---
id: msgspec
version: "0.21.1"
license: BSD-3-Clause
license_treatment: permissive
maintenance: active
---

# msgspec — A fast serialization and validation library, with builtin support for JSON, MessagePack, YAML, and TOML.

License: permissive · Maintenance: active · Popularity: top 1,000 on PyPI

## Install

pip install msgspec
uv add msgspec
poetry add msgspec

## Description

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[![Code...

## AI interpretation — verify before relying

msgspec is a fast serialization and validation library supporting JSON, MessagePack, YAML, and TOML with zero-cost schema validation using Python type annotations and a high-performance Struct type for structured data.

Verdict: msgspec is a mature, actively maintained serialization library (4007 GitHub stars, top 1000 PyPI tier) with no known vulnerabilities, permissive licensing, and zero runtime dependencies. Medium install friction is offset by comprehensive pre-built wheels and strong performance benchmarks. Suitable for production use where fast JSON/MessagePack handling and schema validation are priorities.

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