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+# Requirements: Weekly ToDo List with Calendar Integration
+
+**Defined:** 2026-01-24
+**Core Value:** Provide users with a streamlined, unified view of their weekly tasks and calendar events that is faster and easier to use than traditional to-do list and calendar applications combined.
+
+## v1 Requirements
+
+### Core Functionality
+- [ ] **CORE-01**: User can view tasks and events in a weekly calendar view
+- [ ] **CORE-02**: User can add tasks to specific days within the weekly view
+- [ ] **CORE-03**: User can edit existing tasks (change title, date, description)
+- [ ] **CORE-04**: User can delete tasks from the weekly view
+- [ ] **CORE-05**: User can mark tasks as complete/incomplete
+- [ ] **CORE-06**: User can navigate between weeks using previous/next buttons
+- [ ] **CORE-07**: User can switch between day and week views
+- [ ] **CORE-08**: User can drag and drop tasks between days to reorganize them
+- [ ] **CORE-09**: User can persist tasks locally in the browser
+
+### Calendar Integration
+- [ ] **CAL-01**: User can connect their Google Calendar account to the application
+- [ ] **CAL-02**: User can connect their Apple Calendar account to the application
+- [ ] **CAL-03**: Connected calendar events appear alongside user tasks in the weekly view
+- [ ] **CAL-04**: User can view details of calendar events in the weekly view
+- [ ] **CAL-05**: User can filter to show/hide calendar events in the view
+
+### User Experience
+- [ ] **UX-01**: Application has a clean, minimalist interface similar to TeuxDeux
+- [ ] **UX-02**: Application is responsive and works well on desktop and tablet
+- [ ] **UX-03**: Tasks are visually distinct from calendar events
+- [ ] **UX-04**: Intuitive workflow for adding and editing tasks
+- [ ] **UX-05**: Clear visual indication of completed tasks
+
+## v2 Requirements
+
+### Advanced Task Management
+- [ ] **ADV-01**: User can create recurring tasks (daily, weekly, monthly)
+- [ ] **ADV-02**: User can assign categories/tags to tasks
+- [ ] **ADV-03**: User can set reminders for specific tasks
+- [ ] **ADV-04**: User can prioritize tasks (high, medium, low)
+- [ ] **ADV-05**: User can add descriptions and notes to tasks
+
+### Calendar Features
+- [ ] **CAL-06**: User can create new calendar events directly from the application
+- [ ] **CAL-07**: User can edit existing calendar events from the application
+- [ ] **CAL-08**: User can delete calendar events from the application
+- [ ] **CAL-09**: User can set reminders for calendar events
+
+### Data Management
+- [ ] **DATA-01**: User can export tasks to a CSV or JSON file
+- [ ] **DATA-02**: User can import tasks from a CSV or JSON file
+- [ ] **DATA-03**: User can backup their data manually
+- [ ] **DATA-04**: User can restore their data from a backup
+
+## Out of Scope
+
+| Feature | Reason |
+|---------|--------|
+| Multi-user collaboration | Focus on single-user experience for initial release |
+| Email notifications | Simplified for MVP, focus on in-app notifications |
+| Advanced reporting | Complex analytics beyond MVP scope |
+| Mobile application | Web-first approach for initial release |
+| Offline functionality | Requires complex sync mechanisms beyond MVP |
+| Rich text formatting | Text-only descriptions for simplicity |
+| Advanced filtering | Basic filtering by date and status for MVP |
+
+## Traceability
+
+| Requirement | Phase | Status |
+|-------------|-------|--------|
+| CORE-01 | Phase 1 | Pending |
+| CORE-02 | Phase 1 | Pending |
+| CORE-03 | Phase 1 | Pending |
+| CORE-04 | Phase 1 | Pending |
+| CORE-05 | Phase 1 | Pending |
+| CORE-06 | Phase 1 | Pending |
+| CORE-07 | Phase 1 | Pending |
+| CORE-08 | Phase 1 | Pending |
+| CORE-09 | Phase 1 | Pending |
+| CAL-01 | Phase 3 | Pending |
+| CAL-02 | Phase 3 | Pending |
+| CAL-03 | Phase 3 | Pending |
+| CAL-04 | Phase 3 | Pending |
+| CAL-05 | Phase 3 | Pending |
+| UX-01 | Phase 2 | Pending |
+| UX-02 | Phase 2 | Pending |
+| UX-03 | Phase 2 | Pending |
+| UX-04 | Phase 2 | Pending |
+| UX-05 | Phase 2 | Pending |
+| ADV-01 | Phase 2 | Pending |
+| ADV-02 | Phase 2 | Pending |
+| ADV-03 | Phase 2 | Pending |
+| ADV-04 | Phase 2 | Pending |
+| ADV-05 | Phase 2 | Pending |
+| CAL-06 | Phase 4 | Pending |
+| CAL-07 | Phase 4 | Pending |
+| CAL-08 | Phase 4 | Pending |
+| CAL-09 | Phase 4 | Pending |
+| DATA-01 | Phase 4 | Pending |
+| DATA-02 | Phase 4 | Pending |
+| DATA-03 | Phase 4 | Pending |
+| DATA-04 | Phase 4 | Pending |
+
+**Coverage:**
+- v1 requirements: 17 total
+- Mapped to phases: 17
+- Unmapped: 0 ✓
+
+---
+*Requirements defined: 2026-01-24*
+*Last updated: 2026-01-24 after initial definition*
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