Fallbacks

A fallback occurs when Pyvorin cannot compile a Python construct to native code and instead runs it through CPython. Fallbacks keep your program correct and runnable.

Common fallback reasons

• Dynamic type changes the compiler cannot track.
• Unsupported builtin or stdlib function.
• Runtime import through __import__ or a dynamic path.
• Use of exec or eval.
• C extension ABI dependencies.

Inspecting fallbacks

pyvorin compile app.py --report
pyvorin fallback-summary

Fallbacks are expected behaviour. They do not indicate a bug. A program with fallbacks still benefits from the parts that compiled natively.