Flutter Subagent-Driven Development
Execute plan by dispatching fresh subagent per task, with two-stage review after each: spec compliance review first, then code quality review.
Core principle: Fresh subagent per task + two-stage review = high quality Flutter code, fast iteration
Announce at start: "I'm using the flutter-subagent-dev skill to execute this plan."
When to Use
Have implementation plan?
├─ NO → Use flutter-brainstorming first
└─ YES → Tasks mostly independent?
├─ NO → Tightly coupled → Use flutter-executing instead
└─ YES → Stay in this session?
├─ YES → Use flutter-subagent-dev (this skill)
└─ NO → Use flutter-executing (parallel session)vs. Flutter Executing (batch mode):
- Same session (no context switch)
- Fresh subagent per task (no context pollution)
- Two-stage review after each task
- Faster iteration
The Process
1. Read plan, extract all tasks, create TodoWrite
↓
2. For each task:
├─ Dispatch implementer subagent
├─ Implementer asks questions? → Answer, then proceed
├─ Implementer implements, runs flutter analyze, commits
├─ Dispatch spec reviewer subagent
├─ Spec compliant?
│ ├─ NO → Implementer fixes, re-review
│ └─ YES → Continue
├─ Dispatch code quality reviewer subagent
├─ Quality approved?
│ ├─ NO → Implementer fixes, re-review
│ └─ YES → Mark task complete
└─ Next task
↓
3. After all tasks:
├─ Dispatch final code reviewer
└─ Use flutter-finishing skillSubagent Prompt Templates
Implementer Subagent
You are implementing Task N: [task name]
## Task Description
[Full task text from plan - copy exactly]
## Context
- Project: Flutter app using [BLoC/Provider/Riverpod]
- Architecture: Clean Architecture
- This task is part of: [feature name]
- Previous tasks completed: [list]
- Dependencies: [what this task depends on]
## Layer
[Domain / Data / Presentation / Test]
## Before You Begin
If you have questions about:
- Clean Architecture placement
- State management approach
- Widget composition
- Test strategy
Ask before implementing.
## Your Job
1. Implement exactly as specified in task
2. Run `flutter analyze` - must show no issues
3. Commit with conventional commit message
4. Self-review: Check against task requirements
5. Report what you implemented
## Verification
After implementation:
$ flutter analyze lib/features/<feature>/
Expected: No issues found!Spec Reviewer Subagent
You are reviewing whether an implementation matches its specification.
## What Was Requested
[Full task requirements from plan]
## What Implementer Claims They Built
[From implementer's report]
## CRITICAL: Do Not Trust the Report
Verify everything independently by reading actual code.
**DO NOT:**
- Take their word for what they implemented
- Trust claims about completeness
- Accept their interpretation of requirements
**DO:**
- Read the actual code they wrote
- Compare actual implementation to requirements line by line
- Check for missing pieces
- Look for extra features not in spec
## Your Job
Read the implementation code and verify:
**Missing requirements:**
- Did they implement everything requested?
- Are there requirements they skipped?
**Extra/unneeded work:**
- Did they build things not requested?
- Did they add "nice to haves" not in spec?
**Flutter-Specific Checks:**
- Is the layer correct (Domain/Data/Presentation)?
- Does Clean Architecture structure match?
- Are dependencies pointing correct direction?
**Report:**
- ✅ Spec compliant (everything matches after code inspection)
- ❌ Issues found: [list specifically what's missing or extra, with file:line references]Code Quality Reviewer Subagent
You are reviewing Flutter code quality after spec compliance is confirmed.
## What Was Implemented
[Description]
## Git Range to Review
Base: {BASE_SHA}
Head: {HEAD_SHA}
## Flutter Code Quality Checklist
**Clean Architecture:**
- [ ] Proper layer separation (Domain/Data/Presentation)
- [ ] Dependencies point inward
- [ ] No framework imports in Domain layer
**State Management:**
- [ ] Appropriate pattern for complexity
- [ ] Proper state transitions
- [ ] Error state handling
**Widget Quality:**
- [ ] StatelessWidget preferred when possible
- [ ] Proper const usage
- [ ] No deeply nested trees
**Dart Style:**
- [ ] flutter analyze clean
- [ ] Effective Dart followed
- [ ] Proper null safety
**Tests:**
- [ ] Priority 1 tests (Repository/DataSource) present
- [ ] Priority 2 tests (State) present if applicable
- [ ] Tests actually test logic (not just mocks)
## Output Format
### Strengths
[What's well done?]
### Issues
#### Critical (Must Fix)
[Bugs, security issues, broken functionality]
#### Important (Should Fix)
[Architecture problems, missing features, test gaps]
#### Minor (Nice to Have)
[Style, optimization]
### Assessment
**Ready to proceed?** [Yes/No/With fixes]Example Workflow
You: I'm using Flutter Subagent-Driven Development to execute this plan.
[Read plan: docs/plans/auth-plan.md]
[Extract all 5 tasks with context]
[Create TodoWrite with all tasks]
Task 1: User Entity (Domain Layer)
[Dispatch implementer subagent with full task text]
Implementer: "Implementing User entity in domain layer..."
- Created lib/features/auth/domain/entities/user.dart
- flutter analyze: No issues found!
- Committed: "feat(auth): add User entity"
[Dispatch spec reviewer]
Spec reviewer: ✅ Spec compliant - User entity matches requirements
[Dispatch code quality reviewer]
Code reviewer:
Strengths: Clean entity, proper const constructor
Issues: None
Assessment: Approved
[Mark Task 1 complete]
Task 2: AuthRepository Interface (Domain Layer)
[Dispatch implementer subagent]
Implementer: "Question: Should login return Either<Failure, User> or just User?"
You: "Use Either<Failure, User> pattern with dartz package"
Implementer: "Got it. Implementing..."
- Created auth_repository.dart with Either return types
- flutter analyze: No issues found!
- Committed
[Dispatch spec reviewer]
Spec reviewer: ❌ Issues:
- Missing: logout() method specified in plan
- Extra: Added refreshToken() not in spec
[Implementer fixes]
Implementer: Added logout(), removed refreshToken()
[Spec reviewer reviews again]
Spec reviewer: ✅ Spec compliant
[Dispatch code quality reviewer]
Code reviewer: ✅ Approved
[Mark Task 2 complete]
... (continue for remaining tasks)
[After all tasks]
[Dispatch final code reviewer for entire feature]
[Use flutter-finishing skill]Red Flags
Never:
- Skip reviews (spec compliance OR code quality)
- Proceed with unfixed issues
- Start code quality review before spec compliance ✅
- Let implementer skip
flutter analyze - Ignore subagent questions
If subagent asks questions:
- Answer clearly about Clean Architecture placement
- Clarify state management approach
- Provide context about existing patterns
If reviewer finds issues:
- Implementer fixes them
- Reviewer reviews again
- Repeat until approved
REQUIRED SUB-SKILL
After all tasks complete: → flutter-craft:flutter-finishing (present completion options)