My vaccine card is a medical record and contains both PII and PHI. It worries me that I don't see a privacy policy. Of course as a developer I can check the source code, but it's probably best to include a policy.
This was inspired by an Andrew Yang tweet a few weeks ago. There has to be a better way to show people that we've been vaccinated without carrying around 5 inch piece of paper. Completely open source and easy to self host for maximum privacy.