diff --git a/overlays/testing.nix b/overlays/testing.nix
index b43344c6..dbda31f7 100644
--- a/overlays/testing.nix
+++ b/overlays/testing.nix
@@ -18,7 +18,7 @@ let
               say [i|### Build failure for ${name} config for #{hostname} ###|]
               cat logFile
         say [i|Trying to build ${name} config for #{hostname}. Logging to #{logFile}.|]
-        onException command
+        onException command failHandler
       say [i|Build of ${name} config for #{hostname} was successful.|]
   '';
 in {
@@ -27,17 +27,13 @@ in {
     name = "test-system-config";
     inherit bins;
     inherit imports;
-  } (haskellBody "system" ''
-    nix_build $ ["<nixpkgs/nixos>", "-A", "system"] ++ paths ++ ["-I", [i|nixos-config=#{configDir}/hosts/#{hostname}/configuration.nix|], "-o", [i|result-system-#{hostname}|]] ++ fmap toString args
-  '');
+  } (haskellBody "system" ''nix_build $ ["<nixpkgs/nixos>", "-A", "system"] ++ paths ++ ["-I", [i|nixos-config=#{configDir}/hosts/#{hostname}/configuration.nix|], "-o", [i|result-system-#{hostname}|]] ++ fmap toString args'');
 
   test-home-config = self.writeHaskellScript {
     name = "test-home-config";
     inherit bins;
     inherit imports;
-  } (haskellBody "home" ''
-    nix_build $ paths ++ [[i|#{configDir}/home/target.nix|], "-A", hostname, "-o", [i|result-home-manager-#{hostname}|]] ++ fmap toString args
-  '');
+  } (haskellBody "home" ''nix_build $ paths ++ [[i|#{configDir}/home/target.nix|], "-A", hostname, "-o", [i|result-home-manager-#{hostname}|]] ++ fmap toString args'');
 
   test-config = self.writeHaskellScript {
     name = "test-config";