> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pyx.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Mirroring vs. proxying

pyx includes two modes for serving packages from public sources, like PyPI and
the PyTorch index: mirroring and proxying.

You can enable or disable the mirror in the
[Settings tab](https://app.pyx.dev/team/settings).

## Mirroring

When the mirror is enabled, pyx will serve packages from its own CDN,
replicating packages from PyPI (or another public index) continuously and in
real-time, and serving them from the same infrastructure as is used for private
package delivery.

Concretely, when the mirror is enabled, PyPI packages will be served from
`https://files.astralhosted.com`, rather than `https://files.pythonhosted.org`.

<Note>
  When using [static IPs](/static-ips), files will be served from
  `https://files-static.astralhosted.com`.
</Note>

## Proxying

When the proxy is enabled, pyx will serve packages from the public source
directly, without any additional replication or caching.

Concretely, when the proxy is enabled, PyPI packages will be served from
`https://files.pythonhosted.org`, rather than `https://files.astralhosted.com`.

<Note>
  When using [static IPs](/static-ips), public packages will still be served
  from the public source directly, and not pyx's static IPs.
</Note>

## Choosing a delivery mode

When the mirror is enabled, pyx can serve its own optimized artifacts to the uv
client, enabling faster installation times. For example, the PyTorch wheels
served by the mirror are up to 40% smaller than those served by
`https://download.pytorch.org`.

Enabling the mirror also reduces your points of failure, as all downloads are
served from pyx's infrastructure, creating resilience against outages at the
public source. Downloads through the mirror will also be tracked in the pyx
dashboard, enabling monitoring of package download counts and other team-wide
analytics.

Importantly, though, downloads through the mirror count towards your team's
bandwidth usage, while downloads from the proxy do not. As such, the proxy can
be a better choice for teams looking to minimize bandwidth usage and focus their
pyx usage on private package hosting.

Regardless of which mode is enabled, the pyx API endpoints remain unchanged
(e.g., `https://api.pyx.dev/simple/pypi` for PyPI, or
`https://api.pyx.dev/simple/acme/main` for your team's private index); custom
views are also supported in both modes.

## Toggling delivery modes

You can enable or disable the mirror in the
[Settings tab](https://app.pyx.dev/team/settings).

After enabling or disabling the mirror, refresh your access token
(`uv auth token pyx.dev`) in the uv client for the changes to take immediate
effect, and refresh your lockfile (`uv lock --refresh`) to replace the cached
file URLs without modifying the selected versions.