adding nixosModule and test

flake.nix

@@ -1,38 +1,50 @@
 {
   description = "A very basic flake";
 
-  outputs = { self, nixpkgs }: {
+  #nixpkgs for testing framework
+  inputs.nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";
+
+  outputs = { self, nixpkgs, ... }: let
+    forAllSystems = nixpkgs.lib.genAttrs [ "x86_64-linux" ];
+  in
+  {
 
     packages.x86_64-linux.tasklist = nixpkgs.legacyPackages.x86_64-linux.buildGoModule rec {
       pname = "tasklist";
       version = "1.0";
       vendorHash = "sha256-olHQNClxU4sykBlhlbvTL6wCUYkMxnaQdLnRwvuJffw=";
       src = ./.;
+
+      postInstall = ''
+        cp forms.html $out/
+        '';
     };
 
-    nixosModules.malobeo-tasklist = { config, ... }: 
+    nixosModules.malobeo-tasklist = { config, lib, pkgs, ... }: 
     let
       cfg = config.services.malobeo-tasklist;
       tasklist-pkg = self.packages.x86_64-linux.tasklist;
+      pkgs = nixpkgs.legacyPackages."x86_64-linux";
     in
     {
       options = {
         services.malobeo-tasklist = {
-          enable = nixpkgs.lib.mkOption {
+          enable = lib.mkOption {
             default = false;
-            type = nixpkgs.types.bool;
-            description = nixpkgs.lib.mdDoc ''
+            type = lib.types.bool;
+            description = lib.mdDoc ''
               Enables tasklist
               '';
           };
         };
       };
 
-      config = nixpkgs.lib.mkIf cfg.enable {
-        environment.systemPackages = [ tasklist-pkg];
+      config = lib.mkIf cfg.enable {
+        environment.systemPackages = [ tasklist-pkg ];
 
-        users.users = {
-          malobeo-tasklist = {
+        users = {
+          groups.malobeo-tasklist = {};
+          users.malobeo-tasklist = {
             description = "malobeo tasklist user";
             group = "malobeo-tasklist";
             isNormalUser = true;
@@ -43,18 +55,32 @@
           description = "malobeo tasklist daemon";
           serviceConfig = {
             Type = "simple";
-            ExecStart = "${tasklist-pkg}/bin/tasklist -d /var/lib/malobeo-tasklist/tasklist.db";
+            ExecStart = "${tasklist-pkg}/bin/tasklist -d /var/lib/malobeo-tasklist/tasklist.db -f ${tasklist-pkg}/forms.html";
             Restart = "on-failure";
           };
 
+          preStart = ''
+              mkdir -m 0770 -p "/var/lib/malobeo-tasklist"
+              chown malobeo-tasklist:malobeo-tasklist "/var/lib/malobeo-tasklist"
+            '';
+
           wantedBy = [ "default.target" ];
 
           environment = {
             USER = "malobeo-tasklist";
-            HOME = /var/lib/malobeo-tasklist;
+            HOME = "/var/lib/malobeo-tasklist";
           };
         };
       };
     };
+
+    checks = forAllSystems (system: let
+      checkArgs = {
+        pkgs = nixpkgs.legacyPackages.${system};
+        inherit self;
+      };
+    in {
+      malobeo-tasklist = import ./test/test.nix checkArgs;
+    });
   };
 }