I run Nextcloud for this. Never understood the complaints about it, I find it hard to believe everyone’s so short of CPU power that Nextcloud is anything more than a rounding error running in the background.
There’s half a dozen of us using it for shared calendars, files, and contacts.
Currently around 6TB of files, a couple of hundred or so contacts in the shared contacts list, and many recurring (and one off) events.
Been working perfectly since before Nextcloud forked from OwnCloud.
It’s like rain on OPs wedding day