diff --git a/tvix/eval/src/builtins/mod.rs b/tvix/eval/src/builtins/mod.rs
index 6723b8d62..699dbf74c 100644
--- a/tvix/eval/src/builtins/mod.rs
+++ b/tvix/eval/src/builtins/mod.rs
@@ -311,7 +311,9 @@ mod pure_builtins {
         if is_path {
             Ok(Value::Path(Box::new(result.into())))
         } else {
-            Ok(result.into())
+            Ok(Value::String(NixString::new_inherit_context_from(
+                &str, result,
+            )))
         }
     }