diff --git a/shell.nix b/shell.nix
index ab1fe93..30377b2 100644
--- a/shell.nix
+++ b/shell.nix
@@ -2,4 +2,6 @@
 
 with pkgs;
 
-mkShell { buildInputs = [ python39 python39Packages.pandas ]; }
+mkShell {
+  buildInputs = [ python39 python39Packages.numpy python39Packages.pandas ];
+}