The successor of Schleuder v2, aptly named Schleuder v3, has been released. Please see

This website for Schleuder v2 will only continue to exist as reference for people still running the old code. Please use version 3 for any new setups from now on.

Posted 2017-03-07 11:20:22 +0100

The development of schleuder v3 is slow but happening. To release a new version eventually we're looking for people interested in testing a beta-version of schleuder3 and webschleuder3 (the new webinterface!)

You don't have to be an expert to help us. Even if you never used schleuder before you could try the webinterface and tell us what works for you, what doesn't, and which parts you maybe don't understand. Or sending a bunch of emails from your email-client to a schleuder3-list and reporting the findings would also be helpful!

Please contact for details!

Meanwhile version 3.0 of Schleuder has been released:

Posted 2016-02-08 11:07:12 +0100

If you're running Schleuder on Debian and want to dist-upgrade, you'll run into the problem that the outdated dependencies of Schleuder v2 are not available (or even installable) on Debian Jessie. Here's a way we've been told about you still can get Schleuder to work on Debian Jessie:

  1. Before upgrading, make sure you have rubygems1.8 and ruby1.8-dev installed.
  2. Upgrade to Jessie but keep enabled security updates from Wheezy. (Yes, I know.)
  3. Run:

    # gem1.8 install ffi tmail magic # gem1.8 install log4r --version 1.6.13 # gem1.8 install gpgme --version 2.0.2

  4. Edit /usr/bin/schleuder and add, right after the she-bang:

    require 'rubygems' $:.delete('/usr/lib/ruby/vendor_ruby')

We can't promise that this hack won't break anything but we've haven't heard about such downsides. Good luck!

(In case you find this situation awful please consider helping out to push the development of Schleuder v3.)


To make schleuder-newlist work, you apparently have to additionally follow these steps:

  1. Install the 'highline'-gem in a specific version:

     # gem1.8 install highline --version 1.6.21
  2. Edit /usr/bin/schleuder-newlist and add, right after the she-bang:

     require 'rubygems'
Posted 2015-07-27 20:43:29 +0200

Update: For those interested in details, here's code and issues for the next schleuder and the next webschleuder.

We're looking for help to push this project out of its staleness.

To finally get rid of the old libraries and dependencies we started to rewrite Schleuder from scratch.

Unfortunately we're lacking time to carry on in reasonable speed. Therefore we need your help!

There's need to work on

  • the actual Schleuder (Ruby),
  • the new web interface (RubyOnRails, styling and coding),
  • a possible reimplementation of Schleuder in Go (the language),
  • the documentation content,
  • the documentation design.

If you you're having some spare time and feel you might be able to help even a little then we'd love to hear from you!

A motivational peek: The next Schleuder is being built with a database backend and a full featured web interface. Subscription and key management will be easier and more robust for list admins (web and command line) and users, too. All texts will be localized, all keys assinged by fingerprint, no YAML needs to be touched.

To get in contact please email to (receive the OpenPGP public key by sending an email to

Join us!

The current schleuder dev team

Posted 2014-10-28 08:56:30 +0100

Hello world,

although some wondered: schleuder isn't dead. To prove it we've published a new bug-fix-release: version 2.2.4. Most users won't notice a differences, but some a still noteworthy and if you run a server or manage a list you might want to read the changelog.

Those watching more closely might have noticed a new name popping up increasingly: lunar. Since some weeks he's on board as a developer and we're very happy about it!

Bigger changes targeting future releases (e.g. replacing tmail, dropping support for ruby 1.8) are under way. Those will still take a little while though, because we decided to build a test-environment before replacing such a core part of schleuder.

Also another plan slowly grows on the horizon: re-writing webschleuder, schleuder friendly web-frontend. You'll hear from that one hopefully rather sooner than later.

So much for the future. In the present please keep your software up to date and teach your users and friends how important the integrity of all their personal devices is to proctect all participants.

Take care, the schleuder dev team (lunar, ng & paz)

Posted 2013-09-28 17:00:14 +0200

Hello world,

one nasty bug later here's the next version of schleuder: 2.2.3.

This release fixes the recognition of "inline"-signed multipart messages.

No manual intervention is required before or after the upgrade from version 2.2.2.

For downloading options please visit the download-page.

If you have any questions or feedback please do not hesitate to contact us.

Happy hacking, the schleuder dev team (aka ng & paz)

Posted 2012-07-04 14:41:36 +0200

Hello world,

since way too much time we didn't release a new version of schleuder. Originally this release was planned for fall of 2011. But then came life. And bugs, and things. Then, with the freeze for the next version of Debian GNU/Linux approaching we finally managed to get a new version out of the door — and thankfully were immediately flooded by fixes from the maintainer of the debian package, Jérémy Bobbio. So we decided not to make a fuss about the release and instead collected many of his precious fixes and enhancements, added some more of our own, and now are announcing a more valuable version of schleuder2: 2.2.2.

Instead of a dedication here's a big Thank You to Jérémy! You rock!

There have been a lot of changes, too many to list here. If you didn't follow the development please take your time to read the changelog. The ?documentation is up to date, too.

For distribution we finally managed to build a signed rubygem. Installing is now as easy as executing gem install schleuder on any given host running ruby. How to verify the signature is described on the download-page.

git-users can simply git-pull the changes from the master-branch, or checkout (and verify) the tag "schleuder-2.2.2".

If you have any questions or feedback please do not hesitate to contact us.

Happy hacking, the schleuder dev team (aka ng & paz)

Posted 2012-07-01 19:15:34 +0200

TMail Incomapatibility

Beware of the latest tmail release (, it will fail to parse certain attachement types. Schleuder works so far fine with the previous release (

There is actually only a minimal change to with a huge impact. As the latest version is not a severe bugfiy release, we recommend to use instead, as we further inform about tmail compatibility.

Posted 2010-07-08 06:52:29 +0200


We've been asked, what the remailing-capabilities of schleuder are and how they relate to those of mixmaster. As there might be more people out there that have been confused we answer publicly:

Concerning schleuder we use the term "remailing" to refer to the possibility to send out messsages to non-subscribers. Any member (which by the way is the same as a subscriber) can instruct schleuder to not only send the current message to all subscribers, but also to send it to other email addresses specified in the message itself. The idea is, that schleuder can serve as an email-gateway for groups: they can receive emails and also send them out while still staying opaque behind the one email-address driven by schleuder.

This indeed is not the same meaning the word "remailing" has in the mixmaster-context. Maybe we should have called it differently, but then again this word seems to describe the funktionality pretty well. We're sorry if we caused unnecessary confusion.

Posted 2010-02-22 19:46:45 +0100

Just a note we forgot to mention in the changelog for schleuder-2.1.1: The workaround we introduced in 74ec1f16e to also match against the "name"-attribute of user-IDs when looking for email-addresses does not work anymore.

In 68fe3c0f (included in v2.1.1) we restricted the lookup-pattern for email-addresses to avoid false positives (see commit for description), this breaks the aforementioned workaround. As we think this fix is more important than the workaround we take the regression into account.

Sorry if we caused any trouble with this!

Posted 2009-12-30 15:48:22 +0100