update to include java (eugh) and create a nixosModule

flake.nix

@@ -10,12 +10,39 @@
       pkgs = nixpkgs.legacyPackages.x86_64-linux;
     in
     {
+      nixosModule = { options, lib, config, pkgs, ... }:
+        let
+          serviceConfig = config.services.mossnet.dhyan;
+          options.enable = lib.mkEnableOption "Dhyan daily runner";
+        in
+        {
+          options.services.mossnet.dhyan = options;
+          config = lib.mkIf serviceConfig.enable {
+            systemd.services."dhyan" = {
+              description = ''
+                Various matrix bot integrations
+              '';
+              wantedBy = [ "multi-user.target" ];
+              serviceConfig = { Type = "oneshot"; };
+              startsAt = "*08:00:00";
+              path = with pkgs; [ babashka jdk11 ];
+              script = ''
+                set -ex 
+                cd ~/usr/dhyan
+                bb -m dhyan.main
+              '';
+
+            };
+          };
+        };
       devShell.x86_64-linux = pkgs.mkShell {
         buildInputs = with pkgs; [
+          jdk11
           babashka
         ];
         shellHook = ''
-          [[ -z $token ]] && echo "::dhyan:: Necessary Env Var missing: token"
+          [[ -z $SHAARLI_TOKEN ]] && echo "::dhyan:: Necessary Env Var missing: SHAARLI_TOKEN"
+          [[ -z $MATRIX_PASSWORD ]] && echo "::dhyan:: Necessary Env Var missing: MATRIX_PASSWORD"
           [[ -z $folder ]] && echo "::dhyan:: Necessary Env Var missing: folder"
         '';
       };