Hi, I would like to have a local PyPI mirror to be able to deploy python software even if PyPI is down. My deployment process is the ordinary git checkout + pip install -r requirements.txt. I found devpi and it looks like it would do what I want, if I believe the feature listed very first on the homepage: "After files are first requested can work off-line and will try to re-check with pypi every 30 minutes by default" (even though I'm not quite sure why it needs to "recheck" anything) However, I installed it and tried to make it work, but I didn't find that it offers the resilience I seek. What I did is use the default index that mirrors PyPI. I installed a package through devpi, then simulated PyPI being down, and tried to install the package again, and it worked well, devpi served the package itself. However, I then saw in the documentation something about packages being cached for 30 minutes. So I waited 30 minutes, tried again, and indeed then nothing worked, devpi (according to its logfile) tried contacting PyPI again and again, and at the end failed to serve the file to pip. I thought that maybe it would make a difference if I used pip install with or without a version number, assuming that without a version number, devpi wants to contact PyPI to retrieve the latest version, but with a version number, it would be able to figure that it already has it locally... But no, version number or not in the pip command line, it fails. My instinct is that I don't want to cache packages for a mere 30 minutes. I want a mirror. Once a package has been downloaded once, I want it to stay in the mirror forever. I don't understand why I would want it to expire. Am I missing something? Should I set the mirror_cache_expiry to MAX_INT? Can devpi not do what I want? Am I wrong in wanting what I want? Thanks a lot for your help :)