# Break one circular dependency between modules

Two modules that import each other, separated so the build order is deterministic.

Category: Architecture and boundaries
Source: https://letsship.ai/use-cases/break-a-circular-dependency
Published: 2026-08-25

## Goal

Break one import cycle between two modules.

## Acceptance criteria

- The dependency graph has no cycle between the two modules
- Shared types or helpers move to a module both can depend on
- No behaviour changes, proven by the existing tests
- A rule blocks the cycle from returning

## What lands as proof

A dependency graph before and after, plus a rule that fails if the cycle is reintroduced.

## Prompt

Copy this to an agent to open the ticket:

```text
Create a Linear issue in my team and assign it to the SHIP agent.

Title: Break the cycle between {a} and {b}

Description: Break one import cycle between two modules.

Acceptance criteria:
- The dependency graph has no cycle between the two modules
- Shared types or helpers move to a module both can depend on
- No behaviour changes, proven by the existing tests
- A rule blocks the cycle from returning

Before you create the issue, run a dependency-graph check over this repository and replace {a} and {b} with a real cycle.
```

## Questions

### What does the agent actually change?

The ticket is scoped to one outcome: break one import cycle between two modules. Work that serves that outcome is in scope, and anything outside it is left for a separate ticket, so the pull request stays reviewable.

### How do I know the work is done?

The pull request carries the evidence, not only the diff. Here that means dependency graph acyclic, build order deterministic, so a reviewer can confirm the result without reproducing the work locally.

### How much oversight does this need?

The run stops once the plan is written. Somebody reads the approach and approves it before any code exists, which is the cheapest moment to redirect the work.