diff --git a/nix/coverage-html.nix b/nix/coverage-html.nix
index b66ef67..54b7ca0 100644
--- a/nix/coverage-html.nix
+++ b/nix/coverage-html.nix
@@ -49,6 +49,7 @@ stdenv.mkDerivation {
       -use-color
       -Xdemangler=c++filt
       -ignore-filename-regex='.*(test/).*'
+      -ignore-filename-regex='.*\.h'
       -compilation-dir=.
     )