What is the meaning of “Failed building wheel for X” in pip install?

Question

This is a truly popular question here at SO, but none of the many answers I have looked at, clearly explain what this error really mean, and why it occurs.

One sour

Answer 1

It might be helpful to address this question from a package deployment perspective.

There are many tutorials out there that explain how to publish a package to PyPi. Below are a couple I have used;

medium
real python

My experience is that most of these tutorials only have you use the .tar of the source, not a wheel. Thus, when installing packages created using these tutorials, I've received the "Failed to build wheel" error.

I later found the link on PyPi to the Python Software Foundation's docs PSF Docs. I discovered that their setup and build process is slightly different, and does indeed included building a wheel file.

After using the officially documented method, I no longer received the error when installing my packages.

So, the error might simply be a matter of how the developer packaged and deployed the project. None of us were born knowing how to use PyPi, and if they happened upon the wrong tutorial -- well, you can fill in the blanks.

I'm sure that is not the only reason for the error, but I'm willing to bet that is a major reason for it.