diff --git a/modules/services/web-apps/betanin.nix b/modules/services/web-apps/betanin.nix
index 662adc5..988ac19 100644
--- a/modules/services/web-apps/betanin.nix
+++ b/modules/services/web-apps/betanin.nix
@@ -1,17 +1,47 @@
 { config, lib, pkgs, ... }:
 
 let
-  inherit (lib) mkIf mkOption optionalAttrs types;
+  inherit (lib) mkIf mkOption optionalAttrs optionalString types;
   cfg = config.services.betanin;
 
-  yaml = pkgs.formats.yaml { };
-  configFile =
-    if (cfg.beetsConfigFile != null)
-    then cfg.beetsConfigFile
-    else yaml.generate "beets-config.yaml" cfg.beetsConfig;
-
   defaultUser = "betanin";
   defaultGroup = "betanin";
+  defaultSettings = {
+    notifications = {
+      services = { };
+      strings = {
+        title = "[betanin] torrent `$name` $status";
+        body = "@ $time. view/use the console at http://127.0.0.1:${toString cfg.port}/$console_path";
+      };
+    };
+  };
+
+  finalSettings =
+    let
+      base = lib.filterAttrsRecursive (n: _: !(lib.hasSuffix "_file" n)) cfg.settings;
+      clean = {
+        frontend.password =
+          if cfg.settings.frontend.password_file != null
+          then "@password@"
+          else cfg.settings.frontend.password;
+        clients.api_key =
+          if cfg.settings.clients.api_key_file != null
+          then "@api_key@"
+          else cfg.settings.clients.api_key;
+      };
+    in
+    lib.foldl' lib.recursiveUpdate defaultSettings [ base clean ];
+
+  settingsFormat = pkgs.formats.toml { };
+  settingsFile = settingsFormat.generate "betanin.toml" finalSettings;
+
+  beetsFormat = pkgs.formats.yaml { };
+  beetsFile =
+    if (cfg.beetsFile != null)
+    then cfg.beetsFile
+    else if (cfg.beetsConfig != { })
+    then beetsFormat.generate "betanin-beets.yaml" cfg.beetsConfig
+    else null;
 in
 {
   options = {
@@ -54,51 +84,158 @@ in
         default = "/var/lib/betanin";
       };
 
+      settings = mkOption {
+        type = types.submodule {
+          freeformType = settingsFormat.type;
+
+          options.frontend.username = mkOption {
+            type = types.str;
+            default = "";
+            description = "Username used to log into the frontend. Must be set.";
+          };
+
+          options.frontend.password = mkOption {
+            type = types.str;
+            default = "";
+            description = ''
+              Password used to log into the frontend. Either password or
+              password_file must be set.
+            '';
+          };
+
+          options.frontend.password_file = mkOption {
+            type = with types; nullOr (either str path);
+            default = null;
+            description = ''
+              File containing the password used to log into the frontend. The
+              file must be readable by the betanin user/group.
+
+              Using a password file keeps the password out of the Nix store, but
+              the password is still stored in plain text in the service data
+              directory.
+            '';
+          };
+
+          options.clients.api_key = mkOption {
+            type = types.nullOr types.str;
+            default = "";
+            description = ''
+              API key used to access Betanin (e.g., from other services).
+            '';
+          };
+
+          options.clients.api_key_file = mkOption {
+            type = with types; nullOr (either str path);
+            default = null;
+            description = ''
+              File containing the API key used to access Betanin (e.g., from
+              other services). The file must be readable by the betanin
+              user/group.
+
+              Using a API key file keeps the API key out of the Nix store, but
+              the API key is still stored in plain text in the service data
+              directory.
+            '';
+          };
+        };
+        default = defaultSettings;
+        example = lib.literalExpression ''
+          {
+            frontend = {
+              username = "foo";
+              password_file = "/run/secrets/betaninPasswordFile";
+            };
+            clients = {
+              api_key_file = "/run/secrets/betaninApiKeyFile";
+            };
+            server = {
+              num_parallel_jobs = 1;
+            };
+          }
+        '';
+        description = "Configuration for betanin.";
+      };
+
       beetsConfig = mkOption {
         description = "beets configuration.";
-        type = yaml.type;
+        type = beetsFormat.type;
         default = { };
       };
 
-      beetsConfigFile = mkOption {
+      beetsFile = mkOption {
         description = "beets configuration file.";
-        type = nullOr (either str path);
+        type = with types; nullOr (either str path);
         default = null;
       };
     };
   };
 
   config = mkIf cfg.enable {
-    assertions = [{
-      assertion = (cfg.beetsConfig == { }) != (cfg.beetsConfigFile == null);
-      message = "either services.betanin.beetsConfig or services.betanin.beetsConfigFile is required";
-    }];
+    assertions = [
+      {
+        assertion = cfg.settings.frontend.username != "";
+        message = "services.betanin.settings.frontend.username is required";
+      }
+      {
+        assertion = (cfg.settings.frontend.password == "") != (cfg.settings.frontend.password_file == null);
+        message = "services.betanin.settings.frontend.password or services.betanin.settings.frontend.password_file is required";
+      }
+      {
+        assertion = (cfg.settings.clients.api_key == "") != (cfg.settings.clients.api_key_file == null);
+        message = "services.betanin.settings.clients.api_key or services.betanin.settings.clients.api_key_file is required";
+      }
+    ];
 
     networking.firewall = mkIf cfg.openFirewall {
       allowedTCPPorts = [ cfg.port ];
     };
 
-    systemd.services.betanin = {
-      description = "Betanin service";
-      wantedBy = [ "multi-user.target" ];
-      after = [ "networking.target" ];
-      environment = {
-        HOME = cfg.dataDir;
+    systemd.services.betanin =
+      let
+        replaceSecret = secretFile: placeholder: targetFile:
+          optionalString (secretFile != null) ''
+            ${pkgs.replace-secret}/bin/replace-secret ${placeholder} ${secretFile} ${targetFile}
+          '';
+        replaceConfigSecret = secretFile: placeholder:
+          replaceSecret secretFile placeholder "${cfg.dataDir}/.config/betanin/config.toml";
+      in
+      {
+        description = "Betanin service";
+        wantedBy = [ "multi-user.target" ];
+        after = [ "networking.target" ];
+        environment = {
+          HOME = cfg.dataDir;
+        };
+        path = [ pkgs.replace-secret ];
+
+        script = ''
+          mkdir -p ${cfg.dataDir}/.config/betanin \
+            ${cfg.dataDir}/.config/beets \
+            ${cfg.dataDir}/.local/share/betanin
+          cat ${settingsFile} > ${cfg.dataDir}/.config/betanin/config.toml
+
+          ${optionalString (beetsFile != null) ''
+            ln -sf ${beetsFile} ${cfg.dataDir}/.config/betanin/config.toml
+          ''}
+          ${replaceConfigSecret cfg.settings.frontend.password_file "@password@"}
+          ${replaceConfigSecret cfg.settings.clients.api_key_file "@api_key@"}
+
+          ${cfg.package}/bin/betanin --port ${toString cfg.port}
+        '';
+
+        serviceConfig = lib.mkMerge [
+          {
+            User = cfg.user;
+            Group = cfg.group;
+            PrivateTmp = true;
+            Restart = "always";
+            WorkingDirectory = cfg.dataDir;
+          }
+          (mkIf (cfg.dataDir == "/var/lib/betanin") {
+            StateDirectory = "betanin";
+          })
+        ];
       };
-      serviceConfig = lib.mkMerge [
-        {
-          User = cfg.user;
-          Group = cfg.group;
-          ExecStart = "${cfg.package}/bin/betanin --port ${cfg.port}";
-          PrivateTmp = true;
-          Restart = "always";
-          WorkingDirectory = cfg.dataDir;
-        }
-        (mkIf (cfg.dataDir == "/var/lib/betanin") {
-          StateDirectory = "betanin";
-        })
-      ];
-    };
 
     users.users = optionalAttrs (cfg.user == defaultUser) {
       ${cfg.user} = {