Project environments and packages

The single most important habit: one isolated environment per project.

Python options

• venv + pip — built-in, simple, universal
• uv — fast, modern, recommended default
• pipenv — modern, handles both env and packages
• conda / mamba — best when you need non-Python binaries (GDAL, CUDA, etc.)
• poetry, pdm — alternatives worth knowing

R

• renv for project-scoped package libraries
• CRAN vs. Posit Package Manager vs. GitHub installs

Reproducibility checklist

• A lockfile is committed (uv.lock, requirements.txt, renv.lock)
• The README states the language version
• A new clone can run one command to get a working environment