diff --git a/flake.nix b/flake.nix
index 8a6debe..55c927d 100644
--- a/flake.nix
+++ b/flake.nix
@@ -45,6 +45,8 @@
         env = {
           CC = "clang";
           CXX = "clang++";
+          CMOCKA_MESSAGE_OUTPUT = "STANDARD";
+          LLVM_PROFILE_FILE = "output/prof/wamf-%p-%m.profraw";
         };
       };