Make requires tabs (at least a leading tab).

Anything but an all-spaces practice will make you miserable in Python.

But in practice, in any environment where I've worked, there's never been a problem with mixed tabs and spaces for most languages. I've only ever seen this debate online, never in the office.

Tabs align at boundaries of 8 spaces by default in all environments in which I've worked. (Tab characters, that is. I'm not talking about what an editor might insert when you hit the tab key.) Are there any significant environments where this is not true?