Skip to main content

Waitress WSGI server

Project description

latest version of waitress on PyPI master Documentation Status IRC Freenode

Waitress is a production-quality pure-Python WSGI server with very acceptable performance. It has no dependencies except ones which live in the Python standard library. It runs on CPython on Unix and Windows under Python 3.6+. It is also known to run on PyPy (version 3.6 compatible) on UNIX. It supports HTTP/1.0 and HTTP/1.1.

For more information, see the “docs” directory of the Waitress package or visit

2.0.0 (2021-03-07)

Friendly Reminder

This release still contains a variety of deprecation notices about defaults that can be set for a variety of options.

Please note that this is your last warning, and you should update your configuration if you do NOT want to use the new defaults.

See the arguments documentation page for all supported options, and pay attention to the warnings:

Without further ado, here’s a short list of great changes thanks to our contributors!


  • Fix a crash on startup when listening to multiple interfaces. See

  • Waitress no longer attempts to guess at what the server_name should be for a listen socket, instead it always use a new adjustment/argument named server_name.

    Please see the documentation for server_name in and see

  • Allow tasks to notice if the client disconnected.

    This inserts a callable waitress.client_disconnected into the environment that allows the task to check if the client disconnected while waiting for the response at strategic points in the execution and to cancel the operation.

    It requires setting the new adjustment channel_request_lookahead to a value larger than 0, which continues to read requests from a channel even if a request is already being processed on that channel, up to the given count, since a client disconnect is detected by reading from a readable socket and receiving an empty result.


  • Drop Python 2.7 and 3.5 support

  • The server now issues warning output when it there are enough open connections (controlled by “connection_limit”), that it is no longer accepting new connections. This situation was previously difficult to diagnose. See

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for waitress, version 2.0.0
Filename, size File type Python version Upload date Hashes
Filename, size waitress-2.0.0-py3-none-any.whl (56.5 kB) File type Wheel Python version py3 Upload date Hashes View
Filename, size waitress-2.0.0.tar.gz (175.6 kB) File type Source Python version None Upload date Hashes View

Supported by

AWS AWS Cloud computing Datadog Datadog Monitoring DigiCert DigiCert EV certificate Facebook / Instagram Facebook / Instagram PSF Sponsor Fastly Fastly CDN Google Google Object Storage and Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Salesforce Salesforce PSF Sponsor Sentry Sentry Error logging StatusPage StatusPage Status page