May, 05 2025

While deploying a Python application on a production server, I ran into a uncommon issue (at least for me):

the server had no internet access due to security policies, yet the application required external Python packages.

This excluded the standard pip install workflow and required a different approach.

Python’s .whl format (wheel) is a binary distribution format defined in PEP 427. It allows pip to install packages without building from source, which is useful when a compiler toolchain isn’t available or when dealing with offline environments.

The flow is simple: first download the .whl files on a machine with internet access (with pip download), then transfer them to the offline server, and finally install them using pip (pip install --no-index --find-links=..).