ssl_session_cache shared:SSL:50m;
ssl_session_timeout 1440m;
ssl_session_tickets off;

ssl_protocols TLSv1.2 TLSv1.3;
ssl_prefer_server_ciphers on;
ssl_ciphers ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305;
ssl_ecdh_curve X25519:X448:secp384r1:secp256k1;

ssl_stapling on;
ssl_stapling_verify on;
resolver 127.0.0.1:53 '[::1]:53' 1.1.1.1:53 1.0.0.1:53 '[2606:4700:4700::1111]:53' '[2606:4700:4700::1001]:53' valid=300s;
resolver_timeout 30s;

# Not needed normally as mailcow has this already set.
#add_header Strict-Transport-Security "max-age=31536000";