Optional and Development Dependencies

What this Python packaging interview question tests

This is a medium-difficulty question about Python project configuration and dependency management. It probes whether you understand the distinction between runtime dependencies and development-time tooling, and how modern Python packaging conventions encode that distinction.

Candidates are expected to be familiar with pyproject.toml as the standard configuration file for Python projects, and to know how to structure dependencies so that end users installing the package pay no cost for testing frameworks, linters, or other contributor tools. The question rewards knowledge of both the mechanism and the reasoning behind it.

• Dependency groups and optional dependencies in pyproject.toml
• The role of development, testing, and maintenance toolchains
• Package installation modes: normal vs. editable installs
• Dependency isolation and lightweight distribution