diff --git a/schala-repl/src/language.rs b/schala-repl/src/language.rs
index d3e552f..29c04ff 100644
--- a/schala-repl/src/language.rs
+++ b/schala-repl/src/language.rs
@@ -217,8 +217,8 @@ macro_rules! pass_chain_helper {
       }
       match output {
         Ok(result) => pass_chain_helper! { ($state, $comp, $eval_options); result $(, $rest)* },
-        Err(err) => {
-          $comp.output(Err(format!("Pass {} failed with {:?}", pass_name, err)))
+        Err(err) => { //TODO this error type needs to be guaranteed to provide a useable string
+          $comp.output(Err(format!("Pass {} failed:\n{}", pass_name, err)))
         }
       }
     }