diff --git a/lib/lib.nix b/lib/lib.nix
index 3e6005d..e9875c0 100644
--- a/lib/lib.nix
+++ b/lib/lib.nix
@@ -11,7 +11,8 @@
       opts,
       data,
     }: let
-      format = opts.format or "json";
+      _format = opts.format or "json";
+      format = if _format == "yaml" then "yaml_1_2" else _format;
       formatOpts = builtins.removeAttrs opts ["format"];
       formatter = formats.${format} formatOpts;
 
@@ -22,7 +23,7 @@
           lua = "--- Generated by soonix, DO NOT EDIT\n";
           xml = "<!-- Generated by soonix, DO NOT EDIT -->\n";
         }.${
-          format
+          _format
         } or "";
     in
       (formatter.generate name data).overrideAttrs (pre: {