emacs.d/bundle/bundle--email.el

(when (eq system-type 'gnu/linux)
  (use-package mu4e
    :ensure nil
    :custom
    (mu4e-change-filenames-when-moving t)
    (mu4e-drafts-folder "/Drafts")
    (mu4e-get-mail-command "mbsync -a")
    (mu4e-headers-date-format "%Y-%m-%d %H:%M")
    (mu4e-refile-folder "/Archive")
    (mu4e-sent-folder "/Sent")
    (mu4e-trash-folder "/Trash")
    (mu4e-split-view 'horizontal)
    (mu4e-compose-signature "Cheers Marcus (Nuremberg . Germany)\nGnuPG Key: https://meta.sr.ht/~marcuskammer.pgp\nFingerprint: 86DB 0F30 F9F1 661A 54E2 1664 C374 817B E285 268F")
    (mu4e-update-interval (* 10 60))
    (mu4e-headers-unread-mark    '("u" . "📩 "))
    (mu4e-headers-draft-mark     '("D" . "🚧 "))
    (mu4e-headers-flagged-mark   '("F" . "🚩 "))
    (mu4e-headers-new-mark       '("N" . "✨ "))
    (mu4e-headers-passed-mark    '("P" . "↪ "))
    (mu4e-headers-replied-mark   '("R" . "↩ "))
    (mu4e-headers-seen-mark      '("S" . " "))
    (mu4e-headers-trashed-mark   '("T" . "🗑️"))
    (mu4e-headers-attach-mark    '("a" . "📎 "))
    (mu4e-headers-encrypted-mark '("x" . "🔑 "))
    (mu4e-headers-signed-mark    '("s" . "🖊 ")))

  (use-package smtpmail
    :ensure nil
    :defer t
    :custom
    (message-send-mail-function 'smtpmail-send-it)
    (smtpmail-smtp-server "smtp.mailbox.org")
    (smtpmail-smtp-service 465)
    (smtpmail-stream-type 'tls)
    (message-send-mail-function 'smtpmail-send-it)
    (smtpmail-auth-credentials (expand-file-name "~/.authinfo.gpg")))

  ;; (setq mml-secure-openpgp-signers '("86DB0F30F9F1661A54E21664C374817BE285268F"))
  ;; (add-hook 'message-send-hook 'mml-secure-message-sign-pgpmime)

  (defun mk/sign-email ()
    ;; Sign an Email using the key of the sender.
    (interactive)
    (setq mml-secure-openpgp-sign-with-sender t)
    (mml-secure-message-sign-pgp))

  (defun mk/encrypt-email ()
    ;; Encrypt an Email using the key of the recipient.
    (interactive)
    (mml-secure-message-encrypt-pgp)))