add ethernetpad

module/etherpad/etherpad.nix

@@ -0,0 +1,54 @@
+{ config, lib, pkgs, ... }:
+
+{
+  ###### interface
+
+  options = {
+
+    services.etherpad = {
+
+      enable = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          Whether to enable etherpad service.
+        '';
+      };
+    };
+
+  };
+
+
+  ###### implementation
+
+  config =  mkIf cfg.enable{
+      environment.systemPackages = [pkgs.etherpad pkgs.nosdejs];
+      systemd.services.etherpad = {
+        description = "etherpad service";
+        serviceConfig = {
+          Type = "forking";
+          ExecStart = "${pkgs.etherpad}/bin/run.sh";
+        };
+        wantedBy = [ "multi-user.target" ];
+      };
+  };
+}
+
+{ stdenv, fetchFromGitHub }:
+
+stdenv.mkDerivation rec {
+  name= "etherpad-${version}";
+  version = "1.6.2";
+
+  src = fetchFromGitHub {
+    owner = "ether";
+    repo = " etherpad-lite";
+    rev = "${version}";
+    sha256 = "1zzx851603apysmzgxn6zqg779yak8r5vnafycy454wcgq6lb0bf";
+  };
+
+  installPhase = ''
+    mkdir -p $out/
+    cp -R . $out/
+  '';
+}