diff --git a/machines/renge/services/matrix/synapse.nix b/machines/renge/services/matrix/synapse.nix
index 19d7c29..8c63337 100644
--- a/machines/renge/services/matrix/synapse.nix
+++ b/machines/renge/services/matrix/synapse.nix
@@ -78,6 +78,9 @@ in
 
       # I’m okay with using matrix.org as trusted key server
       suppress_key_server_warning = true;
+
+      # For mautrix-whatsapp backfilling
+      experimental_features.msc2716_enabled = true;
     };
 
     extraConfigFiles = with config.sops.secrets; [