diff --git a/pkgs/development/python-modules/datatable/default.nix b/pkgs/development/python-modules/datatable/default.nix
index 004e47a60b5..3d3279bb2b3 100644
--- a/pkgs/development/python-modules/datatable/default.nix
+++ b/pkgs/development/python-modules/datatable/default.nix
@@ -61,5 +61,8 @@ buildPythonPackage rec {
     homepage = "https://github.com/h2oai/datatable";
     license = licenses.mpl20;
     maintainers = with maintainers; [ abbradar ];
+    # uses custom build system and adds -Wunused-variable -Werror
+    # warning: ‘dt::expr::doc_first’ defined but not used [-Wunused-variable]
+    broken = true;
   };
 }