attrs

Classes Without Boilerplate

attrs Permissive license MIT Active v26.1.0 released 2026-03-19

Install

attrs on PyPI

pip

pip install attrs

uv

uv add attrs

poetry

poetry add attrs

Package facts

License	MIT (permissive)
Python support	supports the current Python release (>=3.9)
Install friction	low — pure-Python wheel
Runtime dependencies	none
Maintenance	actively maintained — 147 days since the last release
First released	2015-02-21
Popularity	one of the 100 most-downloaded packages on PyPI (30-day window, as of 2026-08-13)
Known vulnerabilities	none known (OSV.dev, checked 2026-08-13)

Evidence: attrs-26.1.0-py3-none-any.whl

Keywords: attribute, boilerplate, class

Development Status :: 5 - Production/StableProgramming Language :: Python :: 3.10Programming Language :: Python :: 3.11Programming Language :: Python :: 3.12Programming Language :: Python :: 3.13Programming Language :: Python :: 3.14Programming Language :: Python :: 3.9Programming Language :: Python :: Implementation :: CPythonProgramming Language :: Python :: Implementation :: PyPyTyping :: Typed

About attrs

from the package's own PyPI description — quoted content, verbatim

attrs is the Python package that will bring back the joy of writing classes by relieving you from the drudgery of implementing object protocols (aka dunder methods). Trusted by NASA for Mars missions since 2020!

Its main goal is to help you to write concise and correct software without slowing down your code.

AI interpretation — verify before relying

AI-generated interpretation of the package facts above; every digit, version, license, or vulnerability id it cites is grounded in the facts already shown on this page

attrs is a Python library that automatically generates boilerplate methods like `__init__`, `__repr__`, and `__eq__` for classes, letting you define attributes declaratively with type annotations or field descriptors.

Installation is frictionless: attrs is a pure-Python package with no runtime dependencies, distributed as a wheel, and actively maintained with a recent release (147 days ago).

attrs is licensed under MIT, a permissive license that allows commercial and private use with minimal restrictions—suitable for most projects.

Usage

pip install attrs

from attrs import define, Factory

@define
class Point:
    x: int
    y: int = 0

p = Point(1, 2)
print(p)  # Point(x=1, y=2)

Requires Python 3.9 or later.

Verdict: attrs is a mature, zero-dependency library (top 100 on PyPI) with active maintenance, no known vulnerabilities, and permissive licensing. It is production-ready and trusted by NASA; the main decision is whether declarative class generation fits your codebase's style.

Needs verification

Performance characteristics compared to standard dataclasses or manual implementations for your specific use case.
Whether the modern `@define` API or classic `@attr.s` API is recommended for new projects.

python class boilerplate generatordataclass alternativeautomatic dunder methodsdeclarative class attributesreduce class boilerplate codepython object protocol automationtyped class definitions