1.3.16

Release Date: 2025-07-10
Version: 1.3.16

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Compatibility and Wheel Support

This release provides binary wheels that are fully compatible with lxml v6.0.0. The compatibility is ensured by using the same underlying libxml2 version in both python-xmlsec and lxml.

Because of this strict requirement, the wheels cannot be used with versions of lxml lower than 6.0.0. Mixing versions will lead to runtime errors.

Common Error

If you see the following message:

lxml & xmlsec libxml2 library version mismatch

it indicates that the version of libxml2 used to build lxml does not match the version used to build python-xmlsec.

Recommended Solutions

• Upgrade lxml to v6.0.0, or
• Build both lxml and python-xmlsec manually from source using the same libxml2 version

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Wheel Build Configuration

Linux and macOS Wheels

These wheels are built against the following versions, which match those used in lxml v6.0.0:

• libxml2 v2.14.4
• libxslt v1.1.43
• xmlsec1 v1.3.7

Windows Binary Wheels

The Windows binary wheels were compiled using Visual Studio 2022 and include the following libraries:

• iconv v1.18-1
• libxml2 v2.11.9-3
• libxslt v1.1.39
• openssl v3.0.16.pl1
• xmlsec v1.3.7
• zlib v1.3.1

These versions are compatible with those used in lxml v6.0.0.

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Acknowledgements

Special thanks to @TomiBelan for helping with the creation of binary wheels for this release.