sigil-caldav

A Sigil library for CalDAV calendaring (RFC 4791) and iCalendar parsing (RFC 5545). Works with Fastmail, Nextcloud, Radicale, and other CalDAV servers.

Features

• Server discovery -- principal URL and calendar home set via WebDAV
• Calendar operations -- list, find by name, create, delete
• Event CRUD -- create, read, update, delete calendar events
• Date range queries -- fetch events within a time window
• Recurrence expansion -- DAILY, WEEKLY, MONTHLY RRULE support with exception handling
• iCalendar parsing -- full VEVENT support including folded lines, attendees, timezones
• iCalendar generation -- create valid iCalendar text from event structs
• Timezone handling -- UTC and local timezone with DST-aware offset calculation
• Authentication -- HTTP Basic or Bearer token

Usage

Add sigil-caldav as a dependency in your package.sgl:

(from-git url: "codeberg:sigil/sigil-caldav" package: "sigil-caldav")

Then connect and manage calendars:

(import (sigil caldav))

(define client (caldav-connect
                 url: "https://caldav.fastmail.com"
                 username: "user@example.com"
                 password: (getenv "CALDAV_PASSWORD")))

;; List calendars
(define calendars (caldav-calendars client))

;; Get events in a date range
(define events (caldav-events client (car calendars)
                 start: "20260301T000000Z"
                 end: "20260401T000000Z"))

;; Create an event
(caldav-event-create! client (car calendars)
  (ical-event summary: "Meeting"
              dtstart: "20260315T100000Z"
              dtend: "20260315T110000Z"))

sigil deps install
sigil build
sigil test