diff --git a/maintainers/scripts/update.py b/maintainers/scripts/update.py
index 10d197d5fe78..ca35f04d1285 100644
--- a/maintainers/scripts/update.py
+++ b/maintainers/scripts/update.py
@@ -92,7 +92,15 @@ async def attr_instantiation_worker(
 ) -> tuple[Path, str]:
     async with semaphore:
         eprint(f"Instantiating {attr_path}…")
-        return (await nix_instantiate(attr_path), attr_path)
+        try:
+            return (await nix_instantiate(attr_path), attr_path)
+        except Exception as e:
+            # Failure should normally terminate the script but
+            # looks like Python is buggy so we need to do it ourselves.
+            eprint(f"Failed to instantiate {attr_path}")
+            if e.stderr:
+                eprint(e.stderr.decode("utf-8"))
+            sys.exit(1)
 
 
 async def requisites_worker(