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This is a PyPI mirror client according to PEP 381.

Build status

Packaging and PIP install


The following instructions will place the bandersnatch executable in a virtualenv under bandersnatch/bin/bandersnatch.


bandersnatch requires Python 3.5


This installs the latest stable, released version.

$ virtualenv --python=python3.5 bandersnatch
$ cd bandersnatch
$ bin/pip install -r https://bitbucket.org/pypa/bandersnatch/raw/stable/requirements.txt


This installs the current development version. Use 'hg up <version>' and run buildout again to choose a specific release.

$ hg clone https://bitbucket.org/pypa/bandersnatch
$ cd bandersnatch
$ ./bootstrap.sh


  • Run bandersnatch mirror - it will create an empty configuration file for you in /etc/bandersnatch.conf.
  • Review /etc/bandersnatch.conf and adapt to your needs.
  • Run bandersnatch mirror again. It will populate your mirror with the current status of all PyPI packages - roughly 500GiB (2017-02-12). Expect this to grow substantially over time.
  • Run bandersnatch mirror regularly to update your mirror with any intermediate changes.


Configure your webserver to serve the web/ sub-directory of the mirror. For nginx it should look something like this:

server {
    server_name <mymirrorname>;
    root <path-to-mirror>/web;
    autoindex on;
    charset utf-8;
  • Note that it is a good idea to have your webserver publish the HTML index files correctly with UTF-8 as the carset. The index pages will work without it but if humans look at the pages the characters will end up looking funny.
  • Make sure that the webserver uses UTF-8 to look up unicode path names. nginx gets this right by default - not sure about others.

Cron jobs

You need to set up one cron job to run the mirror itself.

Here's a sample that you could place in /etc/cron.d/bandersnatch:

*/2 * * * * root bandersnatch mirror |& logger -t bandersnatch[mirror]

This assumes that you have a logger utility installed that will convert the output of the commands to syslog entries.


bandersnatch does not keep much local state in addition to the mirrored data. In general you can just keep rerunning bandersnatch mirror to make it fix errors.

If you delete the state files then the next run will force it to check everything against the master PyPI:

* delete ``./state`` file and ``./todo`` if they exist in your mirror directory
* run ``bandersnatch`` mirror to get a full sync

Be aware, that full syncs likely take hours depending on PyPIs performance and your network latency and bandwidth.

Operational notes

Case-sensitive filesystem needed

You need to run bandersnatch on a case-sensitive filesystem.

OS X natively does this OK even though the filesystem is not strictly case-sensitive and bandersnatch will work fine when running on OS X. However, tarring a bandersnatch data directory and moving it to, e.g. Linux with a case-sensitive filesystem will lead to inconsistencies. You can fix those by deleting the status files and have bandersnatch run a full check on your data.

Many sub-directories needed

The PyPI has a quite extensive list of packages that we need to maintain in a flat directory. Filesystems with small limits on the number of sub-directories per directory can run into a problem like this:

2013-07-09 16:11:33,331 ERROR: Error syncing package: zweb@802449
OSError: [Errno 31] Too many links: '../pypi/web/simple/zweb'

Specifically we recommend to avoid using ext3. Ext4 and newer does not have the limitation of 32k sub-directories.

Client Compatibility

A bandersnatch static mirror is compatible only to the "static", cacheable parts of PyPI that are needed to support package installation. It does not support more dynamic APIs of PyPI that maybe be used by various clients for other purposes.

An example of an unsupported API is PyPI's XML-RPC interface, which is used when running pip search.


If you have questions or comments, please submit a bug report to http://bitbucket.org/pypa/bandersnatch/issues/new.

Code of Conduct

Everyone interacting in the bandersnatch project's codebases, issue trackers, chat rooms, and mailing lists is expected to follow the PyPA Code of Conduct.


This client is based on the original pep381client by Martin v. Loewis.

Richard Jones was very patient answering questions at PyCon 2013 and made the protocol more reliable by implementing some PyPI enhancements.