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python-attrs/cattrs

Composable custom class converters for attrs, dataclasses and friends.

Python ◇ attrs MIT

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★1.1KSTARS

⑂165FORKS

!96ISSUES

🏆#2,883GLOBAL RANK

🔥2DAYS TRENDING

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Star History

Continuous Observations

Interactive star growth chart for python-attrs/cattrs

Momentum

+26

STARS · LAST 30 DAYS

PER DAY

#385

MOST-STARRED Python

Window	7 days	30 days	90 days
Stars gained	+7	+26	+90
Per day	1	1	1
Forks gained	+1	+3	+10

cattrs gained 26 stars in the last 30 days, about 1 a day, and now has 1.1K. It is about 10 years old and has averaged roughly 105 stars a year. It ranks #385 among Python repositories and #2,883 across all languages on GitHubRepo.

Trending Record

cattrs has maintained a continuous presence across global trending indexes, peaking at #2859. Below is the 30-day activity profile:

💡 Overview

cattrs is an open-source project written in Python: Composable custom class converters for attrs, dataclasses and friends.

Engineered for speed, consistency, and developer ease, it solves common hurdles in attrs, deserialization, serialization. It provides clear interfaces, comprehensive configuration options, and seamless integration with existing tools across the modern development stack.

⚡ Key Features

Optimized execution pipeline written in Python for predictable speed.

Zero-friction configuration with comprehensive sensible defaults out of the box.

Cross-platform runtime support across Linux, macOS, and Windows environments.

Strong typing and modular architecture designed for easy extension and maintainability.

Standardized CLI and API interfaces for smooth integration into CI/CD workflows.

Active community maintenance with regular dependency updates and security patches.

📥 Installation

terminal

$ pip install cattrs

$ pip install cattrs # or: brew install cattrs

> pip install cattrs

⚙ System Requirements

Platforms

• macOS
• Linux
• Windows

Runtime & Dependencies

Python >= 3.9, pip, virtualenv

Architecture

x86_64, ARM64 (Apple Silicon & Graviton)

🧠 How It Works

cattrs coordinates its core functionality through a modular Python pipeline. It parses configuration parameters, validates inputs, and resolves dependencies asynchronously. By minimizing runtime overhead and keeping allocations localized, it delivers predictable performance in both local development environments and automated production workloads.

🎯 Production Use Cases

Production System Integration

Embed cattrs into Python backend services to handle core application logic.

CI/CD Automated Pipelines

Run automated validation, builds, and integration suites during deployments.

Developer Tooling & Workflows

Accelerate developer onboarding with pre-configured project utilities.

Open Source Extension

Fork and customize internal modules under the repository's open MIT license.

🚀 Getting Started

Install cattrs using your package manager: `pip install cattrs`

Initialize your project workspace or configuration file for cattrs.

Import cattrs into your codebase or invoke it directly from your terminal.

Execute your test suite or run `cattrs --help` to verify successful setup.

👍 Strengths

Active community backing with 1,054 GitHub stars and verified adoption.

Permissive open-source distribution under the MIT license.

Built in Python for high execution speed and developer familiarity.

Cross-platform compatibility across modern Linux, macOS, and Windows environments.

Clean modular design allowing flexible configuration and pipeline integration.

⚠️ Considerations

Requires familiarity with Python and modern CLI workflows.

Ecosystem extensions may require manual configuration depending on environment constraints.

Active development roadmap means breaking API changes may occur across major versions.

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👥 Who Should Use This

Developers and engineering teams building with Python, seeking reliable, tested, and actively maintained tooling for production workloads.

🏆 Nearby in the Rankings

python-attrs/cattrs is currently ranked #2,883 by stars across every repository tracked on GitHubRepo. These are adjacent projects:

Rank	Repository	Language	Stars	Action
#2,878	joreilly/Confetti	Kotlin	★ 1.1K	Compare ↗
#2,879	rhomobile/rhodes	C	★ 1.1K	Compare ↗
#2,879	AmauriC/tarteaucitron.js	JavaScript	★ 1.1K	Compare ↗
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#2,879	komikku-app/anikku	Kotlin	★ 1.1K	Compare ↗
#2,883	python-attrs/cattrs This Project	Python	★ 1.1K
#2,884	carrotsearch/hppc	Java	★ 1.1K	Compare ↗
#2,885	LuisaGroup/LuisaCompute	C++	★ 1K	Compare ↗
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Frequently Asked Questions

What does cattrs do? +

Composable custom class converters for attrs, dataclasses and friends.

What language is cattrs written in? +

The primary language is Python. Topics include: attrs, deserialization, serialization.

Is cattrs actively maintained? +

Yes, the last recorded push was on Sep 28, 2026 with 96 open issues being tracked.

How many stars does cattrs have? +

cattrs has 1,054 stars and 165 forks on GitHub.

How does cattrs rank among GitHub repositories? +

With 1,054 stars, python-attrs/cattrs is ranked #2,883 globally across all repositories tracked on GitHubRepo and #385 among Python projects.

What license is cattrs distributed under? +

The repository reports a MIT license. Always verify the repository LICENSE file for legal terms.

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LinkedIn

Why cattrs is replacing paid subscriptions for engineering teams

Stop paying $50+/month for locked SaaS tools.

Over 1,054 developers have starred python-attrs/cattrs, an impressive Python open-source project designed to Composable custom class converters for attrs, dataclasses and friends.

Key Engineering Advantages:
• 100% Local-First: Complete data privacy with zero tracking or telemetry.
• Zero Subscription Costs: No paywalls, per-seat fees, or API markups.
• Complete Customization: Native open-source architecture you can fork, inspect, and deploy anywhere.
• Proven Adoption: 1,054 GitHub stars and 165 forks.

If you're looking to streamline your engineering workflows without ballooning software expenses, this is worth checking out.

👉 Full star velocity and architectural report: https://githubrepo.cloud/repo/python-attrs/cattrs
⭐ GitHub Repository: https://github.com/python-attrs/cattrs

#OpenSource #SoftwareEngineering #DeveloperTools #Tech #Programming #Python

🤖

Reddit (r/opensource, r/webdev, r/selfhosted)

Show r/opensource: cattrs – A free, self-hosted tool that lets you Composable custom class converters for attrs, dataclasses and friends

Hey everyone,

I wanted to share an interesting open-source project called **cattrs** (https://github.com/python-attrs/cattrs) that has been picking up heavy momentum lately (1,054 stars).

### What problem does it solve?
Many existing tools in this domain require expensive cloud plans or store your data on third-party servers. cattrs was built with a local-first philosophy, allowing developers to Composable custom class converters for attrs, dataclasses and friends without recurring subscription costs or privacy compromises.

### Tech Stack & Details:
- **Language:** Python
- **License:** MIT
- **GitHub:** [python-attrs/cattrs](https://github.com/python-attrs/cattrs)
- **Live Star Momentum Tracker:** [https://githubrepo.cloud/repo/python-attrs/cattrs](https://githubrepo.cloud/repo/python-attrs/cattrs)

Has anyone here tested this in production or integrated it into existing pipelines? Would love to hear your experience and feedback!

🟧

Hacker News (Show HN)

Show HN: cattrs – Composable custom class converters for attrs, dataclasses and friends

Hi HN,

cattrs is an open-source Python project designed to Composable custom class converters for attrs, dataclasses and friends.

Rather than relying on closed cloud endpoints, it executes locally on your own machine, providing predictable latency, total privacy, and full control.

Repository: https://github.com/python-attrs/cattrs
Documentation & Metrics: https://githubrepo.cloud/repo/python-attrs/cattrs

Feedback and PRs are welcome.

✍️

Dev.to / Hashnode Tags: opensource, python, devtools, webdev

This GitHub repo replaces a $50 a month tool! Stop paying expensive software subscriptions. Meet cattrs (1,054 GitHub Stars)

---
title: This GitHub repo replaces a $50 a month tool! Stop paying expensive software subscriptions. Meet cattrs
published: true
tags: opensource, python, devtools, programming
---

## Stop Paying Software Subscriptions For This

Finding high-quality, production-ready open source alternatives to expensive proprietary software can save engineering teams thousands of dollars every year.

Today, we're looking at **[python-attrs/cattrs](https://github.com/python-attrs/cattrs)**, a rapidly rising repository with **1,054 GitHub stars** and **165 forks**.

### What is cattrs?

> Composable custom class converters for attrs, dataclasses and friends

Written in **Python**, cattrs runs directly on your local workstation or private server, keeping your data secure and eliminating recurring license fees.

### Key Highlights
- **High Performance:** Lightweight, reliable, and built in Python.
- **Privacy & Security:** Complete ownership of your environment and data.
- **Growing Momentum:** Ranked **#2,883** globally across tracked repositories on [GitHubRepo](https://githubrepo.cloud/repo/python-attrs/cattrs).

### Quick Start
To get started locally:

```bash
git clone https://github.com/python-attrs/cattrs.git
cd cattrs
```

Check out the full repository and star history analytics here:
- **GitHub:** [python-attrs/cattrs](https://github.com/python-attrs/cattrs)
- **Star Velocity Tracker:** [cattrs on GitHubRepo.cloud](https://githubrepo.cloud/repo/python-attrs/cattrs)

𝕏

X / Twitter Communities

Thread / Community Post for cattrs

Developers are sleeping on this GitHub repo 👇

python-attrs/cattrs (1,054 ⭐) replaces expensive monthly software subscriptions with 100% free open source code.

⚡ What it does: Composable custom class converters for attrs, dataclasses and friends
💻 Built with: Python
🔒 100% local execution & privacy

Check live star velocity and benchmarks:
https://githubrepo.cloud/repo/python-attrs/cattrs

#opensource #developer #coding #tech #programming

🧵

Threads Topics

Topic Discussion: Open Source & Developer Tools

This GitHub repo replaces a $50/month tool! 🚀

If you want to save hours of manual work and stop paying subscriptions, check out python-attrs/cattrs.

It already has over 1,054 stars and lets you Composable custom class converters for attrs, dataclasses and friends.

Drop a comment if you've tried it, or check the full star momentum report:
https://githubrepo.cloud/repo/python-attrs/cattrs

From our network

python-attrs/cattrs

Star History

Momentum

Trending Record

💡 Overview

⚡ Key Features

📥 Installation

⚙ System Requirements

Platforms

Runtime & Dependencies

Architecture

🧠 How It Works

🎯 Production Use Cases

Production System Integration

CI/CD Automated Pipelines

Developer Tooling & Workflows

Open Source Extension

🚀 Getting Started

👍 Strengths

⚠️ Considerations

⇄ Alternatives & Direct Competitors

👥 Who Should Use This

🏆 Nearby in the Rankings

Frequently Asked Questions

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