# WARNING: mypkg 1.0 does not provide the extra 'dev'

- **ID:** `python/setuptools-missing-extras-requires`
- **Domain:** python
- **Category:** config_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

The package metadata does not declare the requested extra in extras_require or [project.optional-dependencies], so pip installs only the base package.

## Version Compatibility

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

## Workarounds

1. **** (90% success)
   ```
   pip install mypkg pytest ruff mypy
   ```
2. **** (85% success)
   ```
   # in pyproject.toml
[project.optional-dependencies]
dev = ["pytest", "ruff"]
pip install -e '.[dev]'
   ```

## Dead Ends

- **** — --pre enables pre-releases but does not create extras that are not declared. (90% fail)
- **** — Upgrading does not add extras to the metadata; the warning persists. (85% fail)
- **** — If 'all' is not declared either, the same warning appears for 'all'. (70% fail)