Virtual Environments and Project Management

venv, pip freeze, requirements.txt, and managing dependencies professionally.

Why Virtual Environments?

Different projects often need different package versions. A virtual environment creates an isolated Python installation per project, preventing conflicts.

Creating a Virtual Environment

In Visual Studio 2026, right-click Python Environments in Solution Explorer → Add Environment. Or from the terminal:

# Create
python -m venv .venv

# Activate (Windows)
.venv\Scripts\activate

# Activate (macOS / Linux)
source .venv/bin/activate

# Deactivate
deactivate

Managing Dependencies

pip install requests pandas           # install
pip install requests==2.31.0          # specific version
pip freeze > requirements.txt         # snapshot
pip install -r requirements.txt       # restore on another machine
pip list                               # what's installed
pip show pandas                        # details about a package
pip uninstall requests                 # remove

Project Structure Best Practices

my_project/
├── .venv/               # virtual environment (not in git)
├── src/
│   ├── __init__.py
│   └── main.py
├── tests/
│   └── test_main.py
├── requirements.txt
└── README.md