&gt; The problem comes when you rely on adding packages that just talk directly to your framework (like Django middleware). Once you do that a few times, you really don&#x27;t know what&#x27;s going on between a web request hitting your server, and your own code running<p>I think this is where the lack of strict typing can make things harder to figure out. Especially if you&#x27;re trying to understand middleware functions with opaque signatures (like <i></i>kwargs in Python). IDEs like PyCharm do their best at providing &quot;Find all references&quot;, &quot;Go to defintion&quot; etc, and that helps, but it&#x27;s not quite the same. Putting the info in the docstring is better than nothing, but it&#x27;s still harder to parse (and maybe not machine parseable) and who knows if it&#x27;s really correct?<p>Personally I&#x27;m really hoping mypy or type-hinting really takes off in Python 3, and makes everyone&#x27;s life easier.