It's unlikely that conventional email will be wanted on a mesh, but not totally infeasible

i.e. the transport mechanism could be p2p

src/freedombone-image-mesh

@@ -124,6 +124,7 @@ function set_hostname {
     DEFAULT_DOMAIN_NAME="$1"
 
     echo "$DEFAULT_DOMAIN_NAME" > /etc/hostname
+    echo "$DEFAULT_DOMAIN_NAME" > /etc/mailname
     hostname $DEFAULT_DOMAIN_NAME
 
     if grep -q "127.0.1.1" /etc/hosts; then