EU Digital COVID Certificate

https://ec.europa.eu/info/live-work-travel-eu/coronavirus-response/safe-covid-19-vaccines-europeans/covid-19-digital-green-certificates_en

The implementation of this application could have been done more efficiently and more securely with the SSI (Self-Sovereign Identity) technology, which is also based on open source, open standards, open governance, etc. Its technological foundations are being developed by the Linux Foundation. However it seems that no one knows or cares about it in the Free Software realm of the EU. This article explains more about this solution: