementation requires the system should use HL7 FHIR (Fast Interoperable Health Resources) as the primary standard because it is based on web-technologies. Results: We evaluated the feasibility of our architecture by developing an open source implementation of the system called ORDS. ORDS is written in TypeScript, and makes use of the Express Framework and HL7 FHIR DSTU2. The code is distributed on GitHub. All modules have been tested unit wise, but end-to-end testing awaits our first clinical example implementations. Conclusions: Our study showed that highly adaptable and yet interoperable core frameworks for telemedicine can be designed and implemented. Future work includes implementation of a clinical use case and evaluation.