PyRank
jcrist

msgspec

A fast serialization and validation library, with builtin support for JSON, MessagePack, YAML, and TOML
PyPI GitHub

Shared Repository

This package shares its GitHub repository (jcrist/msgspec) with 1 other package. Stars, forks, and other GitHub metrics reflect the entire repository.
Downloads
Day
1.8M
Week
10.6M
Month
41.3M
Stars
3.8K
Forks
145
Issues
186
Version
0.21.1

Package Insights

What's this?
Score breakdown - each component scores 0-100, weighted by percentage
Maintenance
80
Popularity
71
Adoption
90
Community
60
How the maintenance status was determined
Last commit
31 days ago
Monthly downloads
41,267,860
Active
Activity within 30 days
• Stable
Activity within 31-180 days
Minimal
Activity within 181-365 days, or no activity data
At Risk
No activity for > 365 days, but > 10,000 monthly downloads
Archived
Repository flagged as archived on GitHub
How the popularity category was determined
Monthly downloads
41,267,860
Stars
3,755
Stars per 1k downloads
0.09
• Industry Standard
> 10,000,000 monthly downloads
Hidden Gem
< 0.5 stars per 1k downloads and > 100,000 monthly downloads
Community Favorite
> 5 stars per 1k downloads
Rising Star
Balanced ratio of stars to downloads
Unknown
Fewer than 1,000 monthly downloads, or no star data
How download momentum is calculated
Week daily avg
1,520,153
Month daily avg
1,375,595
Momentum
+10.5%
((week_daily_avg - month_daily_avg) / month_daily_avg) * 100
Python version support tiers
requires_python
>=3.10
Cutting Edge
Minimum supported version is 3.12 or newer
• Modern
Minimum supported version is 3.9, 3.10, or 3.11
Legacy
Supports 3.8 or older (or Python 2)
Unknown
No requires_python specified or unparseable
License categories
License
BSD-3-Clause
• Permissive
MIT, Apache, BSD, ISC, Unlicense, CC0, etc.
Copyleft
GPL, LGPL, AGPL, MPL, EPL, etc.
Proprietary
Commercial, all rights reserved, custom EULAs
Unknown
No license specified, or none of the above match
How the release cadence was determined
Last release
39 days ago
Total releases
40
Releases/year
7.6
Rapid
Last release within 365 days and > 12 releases/year
• Regular
Last release within 365 days
Slow
Last release 366-730 days ago
Stalled
Last release > 730 days ago, or no releases
Unknown
No usable release date available
How contributor risk was determined
Contributors
54
Monthly downloads
41,267,860
High Load
≤ 2 contributors and ≥ 50,000 monthly downloads
Moderate Load
< 10 contributors and ≥ 500,000 monthly downloads
Low Load
< 25 contributors and ≥ 5,000,000 monthly downloads, or sole maintainer with ≥ 10,000 monthly downloads
• Balanced
Enough contributors for the package's popularity
Unknown
No contributor data available
Engagement
54
 
Issue Burden
49.5
per 1k stars
Discussions
0.0
per 1k stars
Fork Ratio
37.2%
contrib / forks
Stale Release
No
 
PR Velocity
Quiet
 

Weekly Downloads

GitHub Stars

Not all downloads include detailed metadata. Breakdowns reflect the subset that does.

Downloads by OS

Linux 911.0K
macOS 11.6K
Windows 10.3K

Python Versions

3.12
32.9% 302.4K
3.11
28.0% 257.0K
3.10
22.3% 204.7K
3.13
9.5% 87.2K
3.14
7.3% 67.2K

Top Countries

1. US US
825.9K
2. DE DE
18.6K
3. SG SG
16.2K
4. NL NL
11.9K
5. IE IE
7.8K
6. GB GB
5.8K
7. FI FI
4.7K
8. JP JP
4.2K
9. CN CN
4.0K
10. IN IN
3.8K

GitHub Topics

Tags from the package's GitHub repository describing what it does.

Package Information

License
BSD-3-Clause
First Release
February 23, 2021
Last Release
1 month ago
Last Commit
1 month ago
Latest Version
0.21.1
Total Releases
40
Contributors
54
Open PRs
22
Archived
No
Python Versions
3.10 3.11 3.12 3.13 3.14
Wheels
cp310 cp311 cp312 cp313 cp314 cp38 cp39
Keywords
JSON MessagePack TOML YAML msgpack schema serialization validation
Tracking Since
January 6, 2026
Data Updated
May 17, 2026
Data Freshness
Fresh

Links