diff --git a/pkgs/applications/science/math/perseus/default.nix b/pkgs/applications/science/math/perseus/default.nix
index a9cf6e1b018d..353d6691a9c9 100644
--- a/pkgs/applications/science/math/perseus/default.nix
+++ b/pkgs/applications/science/math/perseus/default.nix
@@ -13,7 +13,9 @@ stdenv.mkDerivation {
   };
 
   sourceRoot = ".";
+  
   NIX_CFLAGS_COMPILE = [ "-std=c++14" ];  # Otherwise it does not compile 
+  
   buildPhase = ''
     g++ Pers.cpp -O3 -fpermissive -o perseus
   '';