pymsix

Cross-platform Python library for creating, extracting and signing MSIX packages. Wraps makeappx.exe (Windows) or makemsix (Linux) — binaries are resolved automatically.

Requirements

• Python 3.10+

Platform	Requirements
Windows	Windows 10 SDK
Linux	osslsigncode (for signing)

On Linux, makemsix is bundled with the package.

Installation

pip install pymsix

After installing on Linux, make the bundled binary executable:

chmod +x venv/lib/{python version}/site-packages/msix/bin/makemsix

Usage

from msix import MsixPacker

packer = MsixPacker()
packer.pack("path/to/app-content/", "output/MyApp.msix")
packer.unpack("output/MyApp.msix", "path/to/extracted/")

The app-content/ directory must contain a valid AppxManifest.xml.

Signing

packer.sign("output/MyApp.msix", "cert.pfx", pfx_password="s3cr3t")

API

MsixPacker(binary=None, sign_binary=None, verbose=False)

Parameter	Description
binary	Path to makeappx.exe (Windows) or makemsix (Linux). Auto-resolved if omitted.
sign_binary	Path to signtool.exe (Windows) or osslsigncode (Linux). Auto-resolved if omitted.
verbose	Print the command being executed.

pack(content_dir, output_package, *, overwrite=True, skip_validation=False, hash_algorithm="SHA256")

Creates an MSIX package from a directory. Returns the path to the created file.

Note: overwrite, skip_validation, and hash_algorithm are only supported on Windows (makeappx.exe). These parameters are silently ignored on Linux, as makemsix does not support them.

unpack(package, output_dir, *, overwrite=True)

Extracts an MSIX package into a directory. Returns the path to the extraction directory.

Note: overwrite is only supported on Windows (makeappx.exe). This parameter is silently ignored on Linux, as makemsix does not support it.

sign(package, pfx, *, pfx_password=None, timestamp_url="http://timestamp.digicert.com", digest_algorithm="SHA256")

Signs an MSIX package in-place using a PFX certificate. Returns the path to the signed file.

On Windows, signtool.exe is used (auto-detected from the Windows SDK). On Linux, osslsigncode must be installed:

# Debian/Ubuntu
sudo apt install osslsigncode

# Fedora/RHEL
sudo dnf install osslsigncode

Parameter	Description
package	Path to the .msix file to sign.
pfx	Path to the .pfx certificate file.
pfx_password	Password for the .pfx file. Omit if not password-protected.
timestamp_url	RFC 3161 timestamp server URL. Set to "" to disable timestamping.
digest_algorithm	Digest algorithm for the signature (default "SHA256").

Binary Resolution Order

Pack binary (makeappx.exe / makemsix)

1. binary constructor argument
2. PYMSIX_BINARY environment variable
3. Windows SDK makeappx.exe (Windows only)
4. Bundled makemsix binary (Linux only)

Sign binary (signtool.exe / osslsigncode)

1. sign_binary constructor argument
2. PYMSIX_SIGN_BINARY environment variable
3. Windows SDK signtool.exe (Windows only)
4. osslsigncode on PATH (Linux only)

License

MIT