# DEPRECATION: Legacy setup.py install is deprecated. pip 24.0 will enforce this behaviour change. Please use pip install . instead.

- **ID:** `python/pip-legacy-setup-py-install-deprecated`
- **Domain:** python
- **Category:** install_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

A package or script invokes the legacy `setup.py install` command directly, which pip deprecated in favor of PEP 517 build backends.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 3.x | active | — | — |

## Workarounds

1. **** (95% success)
   ```
   Add a pyproject.toml with [build-system] requires = ['setuptools>=61', 'wheel'] and build-backend = 'setuptools.build_meta'. Then install with pip install .
   ```
2. **** (85% success)
   ```
   In CI, use pip<24 with a TODO to migrate; track the offending package and open an upstream issue.
   ```

## Dead Ends

- **** — Hides the warning but does not change the deprecated behavior; future pip versions will error. (80% fail)
- **** — Temporary and insecure; breaks other tooling expecting modern pip. (75% fail)
- **** — Does not change the deprecated code path being executed. (82% fail)