Test: check the nix working path

Author: Damon Chen

nix/expansion.nix

@@ -11,8 +11,11 @@ stdenv.mkDerivation {
   ];
   buildCommand = ''
     mkdir -p $out
+    echo ${project_root}
     cp ${dotenv} $out
-    cd ${project_root}
-    python ${expansion}
+    pwd
+    ls
+    # cd ${project_root}
+    # python ${expansion}
   '';
 }