NeoMutt uses zstd compression in its email cache.
(since release 2020-03-20)
- https://neomutt.org/feature/hccompress
<li><a href="https://code.facebook.com/projects/470946523057396/mcrouter/"><img src="images/mcrouter.png"/></a> [mcrouter](https://github.com/facebook/mcrouter/blob/master/mcrouter/lib/ZstdCompressionCodec.h) </li>
<li><a href="https://rspamd.com/" ><img src="images/rspamd.png" /></a> [Rspamd](https://rspamd.com/announce/2016/11/21/rspamd-1.4.0.html) </li>
<li><a href="https://www.torproject.org/" ><img src="images/tor.png" /></a> [Tor](https://blog.torproject.org/blog/tor-0312-alpha-out-notes-about-0311-alpha) </li>
+ <li><a href="https://neomutt.org/" ><img src="images/neomutt.png" /></a> [NeoMutt](https://neomutt.org/feature/hccompress) </li>
</ul>
</div>