---
id: python-interface
version: "1.6.1"
license: Apache 2.0
license_treatment: permissive
maintenance: abandoned
---

# python-interface — Pythonic Interface definitions

License: permissive · Maintenance: abandoned · Downloads: 575.6K/mo

## What it is and what it does

python-interface provides a way to define interfaces in Python and verify at class definition time that implementations satisfy those interfaces. It wraps Python's abstract base class (abc) module with a stricter, more explicit API that aims to catch interface violations earlier and report them more clearly.

The package is a lightweight, dependency-free library that works by declaring interface contracts and then checking that concrete classes properly implement them. It's designed for developers who want compile-time-like interface checking in a dynamically-typed language, similar to protocols or interfaces in statically-typed languages.

Use it for:

- Enforce strict interface contracts in large codebases where implicit duck-typing leads to hard-to-debug errors
- Document expected method signatures and behavior for plugin or extension systems
- Catch interface violations at class definition time rather than at runtime call sites
- Replace or augment abc module when you need clearer error messages for interface mismatches

## Worth the install?

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

Declares interfaces and statically asserts that classes implement them, offering stricter semantics and better error messages than Python's built-in abc module.

No. The package is abandoned (last release 2021-04-21, no commits since) and lacks support for modern Python versions. While the Apache 2.0 license is permissive and there are no known vulnerabilities, the high install friction combined with zero maintenance makes it a poor choice for new projects. Consider Python's built-in abc or typing.Protocol instead.

## Install

pip install python-interface
uv add python-interface
poetry add python-interface

## Installing python-interface

Before you install: High install friction and abandoned maintenance status since 2021-04-21—no updates in years. The package is marked Production/Stable but receives no active support or bug fixes.

License in practice: Apache 2.0 permissive license allows commercial and private use with minimal restrictions, suitable for most projects.

Quickstart:

pip install python-interface

from interface import Interface, implements

class MyInterface(Interface):
    def my_method(self): pass

@implements(MyInterface)
class MyClass:
    def my_method(self):
        return 'implemented'

Package is abandoned and untested on Python versions beyond 3.8; compatibility with recent Python releases is unverified.

Verify before relying:

- Whether the package works reliably with Python versions beyond 3.8, given its last release predates modern Python releases
- Whether static assertion behavior matches current abc module semantics in recent Python versions
- Real-world adoption and maintenance burden if issues arise in production use

## Package facts

- License: Apache 2.0 (permissive)
- Python support: unspecified
- Install friction: high
- Maintenance: abandoned
- Downloads: 575.6K/month (top 15,000 on PyPI)
- Known vulnerabilities: none known

## Tags

interface declaration python, static interface checking, protocol enforcement, abstract base class alternative, interface validation, pythonic interface definitions, class contract checking, interface-checking, abandoned

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