Dart & Flutter SDK Skills (dart-sdk-skills) 🎯

CI License: MIT

Authoritative, version-by-version agent skills for the Dart & Flutter SDKs: language features, core APIs, experimental feature flags (--enable-experiment), static metaprogramming (Macros & Augmentations), widget deprecations, Material 3 migrations, minSdk compatibility, and legacy codebase rescue (Dart 1.0 & Flutter 1.0 to modern Dart 3.x & Flutter 3.24+).

Designed to bridge LLM training cutoff gaps, ensuring AI coding agents (Claude Code, Google Antigravity, OpenAI Codex, GitHub Copilot, Cursor, Cline) write syntactically and semantically correct code across all target SDKs.

📦 Single-Command Universal Installation

Install both skills globally or into your local project workspace with any compatible package manager:

Option 1: Using npx skills (Node / universal)

# Install globally for all agents
npx skills add RandalSchwartz/dart-sdk-skills -g

# Or install for a specific project
npx skills add RandalSchwartz/dart-sdk-skills

Option 2: Using the Dart skills CLI

# Install globally
skills add https://github.com/RandalSchwartz/dart-sdk-skills --global --all

# Or install locally
skills add https://github.com/RandalSchwartz/dart-sdk-skills

Option 3: Manual Installation for Google Antigravity

Clone or symlink the skill directories into your Antigravity config:

git clone https://github.com/RandalSchwartz/dart-sdk-skills.git ~/Projects/Dart/dart-sdk-skills
ln -s ~/Projects/Dart/dart-sdk-skills/skills/dart-sdk-changelog ~/.gemini/config/skills/dart-sdk-changelog
ln -s ~/Projects/Dart/dart-sdk-skills/skills/flutter-sdk-changelog ~/.gemini/config/skills/flutter-sdk-changelog

🛠️ Included Skills

This repository bundles two top-level, progressively disclosed skills:

1. dart-sdk-changelog (Dart Language & Core APIs)

  • SKILL.md: Core router, activation triggers, and fast minSdk matrix.
  • macros-and-augmentations-guide.md: Syntax and mechanics for augment, augmented(), import augment, @JsonCodable(), and the 3-phase macro pipeline.
  • experimental-features-guide.md: Complete guide to --enable-experiment, Beta preview vs. stable-gated release tiers, and graduation history.
  • rescuing-legacy-dart-apps.md: 4-stage pipeline for migrating Dart 1.x & pre-2.12 codebases to modern Dart 3.x.
  • how-to-find-minsdk.md: Systematic methodology for finding minSdk lower bounds.
  • version-matrix.md: Searchable matrix mapping every feature and API to introducing Dart versions.
  • Version Reference Guides: Detailed breakdowns for Dart 2.x milestones and every Dart 3.x release (3.0 through 3.14).

2. flutter-sdk-changelog (Flutter Framework & Widgets)

  • SKILL.md: Fast widget & API replacement matrix.
  • widget-deprecations-and-replacements.md: Complete before/after dictionary (WillPopScope ➔ PopScope, Color.withOpacity ➔ Color.withValues, MaterialState ➔ WidgetState, 2021 TextTheme).
  • material-2-to-material-3-guide.md: Full M2 to M3 theming, ColorScheme.fromSeed, and component migration.
  • flutter-to-dart-version-matrix.md: Complete mapping from Flutter 1.0 to 3.27+ with bundled Dart SDKs and engine milestones.
  • rescuing-legacy-flutter-apps.md: 5-phase structured runbook for stepping legacy Flutter apps to modern Flutter.

🚀 Fast Language Feature Matrix

Feature / Syntax Minimum SDK Example Syntax
Primary Constructors 3.13.0 class Point(var int x, var int y); / this : assert(...)
Constructor Keyword Shorthands 3.13.0 new(this.x); / factory clone(...) => ...;
Private Named Parameters 3.12.0 Point({required this._x, required this._y});
Wildcard Variables (_) 3.7.0 var (_, b) = pair; / void fn(int _, int _)
Digit Separators 3.6.0 1_000_000, 0x4000_0000, 0.000_001
Extension Types 3.3.0 extension type Meters(int value) {}
Private Field Promotion 3.2.0 if (_privateFinalField != null) { ... }
Records & Tuples 3.0.0 (int, String) pair = (1, 'a');
Patterns & Destructuring 3.0.0 var (a, b) = pair; / if (json case {'id': int id})
Switch Expressions 3.0.0 var s = switch (e) { 0 => 'a', _ => 'b' };
Sealed Classes 3.0.0 sealed class State {}
Enhanced Enums 2.17.0 enum Status { ok(200); final int c; const Status(this.c); }
Super-Initializers 2.17.0 SubClass(super.name, {super.key});
Sound Null Safety 2.12.0 Sound static non-nullable types (?, late, !, required)

🎨 Fast Flutter Widget Replacement Matrix

Deprecated / Obsolete API Modern Replacement Target Flutter Version
Color.withOpacity(o) Color.withValues(alpha: o) Flutter 3.22+
MaterialState / MaterialStateProperty WidgetState / WidgetStateProperty Flutter 3.22+
WillPopScope PopScope(canPop: ..., onPopInvokedWithResult: ...) Flutter 3.12+
FlatButton, RaisedButton TextButton, ElevatedButton Flutter 2.0+
TextTheme.headline6, bodyText2 TextTheme.titleLarge, bodyMedium Flutter 3.7+
BottomNavigationBar NavigationBar (Material 3) Flutter 3.0+
ToggleButtons SegmentedButton<T> (Material 3) Flutter 3.7+

🤖 Maintenance & Agent Upgrade Runbook

For AI agents and maintainers updating this repo when new Dart or Flutter SDK versions are released, see AGENTS.md.

Local Validation & Quality Gates

# Verify static analysis & style standards
dart analyze --fatal-infos

# Run comprehensive link integrity and skill validation tests
dart test

# Refresh skill hashes & index in skills-lock.json
dart run tool/update_skills_index.dart

📄 License

MIT © 2026 Randal L. Schwartz