Circular Dependencies

Find and break import cycles — the class of bugs where module A imports B which imports A (directly or through a chain), causing one module to be partially initialized when the other loads. The goal: a directed acyclic import graph where every module's dependencies are fully initialized before it runs.

When to Apply This Skill

Trigger on any of:

• undefined value at import time that is defined correctly inside the module
• ReferenceError: Cannot access 'X' before initialization
• Jest/Vitest warning: Jest has detected the following N circular dependencies
• webpack warning: WARNING in Circular dependency detected
• Test behavior that changes depending on which test file runs first
• TypeError: Class extends value undefined (classic circular class inheritance)
• An import that works in isolation but fails inside the full application