termui

An elite Flutter & Dart engineer persona. Use this agent for writing, reviewing, or fixing Dart/Flutter code according to strict MVVM architecture, high-performance rendering, and modern Dart semantics.

Guidelines and best practices for writing microbenchmarks, analyzing GC overhead, and evaluating performance on VM, JS, and WASM compilation targets.

Execute `dart analyze` to identify warnings and errors, and use `dart fix --apply` to automatically resolve mechanical lint issues. Use during development to ensure code quality and before committing changes.

Adds interactive widget previews to the project using the previews.dart system. Use when creating new UI components or updating existing screens to ensure consistent design and interactive testing.

Implement a component-level test using `WidgetTester` to verify UI rendering and user interactions (tapping, scrolling, entering text). Use when validating that a specific widget displays correct data and responds to events as expected.

Architects a Flutter application using the recommended layered approach (UI, Logic, Data). Use when structuring a new project or refactoring for scalability.

Fixes Flutter layout errors (overflows, unbounded constraints) using Dart and Flutter MCP tools. Use when addressing "RenderFlex overflowed", "Vertical viewport was given unbounded height", or similar layout issues.

Create model classes with `fromJson` and `toJson` methods using `dart:convert`. Use when manually mapping JSON keys to class properties for simple data structures.

Configure `MaterialApp.router` using a package like `go_router` for advanced URL-based navigation. Use when developing web applications or mobile apps that require specific deep linking and browser history support.

Add `flutter_localizations` and `intl` dependencies, enable "generate true" in `pubspec.yaml`, and create an `l10n.yaml` configuration file. Use when initializing localization support for a new Flutter project.

Use the `http` package to execute GET, POST, PUT, or DELETE requests. Use when you need to fetch from or send data to a REST API.

An elite software engineering workflow. Use this skill whenever you are asked to solve bugs, develop features, or optimize systems. It forces a strict Explore, Plan, Test, Execute, Verify methodology.

Use this skill to solve bugs or build features in Flutter or Dart. It combines the strict architectural rules of the codefu-persona with the rigorous step-by-step EPTEV debugging methodology of codefu-debugger.

Defines the Conventional Commits 1.0.0 specification for structured commit messages.

Deprecated. Replace the usage of `expect` and similar functions from `package:matcher` to `package:checks` equivalents by using the upstream `dart-migrate-to-checks-package` skill.

Deprecated. Best practices for creating high-quality, executable Dart CLI applications. Use the upstream `dart-build-cli-app` skill instead.

Best practices for validating Dart documentation comments. Covers using `dart doc` to catch unresolved references and macros.

Guidelines for handling long lines in Dart code to adhere to the 80-column rule. The `lines_longer_than_80_chars` lint.

Best practices for using `expect` and `package:matcher`. Focuses on readable assertions, proper matcher selection, and avoiding common pitfalls.

Guidelines for using modern Dart features (v3.0 - v3.10) such as Records, Pattern Matching, Switch Expressions, Extension Types, Class Modifiers, Wildcards, Null-Aware Elements, and Dot Shorthands.

Guidelines and best practices for refactoring consecutive prints, single-line string concatenations, and complex output blocks into triple-quoted multi-line string literals (''' or """) in Dart.

Guidelines for maintaining external Dart packages, covering versioning, publishing workflows, and pull request management. Use when updating Dart packages, preparing for a release, or managing collaborative changes in a repository.

Understand and improve test coverage in a Dart package. Helps agents run coverage, interpret results, and identify missed lines.

Core concepts and best practices for `package:test`. Covers `test`, `group`, lifecycle methods (`setUp`, `tearDown`), and configuration (`dart_test.yaml`).