The author mentions PEP 8. In the Python community, there is a style checker called pep8, which implements the PEP 8 guidelines. Style only. There's also a tool called pyflakes, which does static code analysis. Obviously, it can't catch much, but it does alright. Then, there are lints: pylint and pychecker. These last two are horribly dogmatic and cannot stand Python which isn't written in their style. We usually don't recommend pylint and pychecker because of their overbearing nature and insistence on Java-in-Python code.

I recently built a couple websites, and we used Sass for the CSS, so we ended up with very nicely formatted SCSS maintained by hand, and minified CSS for deployment. I tried CSS Lint and was horrified at what it did to our CSS, so it's no longer part of our cycle.

If people wanna use it, fine, but it's not helpful to me.