(Disclosure: I am the author of that package)
* [astroid](https://github.com/astroidmail/astroid), a graphical threads-with-tags mail user agent for notmuch. Written in C++ using GTK+, WebKit and gmime.
* [bower](https://github.com/wangp/bower), a curses frontend written in [Mercury](http://www.cs.mu.oz.au/research/mercury/).
* [neomutt](https://www.neomutt.org/feature/notmuch), a fork of [mutt](http://www.mutt.org/) able to use Notmuch for virtual folders.
* [astroid](https://github.com/astroidmail/astroid), a graphical threads-with-tags mail user agent for notmuch. Written in C++ using GTK+, WebKit and gmime.
* [bower](https://github.com/wangp/bower), a curses frontend written in [Mercury](http://www.cs.mu.oz.au/research/mercury/).
* [neomutt](https://www.neomutt.org/feature/notmuch), a fork of [mutt](http://www.mutt.org/) able to use Notmuch for virtual folders.
+* [netviel](https://github.com/DavidMStraub/netviel), a single-page web app with Javascript frontend and Python backend.
* [noservice](https://gitlab.com/noservice/noservice). Web interface, written in Clojure.
* [notmuchfs](https://github.com/tsto/notmuchfs), a virtual maildir file system for Notmuch queries.
* [noservice](https://gitlab.com/noservice/noservice). Web interface, written in Clojure.
* [notmuchfs](https://github.com/tsto/notmuchfs), a virtual maildir file system for Notmuch queries.