Dear subscribers of kwant-devel and of kwant-discuss,
Due to the very limited usage of the kwant-devel mailing list (most development discussions happen in the issues and merge requests of our gitlab instance ), we have decided to retire it.
Still, a mailing list is a useful forum also for development, especially when more general topics are being discussed. That's why, starting from now, we recommend  the use the kwant-discuss list also for development discussions. This will have the welcome side-effect of giving development discussions a wider audience. Note that kwant-discuss was never meant to be a pure Q&A list.
A number of subscribers to kwant-devel are not members of kwant-discuss. Would you please consider subscribing? The average volume is rather low: a couple of messages per week. In order to subscribe, simply send an arbitrary message to firstname.lastname@example.org (the subject and body are ignored).
(Those who are subscribed to both lists have received this message twice. My apologies for that.)
As far as kwant-devel is concerned, you have nothing to do. Posting is technically still allowed for the time being. We will eventually disable it, but the list and its archives will continue to linger.