# ERROR: File "/tmp/pip-build-env-xxxx/overlay/lib/python3.11/site-packages/setuptools/build_meta.py", line 435, in get_requires_for_build_editable
    raise NotImplementedError("editable installs are not supported by this backend")

- **ID:** `python/pip-editable-install-fails-pep660`
- **Domain:** python
- **Category:** install_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

`pip install -e .` uses PEP 660 editable wheels, but the project's build backend (or an old setuptools) does not implement `build_editable`.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 3.9 | active | — | — |
| 3.10 | active | — | — |
| 3.11 | active | — | — |
| 3.12 | active | — | — |

## Workarounds

1. **** (90% success)
   ```
   Upgrade setuptools so PEP 660 is supported: `pip install --upgrade 'setuptools>=64'`, then `pip install -e .`.
   ```
2. **** (75% success)
   ```
   Fall back to legacy editable: `pip install -e . --config-settings editable_mode=compat` (setuptools) or switch the backend to one that supports PEP 660.
   ```

## Dead Ends

- **** — Still calls the backend's build_editable hook, which is unimplemented. (80% fail)
- **** — PEP 517 is already the default; the hook is missing regardless. (85% fail)