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 ## Libraries
 - **iCalendar Parsing:** [`ts-ics`](https://www.npmjs.com/package/ts-ics) (v2.4.0) - A library for parsing iCalendar data into structured JavaScript objects.
+- **Recurrence Expansion:** [`rrule`](https://www.npmjs.com/package/rrule) (v2.8.1) - A library for expanding recurring event rules (RRULE) into individual occurrences.
 
 ## Build & Development Tools
 - **Task Orchestration:** Deno Tasks (defined in `deno.json`) - Handles version synchronization and plug compilation.