Radicale VS Baïkal

Maybe https://radicale.org/ could fit the bill, CalDav for as a calendar server and CardDav for contacts. - Source: Hacker News / 8 months ago

I now use CalDAV Synchronizer to sync Outlook to my Radicale CalDAV / CardDAV "server" (a Raspberry Pi), with DAVx running on our phones. Source: 11 months ago

Setup: 1. Install a CalDev server on my home server (running Debian Linux) using maybe Radicale (https://radicale.org/) 2. Use the Linux version of ProtonMail Bridge on this server to set up IMAP to connect to this CalDev server 3. Configure filters to automatically forward event invites sent to my ProtonMail address to my CalDev server, decrypted by Bridge 4. Configure my CalDev server to use ProtonMail to send... Source: about 1 year ago

Caldav is what you are looking for. The other comments mention implementations of them and I can vouch for radicale pretty barebones but does its job. Source: about 1 year ago

We are thinking of writing a guide to setting up a small Radicale instance. This could be hosted on a raspberry pi, or small NAS or something. Source: about 1 year ago

I'm sure there are many ways, but I used https://sabre.io/baikal/ to get a CalDAV and CardDAV server on cheap (shared, bog standard) web hosting, and then pointed Thunderbird to it. Apart from automatic syncing of contacts between devices, I can now edit my phone contacts on the desktop, which is so awesome. - Source: Hacker News / 5 months ago

I use Baikal. It's a CalDav and CardDav server which run easily on a NAS with Docker for example. Source: 9 months ago

You might want to look into https://sabre.io/baikal/ or get a true groupware mailbox, e.g. An Exchange account with M365. Source: 10 months ago

I'm using Baïkal to manage my contacts, events and tasks and I'm pretty happy with it. Source: 11 months ago

Also look at Baikal, in addtion to Radicale. Source: 11 months ago