---
id: cyclic
version: "1.0.0"
license: BSD
license_treatment: permissive
maintenance: abandoned
---

# cyclic — Handle cyclic relations

License: permissive · Maintenance: abandoned · Downloads: 127.7K/mo

## What it is and what it does

Cyclic is a lightweight library for detecting cycles in directed graphs where relationships are compared by value. It provides a simple API to add edges between nodes and check whether a given node participates in any cyclic relationship. The package has no external dependencies, making it trivial to install.

The library is designed for scenarios where you need to track parent-child or dependency relationships and verify that no circular chains exist. It stores relationships and can query whether adding a new edge would create a cycle. However, the package has been unmaintained since 2018 with no updates or bug fixes in over five years, so it should be considered stable but not actively developed.

Use it for:

- Validate that a new dependency relationship won't introduce a circular dependency in a package or module system.
- Check for cycles in organizational hierarchies or permission delegation chains before committing a relationship.
- Detect circular imports or module dependencies during static analysis of Python codebases.
- Verify acyclic constraints in workflow or task scheduling systems before execution.

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

Detects and reports cyclic relationships in a directed graph by checking whether adding a new edge would create a cycle.

Yes, if you need basic cycle detection in a small, self-contained graph and can tolerate no ongoing maintenance. The zero-dependency design and permissive license make it safe to embed. No, if you need active support, performance at scale, or assurance that edge cases are handled—consider a more actively maintained graph library instead.

## Install

pip install cyclic
uv add cyclic
poetry add cyclic

## Installing cyclic

Before you install: Installation is frictionless with no runtime dependencies, but the package has been abandoned since its single release on 2018-09-26 with no commits after 2020-05-27, so expect no maintenance or bug fixes.

License in practice: BSD license is permissive, allowing commercial and private use with minimal restrictions—suitable for most projects.

Quickstart:

pip install cyclic

from cyclic import Cyclic

cy = Cyclic()
cy.add('B', 'A')
cy.add('C', 'B')
cy.add('A', 'C')
print(cy.is_cyclic('C'))  # True

Verify before relying:

- Whether the package correctly handles all edge cases in cycle detection (e.g., self-loops, disconnected components).
- Performance characteristics with large graphs or high-frequency cycle checks.
- Compatibility with modern Python versions beyond the unspecified support claim.

## Package facts

- License: BSD (permissive)
- Python support: unspecified
- Install friction: low
- Maintenance: abandoned
- Downloads: 127.7K/month (top 15,000 on PyPI)
- Known vulnerabilities: none known

## Tags

cyclic dependency detection, circular relation checker, graph cycle detection, cyclic relation handler, directed graph cycles, dependency cycle finder, circular reference detection, graph-algorithms, cycle-detection, unmaintained

[View on SkillFed](https://skillfed.io/packages/cyclic) · [View on PyPI](https://pypi.org/project/cyclic/)