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+> Mirrored from `/mnt/DATA/git/govoplan-calendar/README.md`.
+> Origin: `repository`.
+> Active tasks and changing state belong in Gitea issues; this wiki page is durable project context.
+
+---
+# govoplan-calendar
+
+GovOPlaN Calendar is the standalone calendar module. It provides tenant calendar collections, iCalendar/VEVENT event storage, a calendar WebUI, and integration boundaries for scheduling, tasks, mail, appointments, workflow, notifications, and external groupware.
+
+## Ownership
+
+This repository owns:
+
+- backend module manifest `calendar`
+- calendar permissions such as `calendar:calendar:read`, `calendar:event:read`, `calendar:event:write`, and `calendar:event:export`
+- tenant calendar collections
+- VEVENT storage with structured query fields plus raw iCalendar property preservation
+- iCalendar import/export endpoints
+- calendar WebUI package `@govoplan/calendar-webui`
+- `/calendar` route and navigation contribution
+
+Core owns auth, tenants, RBAC evaluation, database/session primitives, CSRF/API helpers, and shell layout.
+
+## Views
+
+The WebUI starts with the standard operational views:
+
+- month
+- week
+- workweek
+- day
+- continuous week-row calendar, where scrolling moves line by line through weeks rather than jumping from one month page to the next
+
+## iCalendar model
+
+The first backend implementation stores VEVENT data in two layers:
+
+- normalized fields for API range queries and calendar rendering
+- raw iCalendar property records and generated `text/calendar` output so unsupported VEVENT properties and parameters can round-trip
+
+This is intentionally not yet a network CalDAV server. CalDAV protocol sync, external ETags, REPORT handling, scheduling inbox/outbox behavior, and full recurrence expansion are calendar-owned follow-up work.
+
+## Development
+
+Install through the core environment:
+
+```bash
+cd /mnt/DATA/git/govoplan-core
+./.venv/bin/python -m pip install -r requirements-dev.txt
+```
+
+Run the WebUI from the core host:
+
+```bash
+cd /mnt/DATA/git/govoplan-core/webui
+PATH=/home/zemion/.nvm/versions/node/v22.22.3/bin:$PATH /home/zemion/.nvm/versions/node/v22.22.3/bin/npm run dev
+```
+
+## Module integration
+
+Backend entry point:
+
+```toml
+[project.entry-points."govoplan.modules"]
+calendar = "govoplan_calendar.backend.manifest:get_manifest"
+```
+
+Frontend package:
+
+```text
+@govoplan/calendar-webui
+```
+
+The integration concept is maintained in `docs/CALENDAR_INTEGRATION_CONCEPT.md`.