diff --git a/README.md b/README.md
index 4f7e189..719756b 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,8 @@ NixOS dotfiles and configuration for various hosts and users.
 
 - `users/<name>/`: Global configurations for individual users that apply across all hosts. This includes secrets (like GPG keys and third-party service passwords), wallpapers, and more.
 
+- [`lib/`](./lib): Nix library function definitions and utilities.
+
 - [`scripts/`](./scripts): Utility scripts for managing the repository.
   - [`add-host.sh`](./scripts/add-host.sh): Instantiate the keys for a new host configuration.
   - [`remove-host.sh`](./scripts/remove-host.sh): Remove references to a host.
diff --git a/hosts/common/user/configs/gui/spicetify/config/prefs b/hosts/common/user/configs/gui/spicetify/config/prefs
index 374b94b..5028bbb 100644
--- a/hosts/common/user/configs/gui/spicetify/config/prefs
+++ b/hosts/common/user/configs/gui/spicetify/config/prefs
@@ -1,2 +1 @@
 app.autostart-mode="off"
-storage.last-location="/home/nick/.cache/spotify/Storage"
diff --git a/hosts/common/user/configs/gui/spicetify/config/user-prefs b/hosts/common/user/configs/gui/spicetify/config/prefs-user
similarity index 100%
rename from hosts/common/user/configs/gui/spicetify/config/user-prefs
rename to hosts/common/user/configs/gui/spicetify/config/prefs-user
diff --git a/hosts/common/user/configs/gui/spicetify/default.nix b/hosts/common/user/configs/gui/spicetify/default.nix
index dd27056..54999fb 100644
--- a/hosts/common/user/configs/gui/spicetify/default.nix
+++ b/hosts/common/user/configs/gui/spicetify/default.nix
@@ -9,6 +9,9 @@
   pkgs,
   ...
 }:
+let
+  hmConfig = config.home-manager.users.${user};
+in
 {
   networking.firewall = {
     allowedTCPPorts = [ 57621 ];
@@ -59,84 +62,22 @@
         ];
       };
 
-    systemd.user = {
-      services =
-        let
-          merge = lib.meta.getExe (
-            pkgs.writeShellApplication {
-              name = "merge";
-              runtimeInputs = with pkgs; [
-                gnugrep
-                coreutils
-              ];
-              text = builtins.readFile ./config/merge.sh;
-            }
-          );
-        in
-        {
-          spotify-init = {
-            Unit = {
-              Description = "Populate Spotify preferences from template";
-              After = config.environment.persistence."/persist"."${home}/.config/spotify".mount;
-              DefaultDependencies = false;
-            };
+    sops.secrets."spotify/username" = { };
 
-            Service = {
-              ExecStart = "${merge} ${./config/prefs} ${home}/.config/spotify/prefs";
-              Type = "oneshot";
-              RemainAfterExit = true;
-            };
-          };
+    xdg.configFile = {
+      "spotify/prefs.init" = {
+        source = ./config/prefs;
+        onChange = ''
+          ${config.lib.runtime.merge.keyValue} "${home}/.config/spotify/prefs.init" "${home}/.config/spotify/prefs"
+        '';
+      };
 
-          spotify-init-user = {
-            Unit = {
-              Description = "Populate Spotify user preferences from template";
-              After = config.environment.persistence."/persist"."${home}/.config/spotify".mount;
-              DefaultDependencies = false;
-            };
-
-            Service = {
-              ExecStart = lib.meta.getExe (
-                pkgs.writeShellApplication {
-                  name = "merge-user";
-                  text = ''
-                    for USER_DIR in ${home}/.config/spotify/Users/*/; do
-                      ${merge} ${./config/user-prefs} "$USER_DIR/prefs"
-                    done
-                  '';
-                }
-              );
-              Type = "oneshot";
-              RemainAfterExit = true;
-            };
-          };
-        };
-
-      paths = {
-        spotify-init = {
-          Unit = {
-            Description = "Monitor Spotify directory";
-            After = config.environment.persistence."/persist"."${home}/.config/spotify".mount;
-          };
-
-          Path.PathExists = "${home}/.config/spotify";
-
-          Install.WantedBy = [ "graphical-session.target" ];
-        };
-
-        spotify-init-user = {
-          Unit = {
-            Description = "Monitor Spotify user directory";
-            After = config.environment.persistence."/persist"."${home}/.config/spotify".mount;
-          };
-
-          Path = {
-            PathExists = "${home}/.config/spotify/Users";
-            PathModified = "${home}/.config/spotify/Users";
-          };
-
-          Install.WantedBy = [ "graphical-session.target" ];
-        };
+      "spotify/prefs-user.init" = {
+        source = ./config/prefs-user;
+        onChange = ''
+          user = $(cat "${hmConfig.sops.secrets."spotify/username".path}")
+          ${config.lib.runtime.merge.keyValue} "${home}/.config/spotify/prefs-user.init" "${home}/.config/spotify/Users/''${user}-user/prefs"
+        '';
       };
     };
 
diff --git a/hosts/eirene/README.md b/hosts/eirene/README.md
index 689d669..38a8631 100644
--- a/hosts/eirene/README.md
+++ b/hosts/eirene/README.md
@@ -15,6 +15,7 @@
 
 - [ ] Spotify
   - [ ] Authenticate
+  - [ ] Local Files
 
 - [ ] Steam
   - [ ] Authenticate
diff --git a/hosts/eirene/default.nix b/hosts/eirene/default.nix
index 85b0999..83a99d5 100644
--- a/hosts/eirene/default.nix
+++ b/hosts/eirene/default.nix
@@ -6,6 +6,7 @@
 }:
 {
   imports = [
+    ../../lib
     inputs.disko.nixosModules.disko
     (import ./format.nix { device = "/dev/disk/by-id/nvme-SAMSUNG_MZVL22T0HBLB-00BL2_S64RNE0R602762"; })
     ./hardware-configuration.nix
diff --git a/lib/default.nix b/lib/default.nix
new file mode 100644
index 0000000..6dd8e76
--- /dev/null
+++ b/lib/default.nix
@@ -0,0 +1,6 @@
+{ pkgs, ... }:
+{
+  lib = {
+    runtime = pkgs.callPackage ./runtime { };
+  };
+}
diff --git a/lib/runtime/default.nix b/lib/runtime/default.nix
new file mode 100644
index 0000000..2b6a45b
--- /dev/null
+++ b/lib/runtime/default.nix
@@ -0,0 +1,4 @@
+{ pkgs, ... }:
+{
+  merge = pkgs.callPackage ./merge { };
+}
diff --git a/lib/runtime/merge/default.nix b/lib/runtime/merge/default.nix
new file mode 100644
index 0000000..ae4daec
--- /dev/null
+++ b/lib/runtime/merge/default.nix
@@ -0,0 +1,13 @@
+{ lib, pkgs, ... }:
+{
+  keyValue = lib.meta.getExe (
+    pkgs.writeShellApplication {
+      name = "merge-key-value";
+      runtimeInputs = with pkgs; [
+        gnugrep
+        coreutils
+      ];
+      text = builtins.readFile ./key-value.sh;
+    }
+  );
+}
diff --git a/hosts/common/user/configs/gui/spicetify/config/merge.sh b/lib/runtime/merge/key-value.sh
similarity index 100%
rename from hosts/common/user/configs/gui/spicetify/config/merge.sh
rename to lib/runtime/merge/key-value.sh