Principle:Pola rs Polars Python Binding Configuration
| Knowledge Sources | |
|---|---|
| Domains | Build_System, Python_Bindings |
| Last Updated | 2026-02-09 09:00 GMT |
Overview
Mechanism that configures the build system for generating Python extension modules from Rust code using PyO3 bindings with feature-gated functionality.
Description
Building Python bindings for a Rust library requires careful configuration of the build system to bridge two ecosystems. The Cargo manifest for the bindings crate must declare PyO3 as a dependency with the correct Python ABI version, specify all internal crate dependencies, and define feature flags that map to Python-accessible functionality. Platform-specific dependencies (memory allocators, system libraries) must be conditionally included. The feature system must mirror the upstream Rust library's feature organization while adding Python-specific features like the stable ABI version selector and runtime variant flags. This configuration determines what functionality is available in the compiled Python extension module.
Usage
Use this principle when creating Python bindings for Rust libraries using PyO3. The key design decisions are: which minimum Python version to target via the stable ABI, how to organize features to allow slim development builds, and how to handle platform-specific dependencies. The Polars approach of having a comprehensive feature system with a full default for production and selective features for development is effective for large libraries.
Theoretical Basis
Binding Configuration Pattern:
# Abstract configuration
python_bindings_config:
pyo3_abi: "abi3-py310" # Minimum Python version
internal_deps: [core, lazy, io, ops, ...] # Rust subcrates
features:
dtypes: [i8, i16, u8, u16, f16, array, ...]
operations: [rank, pivot, rolling, ...]
io: [csv, parquet, json, ipc, cloud, ...]
full = [dtypes, operations, io, optimizations]
platform_deps:
unix: jemalloc
windows: mimalloc
runtime_variants:
rt32: standard 32-bit index
rt64: 64-bit index (bigidx)
rtcompat: compatibility mode