diff --git a/modules/config/system-path.nix b/modules/config/system-path.nix
new file mode 100644
index 0000000..b101191
--- /dev/null
+++ b/modules/config/system-path.nix
@@ -0,0 +1,149 @@
+# This module defines the packages that appear in
+# /run/current-system/sw.
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+
+  makeDrvBinPath = lib.concatMapStringsSep ":" (p: if lib.isDerivation p then "${p}/bin" else p);
+
+  defaultPackageNames = [ ];
+  defaultPackages = map (
+    n:
+    let
+      pkg = pkgs.${n};
+    in
+    lib.setPrio ((pkg.meta.priority or lib.meta.defaultPriority) + 3) pkg
+  ) defaultPackageNames;
+  defaultPackagesText = "[ ${lib.concatMapStringsSep " " (n: "pkgs.${n}") defaultPackageNames} ]";
+
+in
+
+{
+  imports = [
+    (lib.mkRenamedOptionModule ["environment" "postBuild"] ["environment" "extraSetup"])
+  ];
+
+  options = {
+
+    environment = {
+      systemPath = lib.mkOption {
+        type = lib.types.listOf (lib.types.either lib.types.path lib.types.str);
+        description = "The set of paths that are added to PATH.";
+        apply = x: if lib.isList x then makeDrvBinPath x else x;
+      };
+
+      systemPackages = lib.mkOption {
+        type = lib.types.listOf lib.types.package;
+        default = [ ];
+        example = lib.literalExpression "[ pkgs.firefox pkgs.thunderbird ]";
+        description = ''
+          The set of packages that appear in
+          /run/current-system/sw.  These packages are
+          automatically available to all users, and are
+          automatically updated every time you rebuild the system
+          configuration.  (The latter is the main difference with
+          installing them in the default profile,
+          {file}`/nix/var/nix/profiles/default`.
+        '';
+      };
+
+      defaultPackages = lib.mkOption {
+        type = lib.types.listOf lib.types.package;
+        default = defaultPackages;
+        defaultText = lib.literalMD ''
+          these packages, with their `meta.priority` numerically increased
+          (thus lowering their installation priority):
+
+              ${defaultPackagesText}
+        '';
+        example = [ ];
+        description = ''
+          Set of default packages that aren't strictly necessary
+          for a running system, entries can be removed for a more
+          minimal NixOS installation.
+
+          Like with systemPackages, packages are installed to
+          {file}`/run/current-system/sw`. They are
+          automatically available to all users, and are
+          automatically updated every time you rebuild the system
+          configuration.
+        '';
+      };
+
+      pathsToLink = lib.mkOption {
+        type = lib.types.listOf lib.types.str;
+        # According to https://github.com/NixOS/nixpkgs/blob/2795c506fe8fb7b03c36ccb51f75b6df0ab2553f/nixos/modules/config/system-path.nix#L108-L109
+        # `/lib` needs to be added to make NSS modules work, however currently we don't add it
+        # and it's unclear whether the comment applies on macOS as well.
+        default = [ ];
+        example = [ "/share/doc" ];
+        description = "List of directories to be symlinked in {file}`/run/current-system/sw`.";
+      };
+
+      extraOutputsToInstall = lib.mkOption {
+        type = lib.types.listOf lib.types.str;
+        default = [ ];
+        example = [
+          "dev"
+          "info"
+        ];
+        description = ''
+          Entries listed here will be appended to the `meta.outputsToInstall` attribute for each package in `environment.systemPackages`, and the files from the corresponding derivation outputs symlinked into {file}`/run/current-system/sw`.
+
+          For example, this can be used to install the `dev` and `info` outputs for all packages in the system environment, if they are available.
+
+          To use specific outputs instead of configuring them globally, select the corresponding attribute on the package derivation, e.g. `libxml2.dev` or `coreutils.info`.
+        '';
+      };
+
+      extraSetup = lib.mkOption {
+        type = lib.types.lines;
+        default = "";
+        description = "Shell fragments to be run after the system environment has been created. This should only be used for things that need to modify the internals of the environment, e.g. generating MIME caches. The environment being built can be accessed at $out.";
+      };
+
+    };
+
+    system = {
+
+      path = lib.mkOption {
+        internal = true;
+        description = ''
+          The packages you want in the system environment.
+        '';
+      };
+
+    };
+
+  };
+
+  config = {
+
+    environment.systemPackages = config.environment.defaultPackages;
+
+    environment.pathsToLink = [
+      "/bin"
+      "/share/locale"
+    ];
+
+    system.path = pkgs.buildEnv {
+      name = "system-path";
+      paths = config.environment.systemPackages;
+      inherit (config.environment) pathsToLink extraOutputsToInstall;
+      ignoreCollisions = true;
+      # !!! Hacky, should modularise.
+      # outputs TODO: note that the tools will often not be linked by default
+      postBuild = ''
+        # Remove wrapped binaries, they shouldn't be accessible via PATH.
+        find $out/bin -maxdepth 1 -name ".*-wrapped" -type l -delete
+
+        ${config.environment.extraSetup}
+      '';
+    };
+
+  };
+}
diff --git a/modules/environment/default.nix b/modules/environment/default.nix
index b2f37c6..632a914 100644
--- a/modules/environment/default.nix
+++ b/modules/environment/default.nix
@@ -11,13 +11,10 @@ let
   aliasCommands =
     mapAttrsToList (n: v: ''alias ${n}=${escapeShellArg v}'')
       (filterAttrs (k: v: v != null) cfg.shellAliases);
-
-  makeDrvBinPath = concatMapStringsSep ":" (p: if isDerivation p then "${p}/bin" else p);
 in
 
 {
   imports = [
-    (mkRenamedOptionModule ["environment" "postBuild"] ["environment" "extraSetup"])
     (mkRemovedOptionModule [ "environment" "loginShell" ] ''
       This option was only used to change the default command in tmux.
 
@@ -26,46 +23,11 @@ in
   ];
 
   options = {
-    environment.systemPackages = mkOption {
-      type = types.listOf types.package;
-      default = [];
-      example = literalExpression "[ pkgs.curl pkgs.vim ]";
-      description = ''
-        The set of packages that appear in
-        /run/current-system/sw.  These packages are
-        automatically available to all users, and are
-        automatically updated every time you rebuild the system
-        configuration.  (The latter is the main difference with
-        installing them in the default profile,
-        {file}`/nix/var/nix/profiles/default`.
-      '';
-    };
-
-    environment.systemPath = mkOption {
-      type = types.listOf (types.either types.path types.str);
-      description = "The set of paths that are added to PATH.";
-      apply = x: if isList x then makeDrvBinPath x else x;
-    };
-
     environment.profiles = mkOption {
       type = types.listOf types.str;
       description = "A list of profiles used to setup the global environment.";
     };
 
-    environment.extraOutputsToInstall = mkOption {
-      type = types.listOf types.str;
-      default = [];
-      example = [ "doc" "info" "devdoc" ];
-      description = "List of additional package outputs to be symlinked into {file}`/run/current-system/sw`.";
-    };
-
-    environment.pathsToLink = mkOption {
-      type = types.listOf types.str;
-      default = [];
-      example = [ "/share/doc" ];
-      description = "List of directories to be symlinked in {file}`/run/current-system/sw`.";
-    };
-
     environment.darwinConfig = mkOption {
       type = types.nullOr (types.either types.path types.str);
       default =
@@ -160,17 +122,6 @@ in
       '';
       type = types.lines;
     };
-
-    environment.extraSetup = mkOption {
-      type = types.lines;
-      default = "";
-      description = ''
-        Shell fragments to be run after the system environment has been created.
-        This should only be used for things that need to modify the internals
-        of the environment, e.g. generating MIME caches.
-        The environment being built can be accessed at $out.
-      '';
-    };
   };
 
   config = {
@@ -196,11 +147,6 @@ in
       [ "/run/current-system/sw" "/nix/var/nix/profiles/default" ]
     ];
 
-    environment.pathsToLink = [
-      "/bin"
-      "/share/locale"
-    ];
-
     environment.extraInit = ''
        export NIX_USER_PROFILE_DIR="/nix/var/nix/profiles/per-user/$USER"
        export NIX_PROFILES="${concatStringsSep " " (reverseList cfg.profiles)}"
@@ -214,14 +160,6 @@ in
         PAGER = mkDefault "less -R";
       };
 
-    system.path = pkgs.buildEnv {
-      name = "system-path";
-      paths = cfg.systemPackages;
-      postBuild = cfg.extraSetup;
-      ignoreCollisions = true;
-      inherit (cfg) pathsToLink extraOutputsToInstall;
-    };
-
     system.build.setEnvironment = pkgs.writeText "set-environment" ''
       # Prevent this file from being sourced by child shells.
       export __NIX_DARWIN_SET_ENVIRONMENT_DONE=1
diff --git a/modules/module-list.nix b/modules/module-list.nix
index 1ddb95b..ff57502 100644
--- a/modules/module-list.nix
+++ b/modules/module-list.nix
@@ -1,5 +1,6 @@
 [
   ./alias.nix
+  ./config/system-path.nix
   ./config/terminfo.nix
   ./documentation
   ./meta.nix
diff --git a/modules/system/default.nix b/modules/system/default.nix
index 733a73a..c484e38 100644
--- a/modules/system/default.nix
+++ b/modules/system/default.nix
@@ -27,14 +27,6 @@ in
       '';
     };
 
-    system.path = mkOption {
-      internal = true;
-      type = types.package;
-      description = ''
-        The packages you want in the system environment.
-      '';
-    };
-
     system.profile = mkOption {
       type = types.path;
       default = "/nix/var/nix/profiles/system";