Flutter/Dart Code Review

Curated by Skill Harbor: a comprehensive, library-agnostic code review checklist for Flutter and Dart that works whatever state management the project uses. Fifteen review areas: project health (folder structure, separation of concerns, clean pubspec, strict analysis_options), Dart language pitfalls (implicit dynamic, null safety misuse, catching Error, late overuse, print in production, missing Dart 3 pattern matching), widget best practices (decomposition under 80 to 100 line build methods, const constructors, key usage, theming from colorScheme not hardcoded colors, no work in build()), state management principles that adapt to BLoC, Riverpod, Provider, GetX, MobX, and Signals (business logic out of widgets, immutable state with copyWith or proper reactive mutation, sealed types instead of boolean flag soup, narrow rebuild scopes, disposal hygiene, mounted checks after async gaps), performance (const to stop rebuilds, no expensive work in build, image caching, ListView.builder, deferred loading), testing (unit, widget, integration, golden tests, 80%+ on business logic), accessibility (semantics, contrast, 48px targets, no color-only state), platform concerns (iOS/Android differences, responsive layouts), security (secure storage, no hardcoded API keys, input validation, HTTPS), package review (pub points, verified publishers, version constraints), navigation and routing, error handling (FlutterError.onError, Crashlytics/Sentry, graceful degradation), internationalization, dependency injection, and static analysis enforcement. Includes a quick-reference table mapping each principle to its implementation per state management solution. Use when reviewing Flutter or Dart code, regardless of the libraries involved. By @affaan-m, listed here with credit to its creator. From the affaan-m/ECC repository (MIT). Honest caveats: a checklist, not a substitute for running the app on real devices; opinions on state management are deliberately neutral, your team's chosen solution still needs its own depth; 15 areas is a lot, prioritize by risk. Skill Harbor never reviews the code, review it yourself before use.