On Fri, Jul 09, 2021 at 01:26:30PM +0300, Andrew Tropin wrote:
> From 38987bffcd1088315c6414d6c6141140c3969e6b Mon Sep 17 00:00:00 2001
> From: Andrew Tropin <andrew@trop.in>
> Date: Fri, 9 Jul 2021 13:20:10 +0300
> Subject: [PATCH] gnu: msmtp: Make it configurable with envrinoment variables
> 
> Add the support of following environment variables:
> MSMTPQ_QUEUE_DIR
> MSMTPQ_LOG
> MSMTPQ_QUIET
> MSMTPQ_CONN_TEST
> 
> Add new --enqueue option, which forces to enqueue message instead of
> attempting to send it.
> 
> Make msmtpq quite by default for compatibility with emacs and use ping instead
> of netcat for connection test.
> 
> Use binary absolute path in msmtpq and msmtp-queue scripts instead of relying
> on the binary being present in the $PATH.

Thanks!

Did you send these patches upstream?

https://marlam.de/msmtp/contact/

In general, we don't patch packages to add features in Guix. We try to
stay close to what is offered by the upstream development team, except
for bug fixes.