Add a calculator (bc)
diff --git a/modules/utilities.nix b/modules/utilities.nix
index 99e1253..c2ebfd9 100644
--- a/modules/utilities.nix
+++ b/modules/utilities.nix
@@ -3,6 +3,7 @@
   # them
   config.environment.systemPackages = with pkgs; [
     jq
+    bc
     (sd.overrideAttrs (oldAttrs: {
       postInstall = ''
         mv $out/bin/sd $out/bin/s