don't allow gmail addresses to subscribe

srv/src/http/mailinglist.go

@@ -18,6 +18,10 @@ func (a *api) mailingListSubscribeHandler() http.Handler {
 			len(email) >= 512 {
 			apiutil.BadRequest(rw, r, errors.New("invalid email"))
 			return
+
+		} else if strings.ToLower(parts[1]) == "gmail.com" {
+			apiutil.BadRequest(rw, r, errors.New("gmail does not allow its users to receive email from me, sorry"))
+			return
 		}
 
 		err := a.params.MailingList.BeginSubscription(email)

srv/src/http/tpl/follow.html

@@ -42,6 +42,12 @@
   complete the process if you don't immediately see anything in your inbox.
 </p>
 
+<p style="color: red;">
+  Unfortunately Google considers all emails from my mail server to be spam. I'm
+  tired of seeing the bounce errors on my side, so I'm disabling the ability to
+  sign up for the mailing list with a GMail address. Sorry (not sorry).
+</p>
+
 <style>
 
 #emailStatus.success {