diff --git a/etc/default.nix b/etc/default.nix
index 7cffdf082aad..6b15245e4cb1 100644
--- a/etc/default.nix
+++ b/etc/default.nix
@@ -134,33 +134,8 @@ let
       target = "skel/.bashrc";      
     }
 
-    { # SSH configuration.  Slight duplication of the sshd_config
-      # generation in the sshd service.
-      source = pkgs.writeText "ssh_config" ''
-        ${if config.services.sshd.forwardX11 then ''
-          ForwardX11 yes
-          XAuthLocation ${pkgs.xorg.xauth}/bin/xauth
-        '' else ''
-          ForwardX11 no
-        ''}
-      '';
-      target = "ssh/ssh_config";
-    }
   ]
 
-  # Configuration for ssmtp.
-  ++ optional config.networking.defaultMailServer.directDelivery { 
-    source = let cfg = config.networking.defaultMailServer; in pkgs.writeText "ssmtp.conf" ''
-      MailHub=${cfg.hostName}
-      FromLineOverride=YES
-      ${if cfg.domain != "" then "rewriteDomain=${cfg.domain}" else ""}
-      UseTLS=${if cfg.useTLS then "YES" else "NO"}
-      UseSTARTTLS=${if cfg.useSTARTTLS then "YES" else "NO"}
-      #Debug=YES
-    '';
-    target = "ssmtp/ssmtp.conf";
-  }
-
   # A bunch of PAM configuration files for various programs.
   ++ (map
     (program:
diff --git a/modules/config/system-path.nix b/modules/config/system-path.nix
index 41903297252a..c5708a530624 100644
--- a/modules/config/system-path.nix
+++ b/modules/config/system-path.nix
@@ -71,7 +71,6 @@ let
       (import ../../helpers/info-wrapper.nix {inherit (pkgs) bash texinfo writeScriptBin;})
     ]
     ++ pkgs.lib.optional config.services.bitlbee.enable pkgs.bitlbee
-    ++ pkgs.lib.optional config.networking.defaultMailServer.directDelivery pkgs.ssmtp 
     ++ config.environment.extraPackages
     ++ pkgs.lib.optional config.fonts.enableFontDir config.system.build.x11Fonts
 
diff --git a/modules/module-list.nix b/modules/module-list.nix
index 19fc5d10fbfc..96e276df98d2 100644
--- a/modules/module-list.nix
+++ b/modules/module-list.nix
@@ -1,4 +1,4 @@
-[ # This file have been generated by gen-module-list.sh
+[ # This file has been generated by gen-module-list.sh
   ./config/fonts.nix
   ./config/i18n.nix
   ./config/nsswitch.nix
@@ -8,6 +8,8 @@
   ./config/users-groups.nix
   ./installer/grub/grub.nix
   ./legacy.nix
+  ./programs/ssh.nix
+  ./programs/ssmtp.nix
   ./security/setuid-wrappers.nix
   ./security/sudo.nix
   ./services/audio/alsa.nix
diff --git a/modules/programs/ssh.nix b/modules/programs/ssh.nix
new file mode 100644
index 000000000000..c325a4bea34d
--- /dev/null
+++ b/modules/programs/ssh.nix
@@ -0,0 +1,20 @@
+# Global configuration for the SSH client.
+
+{config, pkgs, ...}:
+
+{
+  environment.etc =
+    [ { # SSH configuration.  Slight duplication of the sshd_config
+        # generation in the sshd service.
+        source = pkgs.writeText "ssh_config" ''
+          ${if config.services.sshd.forwardX11 then ''
+            ForwardX11 yes
+            XAuthLocation ${pkgs.xorg.xauth}/bin/xauth
+          '' else ''
+            ForwardX11 no
+          ''}
+        '';
+        target = "ssh/ssh_config";
+      }
+    ];
+}
diff --git a/modules/programs/ssmtp.nix b/modules/programs/ssmtp.nix
new file mode 100644
index 000000000000..a0ecf763528e
--- /dev/null
+++ b/modules/programs/ssmtp.nix
@@ -0,0 +1,91 @@
+# Configuration for `ssmtp', a trivial mail transfer agent that can
+# replace sendmail/postfix on simple systems.  It delivers email
+# directly to an SMTP server defined in its configuration file, wihout
+# queueing mail locally.
+
+{config, pkgs, ...}:
+
+with pkgs.lib;
+
+let
+
+  options = {
+
+    networking.defaultMailServer = {
+
+      directDelivery = mkOption {
+        default = false;
+        example = true;
+        description = "
+          Use the trivial Mail Transfer Agent (MTA)
+          <command>ssmtp</command> package to allow programs to send
+          e-mail.  If you don't want to run a ``real'' MTA like
+          <command>sendmail</command> or <command>postfix</command> on
+          your machine, set this option to <literal>true</literal>, and
+          set the option
+          <option>networking.defaultMailServer.hostName</option> to the
+          host name of your preferred mail server.
+        ";
+      };
+
+      hostName = mkOption {
+        example = "mail.example.org";
+        description = "
+          The host name of the default mail server to use to deliver
+          e-mail.
+        ";
+      };
+
+      domain = mkOption {
+        default = "";
+        example = "example.org";
+        description = "
+          The domain from which mail will appear to be sent.
+        ";
+      };
+
+      useTLS = mkOption {
+        default = false;
+        example = true;
+        description = "
+          Whether TLS should be used to connect to the default mail
+          server.
+        ";
+      };
+
+      useSTARTTLS = mkOption {
+        default = false;
+        example = true;
+        description = "
+          Whether the STARTTLS should be used to connect to the default
+          mail server.  (This is needed for TLS-capable mail servers
+          running on the default SMTP port 25.)
+        ";
+      };
+
+    };
+
+  };
+
+  cfg = config.networking.defaultMailServer;
+
+in
+
+mkIf cfg.directDelivery {
+  require = [options];
+
+  environment.etc =
+    [ { source = pkgs.writeText "ssmtp.conf" ''
+          MailHub=${cfg.hostName}
+          FromLineOverride=YES
+          ${if cfg.domain != "" then "rewriteDomain=${cfg.domain}" else ""}
+          UseTLS=${if cfg.useTLS then "YES" else "NO"}
+          UseSTARTTLS=${if cfg.useSTARTTLS then "YES" else "NO"}
+          #Debug=YES
+        '';
+        target = "ssmtp/ssmtp.conf";
+      }
+    ];
+
+  environment.extraPackages = [pkgs.ssmtp];
+}
diff --git a/system/options.nix b/system/options.nix
index f070d8674164..8e3308174e73 100644
--- a/system/options.nix
+++ b/system/options.nix
@@ -85,60 +85,6 @@ in
       ";
     };
 
-    defaultMailServer = {
-
-      directDelivery = mkOption {
-        default = false;
-        example = true;
-        description = "
-          Use the trivial Mail Transfer Agent (MTA)
-          <command>ssmtp</command> package to allow programs to send
-          e-mail.  If you don't want to run a ``real'' MTA like
-          <command>sendmail</command> or <command>postfix</command> on
-          your machine, set this option to <literal>true</literal>, and
-          set the option
-          <option>networking.defaultMailServer.hostName</option> to the
-          host name of your preferred mail server.
-        ";
-      };
-
-      hostName = mkOption {
-        example = "mail.example.org";
-        description = "
-          The host name of the default mail server to use to deliver
-          e-mail.
-        ";
-      };
-
-      domain = mkOption {
-        default = "";
-        example = "example.org";
-        description = "
-          The domain from which mail will appear to be sent.
-        ";
-      };
-
-      useTLS = mkOption {
-        default = false;
-        example = true;
-        description = "
-          Whether TLS should be used to connect to the default mail
-          server.
-        ";
-      };
-
-      useSTARTTLS = mkOption {
-        default = false;
-        example = true;
-        description = "
-          Whether the STARTTLS should be used to connect to the default
-          mail server.  (This is needed for TLS-capable mail servers
-          running on the default SMTP port 25.)
-        ";
-      };
-
-    };
-
   };