Real World Interoperability in EV Charging: The Tooling Stack Behind the EVerest Ecosystem
Event Recap: FOSDEM 2026
TL;DR
At FOSDEM 2026, Marco Möller presented how the EVerest open source project approaches interoperability challenges in EV charging through shared software implementations, system-level testing, virtual testing environments, and operational feedback loops. The session explored how EVerest combines protocol implementations, hardware-in-the-loop testing, interoperability events, and federated testing to support increasingly complex EV charging ecosystems.
The Scale of the Interoperability Challenge
Möller described EV charging as a rapidly expanding ecosystem involving vehicles, charging stations, backend systems, displays, and grid-related infrastructure.
Using an example of 1,000 vehicle types, 1,000 charging station types, and 1,000 backend systems, he noted that this creates roughly a billion possible interoperability combinations.
According to Möller, this complexity contributes to maintenance issues, stranded assets, and software quality problems across deployments.
He argued that “just adding more and more standards is not the solution,” and instead described EVerest as an effort to provide a shared open source software stack capable of supporting many charging configurations.
What EVerest Provides
EVerest is an Apache-licensed open source software stack under LF Energy.
Möller explained that the project supports interactions between charging stations, electric vehicles, backend systems, payment terminals, displays, and power grid systems. Because charging infrastructure varies significantly between residential chargers, public stations, and large charging parks, EVerest uses a modular framework approach that can be adapted to different hardware setups.
The project also implements multiple sides of communication protocols. For example, EVerest may implement both charger-side and vehicle-side components, allowing systems to be tested before interacting with third-party implementations.
Beyond Unit Testing
A major focus of the presentation was the need for broader interoperability testing beyond traditional unit tests.
Möller explained that EVerest combines standard software engineering practices such as CI/CD pipelines, code reviews, static analysis, and audits with additional testing approaches including:
- Hardware-in-the-loop testing
- Cross-testing against third-party systems
- Monitoring deployed systems
- Operational feedback from real deployments
The session also highlighted collaboration with the Open Charge Alliance (OCA), the organization behind OCPP. According to Möller, EVerest releases are tested against OCA tooling, while OCA releases are also validated against EVerest implementations in what he described as a “golden system under test” approach.
Virtual Charger Parks and Federated Testing
Möller also demonstrated a “virtual charger park” environment built around EVerest.
Using Docker deployments and Node-RED interfaces, the system can emulate charging infrastructure in cloud environments while still running the same underlying communication logic used in production systems.
The presentation additionally covered a federated testing approach that allows vendors to run shared community test cases within their own commercial environments. In this model, central systems trigger tests against new code branches, vendors execute those tests locally, and results are shared back with the ecosystem.
According to Möller, this helps distribute testing effort across organizations using the software stack.
Operational Feedback and Standards Development
The session emphasized that interoperability work continues after deployment.
Möller discussed monitoring deployed infrastructure, gradually rolling out firmware updates, and feeding operational findings back into development workflows. He also referenced penetration testing work sponsored by LF Energy and conducted by Quarkslab.
The presentation additionally explored the relationship between open source implementations and standards development. Möller noted that adoption cycles for EV charging standards can be slow, while implementation work often reveals ambiguities or interoperability gaps that may not appear in specifications alone.
According to the session, open source implementations can help expose these issues earlier through broader testing and deployment experience.
AI Disclosure
This post used artificial intelligence tools for research, structural assistance, or grammatical refinement. The final content was reviewed, edited, and validated by human contributors to LF Energy to ensure accuracy and alignment with our community standards. We remain committed to transparency in the use of generative technologies within the open source ecosystem.
