diff --git a/lib/synvert/core/exceptions.rb b/lib/synvert/core/exceptions.rb
index e683d8c6..8e1867f6 100644
--- a/lib/synvert/core/exceptions.rb
+++ b/lib/synvert/core/exceptions.rb
@@ -2,14 +2,14 @@
 
 module Synvert::Core
   # Rewriter not found exception.
-  class RewriterNotFound < Exception
+  class RewriterNotFound < RuntimeError
   end
 
   # Gemfile.lock not found exception.
-  class GemfileLockNotFound < Exception
+  class GemfileLockNotFound < RuntimeError
   end
 
   # Method not supported exception.
-  class MethodNotSupported < Exception
+  class MethodNotSupported < RuntimeError
   end
 end