diff --git a/flake.nix b/flake.nix
index 41410ef..42d143a 100644
--- a/flake.nix
+++ b/flake.nix
@@ -67,6 +67,9 @@
           ] ++ (with python3Packages; [
             numpy matplotlib
           ]);
+        shellHook = ''
+          export PYTHONPATH=`pwd`/pytec:$PYTHONPATH
+        '';
       };
     };
 }
\ No newline at end of file