The Diary ICS plugin synchronizes your Obsidian diary entries with system calendar applications like macOS Calendar or Windows Calendar by generating an ICS subscription link. It parses diary notes based on user-configured heading levels, creating calendar events with titles, descriptions, and deep links back to the original Obsidian files. Frontmatter fields can also be included as part of the event description using custom templates. A local HTTP server hosts the ICS file, enabling real-time updates and cross-device subscriptions within the same network.