[conradev]

I'm surprised that no one has mentioned pip-tools: https://github.com/nvie/pip-tools

It's a very similar set of tools. I use pip-compile which allows me to put all of my dependencies into a `requirements.in` file, and then "compile" them to a `requirements.txt` file as a lockfile (so that it is compatible with pip as currently exists).

This looks great, though, I'm excited to check it out!

[FabioFleitas]

We use pip-tools on all our Python projects and it works great. I believe the requirements.in compiled to requirements.txt approach is much more sane and less error-prone.