Lenda

A smarter iPhone calendar timeline.

What it does

iCal's week view wastes most of its space on empty hours and forces horizontal scrolling to see a whole day. Lenda inverts that:

• Day rows stacked vertically, each day rendered horizontally as a full 24-hour track.
• No horizontal scrolling. Every day fits edge-to-edge.
• Dynamic hour width. A time axis is computed from the union of every event in the loaded window. Hours where no day has events collapse to a thin tinted strip; busy hours expand to fill the rest. Time stays aligned across rows, so you can scan a column.
• Vertical scrolling in both directions. The view opens with today at the top; scroll up to revisit the recent past, down to look ahead. The loaded range expands lazily as you scroll past either edge.
• Month bar across the top. Tap any month to jump there; the bar highlights/centers the month of whichever day is currently at the top of the viewport.
• Today gets a single warm-orange accent — a thin bar in the day label, the day number, and a 1pt "now" line in the track. Everything else is neutral.

Look & feel

Dieter Rams territory: no cards, no shadows, no rounded chips, no gradients. Hairline rules separate sections. Events are pale tinted fills with a 2pt colored edge bar identifying the source calendar — colour is functional, not decorative. The compressed zones are simply a slightly darker surface — no hatching, no icons. The single warm accent (Braun-orange) is reserved for "today" and "now".

Architecture

Lenda/
  LendaApp.swift               @main, wires up CalendarStore + ContentView
  ContentView.swift            NavigationStack chrome
  CalendarTimelineView.swift   Top-level layout (month bar + axis + scroll list)
  MonthBar.swift               Horizontal month strip; tap to jump, auto-tracks visible day
  DayRowView.swift             One day; renders compressed zones, ticks, packed events, "now" line
  TimeAxisHeader.swift         Hour labels along the top, aligned with the tracks
  EventBlock.swift             One event rectangle
  PermissionView.swift         Calendar access onboarding

  CalendarSource.swift         protocol + plain SourceEvent struct (EventKit-free)
  EventKitCalendarSource.swift production implementation
  CalendarStore.swift          @MainActor ObservableObject; owns loaded days + TimeAxis
  DayBucket.swift              One day's projected events
  DayEvent.swift               SourceEvent projected onto a single day
  LanePacker.swift             Greedy lane assignment for overlapping events
  TimeAxis.swift               Piecewise-linear time-to-x mapping + AxisLayout helper
  Theme.swift                  Dieter Rams design tokens (DR namespace)

The CalendarSource protocol is the boundary that keeps EventKit out of the rest of the app — and lets LendaTests drive CalendarStore with a fake.

Tests

LendaTests covers the public interfaces of the logic layer:

• TimeAxisTests — boundary invariants (0 → 0, 1440 → totalWidth, monotonic), compression behavior across event densities, hour-tick ordering and uniqueness, determinism.
• LanePackerTests — non-overlap on each lane, minimum-lane assignment, lane reuse after a cluster ends, stable start-time ordering.
• CalendarStoreTests — access lifecycle (grant / deny / throw), bucketing by day, multi-day splits, all-day handling, time-axis derivation, lazy range expansion via ensureLoaded(around:), month-bar coverage.

Run with ⌘U in Xcode or xcodebuild test -scheme Lenda -destination 'platform=iOS Simulator,name=iPhone 15'.

Build & run

Requires Xcode 16+. Deployment target: iOS 17.

open Lenda.xcodeproj

Pick an iPhone simulator and ⌘R. Add a few events in the simulator's Calendar app first so there's something to render.