The role of C++ in the Python ecosystem: the case of the Qt framework — Cristián Maureira-Fredes

Qt is a mature cross-platform UI framework with Python bindings through PySide (Qt for Python) and PyQt implementations

PySide6 offers modern features like:

• NumPy array support
• Snake case API (alternative to Qt’s CamelCase)
• Android deployment support
• WebAssembly capabilities
• Cross-platform deployment

Qt is widely used in industry applications:

• Medical devices
• Automotive interfaces
• Aviation systems
• Industrial equipment
• Desktop applications

The Python-C++ integration is handled through binding generation:

• Uses the Python limited API for better compatibility
• Supports multiple Python versions
• Minimizes dependency complexities
• Enables native performance

Key advantages of Qt for Python:

• Native look and feel across platforms
• Rich set of widgets and controls
• QML support for modern interfaces
• Professional-grade deployment options
• LGPL licensing option

Challenges in the ecosystem:

• Complex build system requirements
• Large binary sizes
• Compilation overhead
• Learning curve with C++ concepts

Alternative Python UI frameworks exist (Kivy, Toga) but Qt offers industrial-strength features and stability

The project emphasizes Python ecosystem integration while maintaining Qt’s professional capabilities

Current development focus is on QML integration over traditional widgets

Deployment solutions include specialized tools for creating standalone applications without freezing Python code