Organizer: Gaia-X and Gaia-X Hub Greece
Date: 28-29/05/2026
Place: Athens, Greece
Link: https://gaia-x.eu/gaia-x-sets-practical-interoperability-in-motion-during-its-tech-x-athens-edition/
Giving a talk with the title “Myrtus Project: A SHACL-based remote Danube extension”
On 28–29 May 2026, MYRTUS took part in Gaia-X Tech-X & Hackathon #9 in Athens, organised with Gaia-X Hub Greece. Giulia Biagioni (TNO) presented “Myrtus Project: A SHACL-based remote Danube extension”, the work done with her colleagues Coen van Leeuwen and Bart Driessen to integrate MYRTUS with Danube, the extensible compliance framework of Gaia-X.
When a new organisation wants to join the MYRTUS ecosystem, a compliance service, designed to support the MIRTO cognitive engine, checks its Gaia-X Verifiable Presentation against MYRTUS rules written in SHACL. The rules check that the organisation has a valid registration number and LEI code, is based in the European Union and has accepted the Gaia-X terms and conditions.
At first, MYRTUS developed and maintained its own engine to process the credentials and run the SHACL validation. After learning about Danube at the Gaia-X Summit 2025 in Porto, the team moved the whole verification to Danube. MYRTUS now only publishes its SHACL rules at a web address: Danube verifies the credentials, validates them against those rules and returns a compliance report as a Verifiable Credential signed with the MYRTUS decentralised identifier.
A demonstration showed the three steps: the partner presents its credentials as a signed token, Danube verifies the signature and authenticity, and the decoded credentials are checked against the MYRTUS rules. A test organisation established in the Netherlands passed all checks; when its country was changed to one outside the EU, the validation failed as expected. Submitting the full token to the Gaia-X compliance dispatcher ran all the checks at once and returned a signed compliance report.
Delegating the checks to Danube means there is no compliance engine to maintain, only the rules. It also brings MYRTUS fully in line with the Gaia-X compliance framework, improving interoperability across ecosystems and allowing the MYRTUS rules to be reused by others. The team thanked the Danube team for their support.
