WORKS

modules/home-manager/default.nix

@@ -1,4 +1,3 @@
 {
-  # imports = [./mail.nix ./encryption.nix];
-  imports = [./mail.nix];
+  imports = [./mail.nix ./encryption.nix];
 }

modules/home-manager/encryption.nix

@@ -19,8 +19,16 @@ in {
 
       home.packages = with pkgs; [
         yubikey-personalization
-        gnupg
+        pinentry-gtk2
       ];
+      programs.gpg = {
+        enable = true;
+      };
+      services.gpg-agent = {
+        enable = true;
+        enableSshSupport = true;
+        pinentryPackage = pkgs.pinentry-gtk2;
+      };
 
       home.file.".ssh/config".source = ./ssh-config;
       home.file.".ssh/gpg-as-ssh.pub".source = ./gpg-as-ssh.pub;