diff --git a/modules/servers/synapse.nix b/modules/servers/synapse.nix
index 3539033..1fa4e44 100644
--- a/modules/servers/synapse.nix
+++ b/modules/servers/synapse.nix
@@ -71,6 +71,7 @@ in
           federation_domain_whitelist = [ ];
           allow_public_rooms_without_auth = false;
           allow_public_rooms_over_federation = false;
+          registration_shared_secret = config.sops.secrets.synapse.path;
           max_upload_size = "4096M";
           tls_private_key_path = config.sops.secrets."matrix/key".path;
           tls_certificate_path = config.sops.secrets."matrix/cert".path;