Added #

• Screenshot in README.md via golden test
• GitHub Actions CI workflow for automated testing
• Codecov integration for coverage reporting
• Roboto font bundled for consistent text rendering

Fixed #

• Resolved all dart analyzer warnings in lib/ and test/
• Fixed installation instructions to use pub.dev version
• Golden tests excluded from CI (platform-dependent font rendering)

Changed #

• README badges: pub.dev version, license, CI status, coverage

Added #

• Example application with 50,000 rows of sample sales data
• Performance benchmarks for tile rendering (< 8ms target)
• Performance benchmarks for hit testing (< 100μs target)
• Scroll performance benchmarks
• Large dataset integration tests
• Memory leak tests
• Comprehensive documentation suite:
  • ARCHITECTURE.md with rendering pipeline deep dive
  • GETTING_STARTED.md with installation and basic usage
  • COOKBOOK.md with practical recipes
  • PERFORMANCE.md optimization guide
  • THEMING.md customization guide
  • TESTING.md testing patterns
  • API.md quick reference
• Updated PLAN.md to reflect completed implementation

Changed #

• Version bumped to 1.0.0 for production release

Added #

• WorksheetWidget - Main public StatefulWidget
• WorksheetController - Programmatic control aggregating sub-controllers
• WorksheetThemeData - Complete theming and styling support
• WorksheetTheme - InheritedWidget for theme propagation
• Complete public API exports in worksheet.dart
• Gesture handling integration
• Layer composition using Stack

Added #

• RenderLayer - Abstract interface for render layers
• SelectionLayer - Selection highlight painting
• SelectionRenderer - Selection visual rendering
• HeaderLayer - Row and column header layer
• HeaderRenderer - A,B,C column and 1,2,3 row labels
• FrozenLayer - Infrastructure for frozen panes (not fully wired)

Added #

• EditController - Cell editing orchestration with start/commit/cancel flow
• EditTrigger enum - Double-tap, keyboard, and typing triggers
• CellEditorOverlay - Floating text editor widget for cell editing

Added #

• SelectionController - Selection state machine with single/range/row/column modes
• HitTester - Coordinate resolution from screen to worksheet space
• HitTestResult - Types for cell, header, and resize handle hits
• GestureHandler - Unified gesture processing
• KeyboardHandler - Arrow keys and keyboard shortcuts
• ScaleHandler - Pinch-to-zoom gesture handling

Added #

• ZoomController - Zoom level management extending ValueNotifier
• Support for 10%-400% zoom range (0.1 to 4.0)
• zoomIn(), zoomOut(), and reset() methods
• Zoom clamping and validation

Added #

• ScrollAnchor - Position preservation during zoom
• WorksheetScrollPhysics - Custom scroll momentum physics
• ViewportDelegate - Interface for viewport management
• WorksheetViewport - TwoDimensionalScrollable integration
• WorksheetScrollDelegate - Child management for 2D scrolling

Added #

• TileCoordinate - Tile grid position representation
• TileConfig - Configuration with 256px tiles, LRU cache settings
• Tile - Single cached tile with GPU-backed ui.Picture
• TilePainter - Cell painting with level-of-detail (LOD) rendering
• TileCache - LRU eviction cache for tiles
• TileManager - Tile lifecycle orchestration

Performance #

• GPU-backed tile caching for smooth scrolling
• Level-of-detail rendering based on zoom level
• LRU cache eviction to manage memory

Added #

• WorksheetData - Abstract interface for worksheet data access
• SparseWorksheetData - Map-based sparse storage implementation
• DataChangeEvent - Granular change events for reactive updates
• SpanList - Cumulative row/column sizes with O(log n) lookups
• LayoutSolver - Position to index conversion
• VisibleRangeCalculator - Viewport to CellRange queries
• ZoomTransformer - Zoom-aware coordinate math with ZoomBucket enum

Performance #

• O(log n) binary search for position lookups
• Memory-efficient sparse data storage

Added #

• Initial project scaffolding
• CellCoordinate - Immutable (row, col) address with Excel notation (A1, AA100)
• CellRange - Rectangular cell selection with normalization and contains()
• CellValue - Union type supporting text, number, boolean, formula, error, date
• CellStyle - Font, color, alignment, and border styling
• FreezeConfig - Configuration for frozen panes
• Full test coverage for all core models
• CLAUDE.md development guide
• PLAN.md implementation plan

Technical #

• TDD workflow with tests written before implementation
• SOLID principles applied throughout
• Immutable models with proper equality/hashCode