# Glossary

**📝 SANITY CHECK IMPROVEMENTS APPLIED:** This document has been updated to accurately reflect current implementation status vs. planned features.

**T (slot time)** — The local wall-clock time a notification should fire (e.g., 08:00). *See Notification System → Scheduling & T–lead.*

**T–lead** — The moment **`prefetchLeadMinutes`** before **T** when the system *attempts* a **single** background prefetch. T–lead **controls prefetch attempts, not arming**; locals are pre-armed earlier to guarantee closed-app delivery. *See Notification System → Scheduling & T–lead and Roadmap Phase 2.1.*

**Lead window** — The interval from **T–lead** up to **T** during which we **try once** to refresh content. It does **not** control arming; we pre-arm earlier. *See Notification System → Scheduling & T–lead.*

**Rolling window** — Always keep **today's remaining** (and tomorrow if iOS pending caps allow) locals **armed** so the OS can deliver while the app is closed. *See Notification System → Scheduling & T–lead and Roadmap Phase 1.3.*

**TTL (time-to-live)** — Maximum allowed payload age **at fire time**. If `T − fetchedAt > ttlSeconds`, we **skip** arming for that T. *See Notification System → Policies and Roadmap Phase 1.2.*

**Shared DB (planned)** — The app and plugin will open the **same SQLite file**; the app owns schema/migrations, the plugin performs short writes with WAL. *Currently using SharedPreferences/UserDefaults.* *See Notification System → Storage and Roadmap Phase 1.1.*

**WAL (Write-Ahead Logging)** — SQLite journaling mode that permits concurrent reads during writes; recommended for foreground-read + background-write. *See Notification System → Storage and Roadmap Phase 1.1.*

**`PRAGMA user_version`** — An integer the app increments on each migration; the plugin **checks** (does not migrate) to ensure compatibility. *See Notification System → Storage and Roadmap Phase 1.1.*

**Exact alarm (Android)** — Minute-precise alarm via `AlarmManager.setExactAndAllowWhileIdle`, subject to policy and permission. *See Notification System → Policies and Roadmap Phase 2.2.*

**Windowed alarm (Android)** — Batched/inexact alarm via `setWindow(start,len)`; we target **±10 minutes** when exact alarms are unavailable. *See Notification System → Policies and Roadmap Phase 2.2.*

**Delivery-time mutation (iOS)** — Not available for **local** notifications. Notification Service Extensions mutate **remote** pushes only; locals must be rendered before scheduling. *See Notification System → Policies.*

**Start-on-Login** — Electron feature that automatically launches the application when the user logs into their system, enabling background notification scheduling and delivery after system reboot. *See Roadmap Phase 2.3.*

**Tiered Storage (current)** — Current implementation uses SharedPreferences (Android) / UserDefaults (iOS) for quick access, in-memory cache for structured data, and file system for large assets. *See Notification System → Storage and Roadmap Phase 1.1.*

**No delivery-time network:** Local notifications display **pre-rendered content only**; never fetch at delivery. *See Notification System → Policies.*