MigrationError: Circular dependency detected

MigrationError: Circular dependency detected

$ python manage.py migrate
django.db.migrations.exceptions.CircularDependencyError: app1.0002 -> app2.0001 -> app1.0002

Why this happens

Migrations depend on each other via ForeignKeys or RunPython that require models from the other app.

Fix

Split migrations, use swappable_dependency, or refactor to remove cycle; combine operations into a single app or migration.

Wrong code

# app1 0002 depends on app2 0001
# app2 0001 depends on app1 0002

Fixed code

# Remove one dependency chain and create linear order
# e.g., app2 0001 depends on app1 0001 only