Hi,

I played around with the lei interface for a bit, and I have some
thoughts and observations:

* I noticed that ‘piem-lei-query’ was a little slow, at least compared
  to notmuch.el.  I have indexed the guix-devel and guix-patches mailing
  lists (I think) and making the query ‘d:20.days.ago.. guix’ took
  around three seconds.  It seems like it waits for all the results from
  lei to arrive before processing them, whereas notmuch.el processes the
  messages as they come, similar to ‘git log’.

* I like how the interface resembles the Web interface, especially the
  threaded view.

* In PGP singed messages there is a ‘lei blob OID’ attachment, not sure
  why that is there

  --8<---------------cut here---------------start------------->8---
  # kw:seen
  From: Maxime Devos <maximedevos@telenet.be>
  To: David Dashyan <mail@davie.li>, Guix Help <help-guix@gnu.org>
  Subject: Re: Bug? Importing (gnu rest ...) fails due to lack of patch files on build side.
  Date: Sun, 25 Apr 2021 18:24:57 +0200
  Message-ID: <f2aa26f2fba3e080bd528c0ab10ebb121483aac4.camel@telenet.be>
  In-Reply-To: <87blajj0kh.fsf@davie.li>
  
  [-- Attachment #1: Type: text/plain; charset="UTF-8", Size: 5599 bytes --]
  [-- lei blob 69667b191433ea4c4a46dd8414a4c5ee366d8e4d:1 --]
  
  [...]
  --8<---------------cut here---------------end--------------->8---

  and at the end of the message

  --8<---------------cut here---------------start------------->8---
  Greetings,
  Maxime
  [-- Attachment #2: This is a digitally signed message part --]
  [-- Type: application/pgp-signature; name="signature.asc", Size: 260 bytes --]
  [-- lei blob 69667b191433ea4c4a46dd8414a4c5ee366d8e4d:2 --]
  --8<---------------cut here---------------end--------------->8---

* One slight annoyance is that pressing {q} in the ‘lei-query’ buffer
  just hides the buffer itself, so I end up with two windows, one with a
  ‘lei-show’ buffer and another one with some random buffer I happen
  to have open before I invoked ‘piem-lei-query’.  In notmuch.el,
  pressing {q} in the ‘notmuch-tree’ buffer first hides the
  corresponding ‘notmuch-show’ window.

Some questions that poped into my mind:

* I quite like the ‘notmuch-tree’ view, would it make sense to have
  something similar if piem so one could display multiple threads in one
  buffer, instead of just display a single thread (unless I haved missed
  something) like ‘piem-lei-query-thread’?

* Since piem is not an MUA, will there be any support for sending
  messages, or will users be expected to use {M-x compose-mail} or
  something?

Those are some thing I had in mind, sorry if the message got a bit long
:)  I don’t know if I will be able to send patches, but I really like
what I am seeing so far, thank you for the work!