diff --git a/rswag-api/lib/rswag/api/middleware.rb b/rswag-api/lib/rswag/api/middleware.rb
index c1a4fbb..7256794 100644
--- a/rswag-api/lib/rswag/api/middleware.rb
+++ b/rswag-api/lib/rswag/api/middleware.rb
@@ -31,7 +31,7 @@ module Rswag
       private
 
       def parse_file(filename)
-        if /\.yml$/ === filename
+        if /\.ya?ml$/ === filename
           load_yaml(filename)
         else
           load_json(filename)