# Stack and Dependencies

## Rules
- Primary language: Python >=3.13 (evidence: pyproject.toml requires-python = ">=3.13")
- Application: Streamlit app (streamlit >=1.48.0). Entrypoint: Home.py (CMD: streamlit run Home.py). Evidence: Home.py, pages/1_Stemwijzer.py, pyproject.toml, Dockerfile
- Database: DuckDB + Ibis (duckdb>=1.3.2, ibis-framework[duckdb]>=10.8.0). Evidence: pyproject.toml, database.py
- ML: scikit-learn, umap-learn, scipy. Evidence: pyproject.toml, pipeline/svd.py, analysis/

## Examples

### pyproject dependencies (evidence: pyproject.toml)
```toml
dependencies = [
    "duckdb>=1.3.2",
    "ibis-framework[duckdb]>=10.8.0",
    "openai>=1.99.7",
    "scipy>=1.11",
    "umap-learn>=0.5",
    "plotly>=5.0",
    "pytest>=9.0.2",
    "requests>=2.32.4",
    "schedule>=1.2.2",
    "streamlit>=1.48.0",
    "scikit-learn>=1.8.0",
    "beautifulsoup4>=4.14.3",
    "lxml>=6.0.2",
]
```

## Anti-patterns / Notes
- pytest is listed under runtime dependencies in pyproject.toml (line: dependencies). Move pytest to dev-dependencies to avoid shipping test runner in production images. Evidence: pyproject.toml
- Many dependencies use permissive ">=" ranges. Recommend pinning or generating lockfile (poetry.lock/requirements.txt) and adding upper bounds for reproducibility.
- openai appears declared but static imports not found; possible unused dependency (evidence: pyproject.toml, ai_provider.py uses requests and environment keys instead of openai).

## Remediations
- Move test-only libs (pytest) to dev-dependencies in pyproject.toml.
- Add lockfile and CI step to check for pinned dependencies.
- Audit declared but unused packages (openai) and remove or confirm dynamic usage.

## Evidence pointers
- pyproject.toml: full dependency list (lines 1-40)
- Home.py: streamlit usage and app entry (file: Home.py) 
- database.py: duckdb table creation and connection (file: database.py lines ~1-350)