Unit Dependencies: Shoe Choo

Dependency Matrix

Unit	Depends On	Can Parallel With
Unit 1: Core Editor Engine	— (no dependencies)	—
Unit 2: Document Management	Unit 1	—
Unit 3: Focus & Immersion	Unit 1	Unit 2, Unit 4, Unit 5
Unit 4: Image & Media	Unit 1, Unit 2	Unit 3, Unit 5
Unit 5: Export & Polish	Unit 1, Unit 2	Unit 3, Unit 4

Dependency Graph

Unit 1: Core Editor Engine
    |
    +---> Unit 2: Document Management
    |         |
    |         +---> Unit 4: Image & Media
    |         |
    |         +---> Unit 5: Export & Polish
    |
    +---> Unit 3: Focus & Immersion

Critical Path

Unit 1 --> Unit 2 --> Unit 5 --> Integration

Unit 1 (Core Editor Engine) is the sole blocker. Once Unit 1 is complete, Units 2-5 can be developed with moderate parallelism (Unit 3 needs only Unit 1; Units 4 and 5 need both Unit 1 and Unit 2).

Integration Points

From	To	Integration Type
Unit 1 → Unit 2	EditorViewModel uses MarkdownParser, EditorNodeModel, MarkdownRenderer	Direct code dependency
Unit 1 → Unit 3	WYSIWYGTextView exposes focus/typewriter methods	Same class extension
Unit 2 → Unit 4	MarkdownDocument provides assets directory; EditorViewModel inserts image references	Method calls via ViewModel
Unit 2 → Unit 5	EditorViewModel triggers export; SidebarView reads NSDocumentController	Method calls + framework API
Unit 1 → Unit 5	ExportService reuses MarkdownParser for HTML generation	Service reuse

Shared Components

Component	Used By Units	Ownership
C-03 EditorViewModel	1, 2, 3, 4	Unit 2 (created), extended by others
C-04 EditorSettings	2, 3, 5	Unit 2 (created), read by others
C-08 WYSIWYGTextView	1, 3, 4	Unit 1 (created), extended by Unit 3, 4
C-13 FileService	2, 4	Unit 2 (created), used by Unit 4