Hopefully this works! Adding release to continue.

nix/continue.nix

@@ -93,6 +93,35 @@ let
         "if (-not $?) { throw \"Error in build\" }"
       ];
     };
+    "Create release" = {
+      stage = "release";
+      image = "registry.gitlab.com/gitlab-org/release-cli:latest";
+      rules = [
+        {
+          if = "$CI_COMMIT_TAG";
+        }
+      ]; 
+      script = "echo \"Tagging as released\"";
+      needs = [
+        {
+          pipeline = "$PARENT_PIPELINE_ID";
+          job = "continue";
+          artifacts = true;
+        }
+        {
+          pipeline = "$PARENT_PIPELINE_ID";
+          job = "generate";
+          artifacts = true;
+        }
+      ];
+      release = {
+        tag_name = "$CI_COMMIT_TAG";
+        description = ''
+          Release $CI_COMMIT_TAG, found on [Vagrant Cloud](https://app.vagrantup.com/boxen/)
+          as version v''${BUILD}
+        '';
+      };
+    };
   };
 in
 pkgs.writeText "continue.yml" (builtins.toJSON continue)