@AT_Diary Sprint 2: Building a Privacy-First Diary on Apple Native Frameworks
Sprint 2 of @AT_Diary is complete with a successful build. Here’s what we shipped and how the architecture decisions are holding up.
The Core Premise
Most journaling apps ask you to trust their servers with your most personal data. AT_Diary doesn’t. Every piece of data it touches — your music history, your calendar events, your location context, your photos — is processed on-device and stored with iCloud encryption. Nothing phones home.
The Framework Stack
| Framework | Data Domain | Privacy Approach |
|---|---|---|
| MusicKit | What you’re listening to | Requests user permission; no data leaves device |
| EventKit | Calendar & reminders | Read-only access to authorized calendars |
| Contacts | Named entities in your day | Accessed by identifier only, never bulk imported |
| CoreLocation | Where you are | Significant location changes only, stored as geohash |
| Photos | Visual memory triggers | Thumbnails generated locally, originals never read |
Sprint 2 Deliverables
✅ MusicKit Integration
Authorization flow complete. The app captures the current track at entry creation time. Album artwork is pulled from the MusicKit catalog and displayed as a contextual thumbnail.
✅ EventKit Read Pipeline
Calendar events for the current day are fetched and ranked by duration and proximity to the current time. The top 3 events populate the “Today’s Context” section automatically.
✅ CoreData + CloudKit Persistence
All diary entries are stored in a CoreData stack with CloudKit sync enabled via NSPersistentCloudKitContainer. Your entries sync across all Apple devices without ever touching a third-party server.
✅ Successful Build
Clean build against iOS 18.0 target with zero warnings on all privacy-sensitive framework calls.
What’s Next: Sprint 3
- Entry card design: Rich contextual tiles with music, location, and event context
- Timeline view: Chronological scroll with ambient colors derived from album art
- On-device ML: Using
CreateMLto surface recurring patterns across your diary entries
@AT_Diary is a private project under Automated Technologies. No App Store release is planned at this time.