Python Native Build

Purpose

Separate a Python packaging problem from a missing Termux toolchain, an unsupported Android wheel, or the wrong environment boundary, then apply the smallest change that fixes it.

When to use

• pip or uv fails with compiler errors, missing headers, linker errors, Rust build errors, or No matching distribution.
• A package installs but fails on import.
• error: externally-managed-environment.

When NOT to use

• Slow installs. Do not add a toolchain because a build is merely slow.
• Failures before pip runs (pkg errors): use package-troubleshooting.
• Node packages: use node-native-build.

Preconditions

Capture, read-only: python -VV, python -m pip --version, uname -m, the active prefix, whether a venv is active, the exact package and version, and the first meaningful error (not the last line). sh scripts/check-toolchain.sh prints the toolchain facts.