You might be interested in https://radicale.org/v3.html.
Runs on my odroid board with 26mb memory. The documentation is particularly good. I've used it as a replacement for the Synology CalDav and CardDav services.
It's very easy to install and does not require a DB. As a bonus, it stores everything as files which can be read and edited manually. It does require python.
It's very easy to install and does not require a DB. As a bonus, it stores everything as files which can be read and edited manually. It does require python.