Comfy Reminders for Calibre! 
A comfy Calibre plugin that provides a combined reminders and notebook system with notification alerts, rich export options (XLSX/CSV/RTF/ICS), filtering capabilities, batch actions, and automatic backups.
Features
Version 1.2 enhances the Comfy Reminders plugin for Calibre by introducing the ability to create reminders based on custom date columns in your library. This means you can now automatically set up reminders using dates from any date-type column in your book database, making it more flexible for tracking book-related dates and deadlines.
How to: click Settings to choose a custom date column. Then you can either:
- Right click the plugin toolbar button and select "Create reminders from selected books"
or
- Add the plugin to context menu for books in the library
Version 1.3: will add later
Installation
- Download the latest release zip file
- In Calibre, go to Preferences → Plugins → Load Plugin from File
- Select the downloaded zip file
- Restart Calibre
Basic Operation
- Type Reminder title
- Set time
- Click Add Reminder
(You can also use the Quick Reminder presets!)
Requirements
- Calibre 7.23 or later
- Works on Windows, macOS, and Linux (I've only tested on Windows, feedback is welcome)
Support
If you encounter any issues or have suggestions, check this MobileRead thread!
License
This plugin is licensed under the GNU GPL v3.