I've been using Python for about 6 years, my last company wrote it's core commercial product exclusively in python. I've never used venvs, but I've yet to run

I've been using Python for about 6 years, my last company wrote it's core commercial product exclusively in python. I've never used venvs, but I've yet to run into a situation where virtualenv (maybe with virtualwrappers as sugar), and pip + requirements.txt haven't been able to handle even fairly complex install situations.