modules/base.nix

@@ -49,9 +49,6 @@ in {
       type = types.attrsOf type_service;
     };
 
-    units = mkOption {
-      type = utils.systemdUtils.types.units;
-    };
     system.callService = mkOption {
       type = types.functionTo (types.functionTo types.anything);
     };

modules/systemd/default.nix

@@ -11,6 +11,7 @@ let
     nameValuePair
     mkMerge
     mapAttrsToList
+    mkOption
     ;
   inherit (pkgs.pseudofile) dir symlink;
   inherit (utils.systemdUtils.lib)
@@ -18,13 +19,15 @@ let
     serviceToUnit
     ;
 
+  systemd-types = import ./types.nix { inherit pkgs utils lib; };
+
   units-texts = mapAttrs' (
     _: unit:
     nameValuePair unit.name {
       file = unit.text;
       mode = "0644";
     }
-  ) config.units;
+  ) config.systemd.units;
   units-aliases = mkMerge (
     mapAttrsToList (
       _: unit:
@@ -33,7 +36,7 @@ let
           ${aka} = symlink "${unit.name}";
         }) (unit.aliases or [ ])
       )
-    ) config.units
+    ) config.systemd.units
   );
   units-extraWants = mkMerge (
     mapAttrsToList (
@@ -45,7 +48,7 @@ let
           };
         }) (unit.wantedBy or [ ])
       )
-    ) config.units
+    ) config.systemd.units
   );
   units-extraUpholds = mkMerge (
     mapAttrsToList (
@@ -57,7 +60,7 @@ let
           };
         }) (unit.upheldBy or [ ])
       )
-    ) config.units
+    ) config.systemd.units
   );
   units-extraRequires = mkMerge (
     mapAttrsToList (
@@ -69,49 +72,46 @@ let
           };
         }) (unit.requiredBy or [ ])
       )
-    ) config.units
+    ) config.systemd.units
   );
-
 in
 {
+  options = {
+    systemd = {
+      units = mkOption {
+        type = systemd-types.units;
+      };
+      services = mkOption {
+        type = systemd-types.services;
+      };
+      targets = mkOption {
+        type = systemd-types.targets;
+      };
+    };
+  };
   config = {
-    units = {
-      default-target = targetToUnit {
-        name = "default.target";
-        aliases = [];
-        wantedBy = [];
-        requiredBy = [];
-        upheldBy = [];
-        unitConfig.Description = "target to boot";
-      };
-      sysinit-target = targetToUnit {
-        name = "sysinit.target";
-        aliases = [];
-        wantedBy = [];
-        requiredBy = [];
-        upheldBy = [];
-        unitConfig.Description = "sysinit.target";
-      };
-      agetty = serviceToUnit {
-        name = "getty.service";
-        aliases = [];
-        wantedBy = [ "default.target" ];
-        requiredBy = [];
-        upheldBy = [];
-        environment = {};
-        unitConfig = {
-          Description = "Serial Shell";
-          Before = [ "default.target" ];
+    systemd = {
+      units = mkMerge [
+        (mapAttrs' (_: service: nameValuePair service.name (serviceToUnit service)) config.systemd.services)
+        (mapAttrs' (_: target: nameValuePair target.name (targetToUnit target)) config.systemd.targets)
+      ];
+      services = {
+        getty = {
+          wantedBy = [ "default.target" ];
+          unitConfig = {
+            Description = "Serial Shell";
+            Before = [ "default.target" ];
+          };
+          script = ''
+            #!/bin/ash
+            # . /etc/profile
+            exec /bin/ash < /dev/ttyS0 > /dev/ttyS0 2> /dev/ttyS0
+          '';
         };
-        serviceConfig.ExecStart =
-          let
-            login = pkgs.writeScript "login" ''
-              #!/bin/ash
-              . /etc/profile
-              exec /bin/ash
-            '';
-          in
-          "${pkgs.util-linux}/bin/agetty --login-program ${login} ttyS0";
+      };
+      targets = {
+        default = { };
+        sysinit = { };
       };
     };
 

modules/systemd/types.nix

@@ -0,0 +1,27 @@
+{
+  pkgs,
+  lib,
+  utils
+}:
+let
+  inherit (utils.systemdUtils.lib) serviceConfig unitConfig;
+  inherit (utils.systemdUtils.unitOptions) stage2ServiceOptions;
+  stage2ServiceConfig = {
+    imports = [ serviceConfig ];
+    # Default path for systemd services. Should be quite minimal.
+    config.path = lib.mkAfter [
+      pkgs.coreutils
+      # pkgs.gnugrep
+      # pkgs.gnused
+      pkgs.systemd
+    ];
+  };
+in
+{
+  inherit (utils.systemdUtils.types) units targets;
+  services = lib.types.attrsOf (lib.types.submodule [
+    unitConfig
+    stage2ServiceOptions
+    stage2ServiceConfig
+  ]);
+}