diff --git a/nixos/modules/services/databases/foundationdb.nix b/nixos/modules/services/databases/foundationdb.nix
index 169ed37b348e..490c5e9d005a 100644
--- a/nixos/modules/services/databases/foundationdb.nix
+++ b/nixos/modules/services/databases/foundationdb.nix
@@ -35,7 +35,10 @@ let
     ${optionalString (cfg.class != null) "class = ${cfg.class}"}
     memory         = ${cfg.memory}
     storage_memory = ${cfg.storageMemory}
+
+    ${optionalString (lib.versionAtLeast cfg.package.version "6.1") ''
     trace_format   = ${cfg.traceFormat}
+    ''}
 
     ${optionalString (cfg.tls != null) ''
       tls_plugin           = ${pkg}/libexec/plugins/FDBLibTLS.so
@@ -327,6 +330,15 @@ in
   };
 
   config = mkIf cfg.enable {
+    assertions = [
+      { assertion = lib.versionOlder cfg.package.version "6.1" -> cfg.traceFormat == "xml";
+        message = ''
+          Versions of FoundationDB before 6.1 do not support configurable trace formats (only XML is supported).
+          This option has no effect for version '' + cfg.package.version + '', and enabling it is an error.
+        '';
+      }
+    ];
+
     environment.systemPackages = [ pkg ];
 
     users.users = optionalAttrs (cfg.user == "foundationdb") (singleton