diff --git a/flake.nix b/flake.nix
index eaeb561..ac89180 100644
--- a/flake.nix
+++ b/flake.nix
@@ -159,6 +159,9 @@
             pglive
             qtextras
           ]);
+          shellHook = ''
+            export PYTHONPATH=`pwd`/pytec:$PYTHONPATH
+          '';
       };
       defaultPackage.x86_64-linux = thermostat;
     };