* ~send-email~ with ~.authinfo.gpg~
** Step 1: Install ~git-credential-netrc~
AFAICT not all distributions package this script?  As far as those I
use are concerned:

- On Debian, the =git= package brings
  =/usr/share/doc/git/contrib/credential/netrc/git-credential-netrc.perl=,
  but the file is not executable, so it's not as simple as symlinking
  it from =~/.local/bin=: it must be =cp='ed and =chmod='ed.

- openSUSE does not include anything from =contrib=, I think?  So just
  grab =contrib/credential/netrc/git-credential-netrc.perl= from the [[https://git.kernel.org/pub/scm/git/git.git/][Git
  repository]], stick it in =~/.local/bin= and =chmod= it.

Now ~git help --all | grep credential-~ should show =credential-netrc=.

** Step 2: Configure ~git send-email~
In =~/.gitconfig=, assuming a GMail account for =luser@gmail.com=:

#+begin_src conf
[sendemail]
        smtpencryption = tls
        smtpserver = smtp.gmail.com
        smtpuser = luser
        smtpserverport = 587
#+end_src

Most =send-email= guides seem to use the full email address for
=smtpuser=; I'm putting in just the /local-part/, since that's what is in
my =~/.authinfo.gpg=.

** Step 3: Configure ~git-credential~
In =~/.gitconfig=:

#+begin_src conf
[credential]
        helper = netrc
#+end_src

** Step 4: Enjoy 📨