Parallel Fix Django

parallel-fix-django

Category: Parallel Development (Django)

Usage

/parallel-fix-django [--dimension <name>] [--dry-run]

Arguments

• --dimension: Optional - Focus on specific dimension (app-boundaries, shared-state, contracts, tests, docs, deps)
• --dry-run: Optional - Show what would be fixed without making changes

Purpose

Fix blockers identified by /parallel-ready-django to prepare the Django codebase for parallel multi-agent development. References the remediation-checklist.md from the skill.

Prerequisites

• Run /parallel-ready-django first
• .claude/readiness-report.md must exist with identified blockers

Execution Instructions for Claude Code

When this command is run, Claude Code should:

1. Read Readiness Report

cat .claude/readiness-report.md

Parse the "Blockers" and "Risks" sections to identify what needs fixing.

2. Fix by Dimension

App Boundaries Fixes

Problem: God App (>15 models)

1. Identify models that can be grouped by domain
2. Create new Django app: python manage.py startapp [domain] apps/[domain]
3. Move models incrementally with migrations
4. Update all imports
5. Verify tests pass

Problem: Circular Imports

# Before - circular import
from apps.orders.models import Order  # in users/models.py
from apps.users.models import User    # in orders/models.py

# After - use string reference
class Order(models.Model):
    user = models.ForeignKey("users.User",

Problem: Cross-App Imports >30%

1. Identify shared types/utilities
2. Create apps/shared/ app for common code
3. Move shared code to shared app
4. Update imports to use shared

Shared State Fixes

Problem: Cross-App Signals

# Before - implicit signal
@receiver(post_save, sender=User)
def create_user_stats(sender, instance, created, **kwargs):
    if created:
        UserStats.objects.create(user=instance)

# After - explicit service call
class UserService:
    def __init__(self, stats_service: StatsService):
        self.stats_service = stats_service

    def create_user(self, email: str, name: str) -> User:
        user = User.objects.create(email=email, name=name)
        self.stats_service.initialize_for_user(user.id)
        return user

Problem: Global Mutable State

# Before - global variable
_cache = {}

# After - use Django cache
from django.core.cache import cache

def get_cached_value(key: str):
    return cache.get(key)

API Contracts Fixes

Problem: Serializers with __all__

# Before
class UserSerializer(serializers.ModelSerializer):
    class Meta:
        model = User
        fields = "__all__"

# After - explicit fields
class UserSerializer(serializers.ModelSerializer):
    class Meta:
        model = User
        fields = ["id", "email", "name", "created_at"]
        read_only_fields = ["id", "created_at"]

Problem: No Mypy Configuration

Add to pyproject.toml:

[tool.mypy]
python_version = "3.11"
strict = true
plugins = ["mypy_django_plugin.main", "mypy_drf_plugin.main"]

[[tool.mypy.overrides]]
module = "*.migrations.*"
ignore_errors = true

[tool.django-stubs]
django_settings_module = "config.settings.local"

Install dependencies:

pip install django-stubs djangorestframework-stubs mypy

Problem: No OpenAPI

Add drf-spectacular:

pip install drf-spectacular

Update settings:

INSTALLED_APPS = [..., "drf_spectacular"]

REST_FRAMEWORK = {
    "DEFAULT_SCHEMA_CLASS": "drf_spectacular.openapi.AutoSchema",
}

SPECTACULAR_SETTINGS = {
    "TITLE": "Project API",
    "VERSION": "1.0.0",
}

Add URL:

from drf_spectacular.views import SpectacularAPIView

urlpatterns = [
    path("api/schema/", SpectacularAPIView.as_view(), name="schema"),
]

Test Infrastructure Fixes

Problem: No Pytest Setup

pip install pytest pytest-django factory-boy

Create conftest.py:

import pytest

@pytest.fixture(autouse=True)
def enable_db_access_for_all_tests(db):
    pass

Add to pyproject.toml:

[tool.pytest.ini_options]
DJANGO_SETTINGS_MODULE = "config.settings.test"
python_files = ["test_*.py"]
addopts = "-v --tb=short"

Problem: No Factories

Create apps/[app]/tests/factories.py:

import factory
from apps.users.models import User

class UserFactory(factory.django.DjangoModelFactory):
    class Meta:
        model = User

    email = factory.Sequence(lambda n: f"user{n}@example.com")
    name = factory.Faker("name")

Documentation Fixes

Problem: No CLAUDE.md

Create CLAUDE.md with Django conventions. Reference infrastructure-setup.md from skill for full template.

Problem: No Linting

Add to pyproject.toml:

[tool.ruff]
target-version = "py311"
line-length = 88
select = ["E", "W", "F", "I", "B", "C4", "UP"]

[tool.ruff.isort]
known-first-party = ["apps", "config"]

Run initial format:

pip install ruff
ruff format .
ruff check . --fix

Dependencies Fixes

Problem: Too Many Migrations

# Squash migrations
python manage.py squashmigrations [app] 0001 [last_migration]

Problem: Unpinned Dependencies

# Pin all dependencies
pip freeze > requirements.txt
# Or use poetry
poetry lock

3. Re-run Assessment

After fixes, suggest re-running assessment:

/parallel-ready-django

4. Report Results

Output:

🔧 Django Parallelization Fixes Applied

Fixed Issues:
✅ Converted 5 serializers from __all__ to explicit fields
✅ Added mypy configuration to pyproject.toml
✅ Created CLAUDE.md with Django conventions
✅ Added ruff linting configuration

Remaining Issues:
⚠️ 2 cross-app signals need manual review (apps/orders/signals.py)
⚠️ God app 'core' has 18 models - consider splitting

Next steps:
1. Review remaining issues manually
2. Run /parallel-ready-django to verify score improved
3. Target score ≥80 before running /parallel-decompose

Example

# Fix all blockers
/parallel-fix-django

# Fix only serializer issues
/parallel-fix-django --dimension contracts

# Preview changes without applying
/parallel-fix-django --dry-run

# After fixing, re-assess
/parallel-ready-django

Related Commands

• /parallel-ready-django - Run assessment first
• /parallel-setup - Ensure infrastructure exists
• /parallel-decompose - Create tasks after score ≥80