diff --git a/CHANGELOG.md b/CHANGELOG.md
index ade56a63..7005c0d4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,7 @@
 ### Unreleased
 
+* Validate param key exists, not the value
+
 ### 2.0.3
 
 * Notifier generator now ensures the `Notifier` suffix.
diff --git a/README.md b/README.md
index 9651b137..0096f328 100644
--- a/README.md
+++ b/README.md
@@ -587,6 +587,14 @@ end
 # @post.noticed_events.each { |ne| ne.notifications... }
 ```
 
+#### ActiveJob Parent Class
+
+Noticed uses its own `Noticed::ApplicationJob` as the base job for all notifications.  In the event that you would like to customize the parent job class, there is a `parent_class` attribute that can be overridden with your own class.  This should be done in a `noticed.rb` initializer.
+
+```ruby
+Noticed.parent_class = "ApplicationJob"
+```
+
 #### Handling Deleted Records
 
 Generally we recommend using a `dependent: ___` relationship on your models to avoid cases where Noticed Events or Notifications are left lingering when your models are destroyed. In the case that they are or data becomes mis-matched, you’ll likely run into deserialization issues. That may be globally alleviated with the following snippet, but use with caution.
@@ -611,4 +619,3 @@ DATABASE_URL=postgres://127.0.0.1/noticed_test rails test
 
 ## 📝 License
 The gem is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).
-
diff --git a/UPGRADE.md b/UPGRADE.md
index 7684369d..8442582c 100644
--- a/UPGRADE.md
+++ b/UPGRADE.md
@@ -290,40 +290,41 @@ Options for delivery methods have been renamed for clarity and consistency.
 
 #### ActionCable
 
-The `format` option has been renamed to `message`.
-The `Noticed::NotificationChannel` has been removed and an example channel is provided in the [ActionCable docs](docs/delivery_methods/action_cable.md).
+- The `format` option has been renamed to `message`.
+- The `Noticed::NotificationChannel` has been removed and an example channel is provided in the [ActionCable docs](docs/delivery_methods/action_cable.md).
 
 #### Email Delivery Method
 
-`method` is now a required option. Previously, it was inferred from the notification name but we've decided it would be better to be explicit.
+- `method` is now a required option. Previously, it was inferred from the notification name but we've decided it would be better to be explicit.
 
 #### FCM
 
-The `format` option has been renamed to `json`.
-The `device_tokens` option is now required and should return an Array of device tokens.
-The `invalid_token` option replaces the `cleanup_device_tokens` method for handling invalid/expired tokens.
+- The `format` option has been renamed to `json`.
+- The `device_tokens` option is now required and should return an Array of device tokens.
+- The `invalid_token` option replaces the `cleanup_device_tokens` method for handling invalid/expired tokens.
+- We no longer wrap the json payload in the `message{}` key. This means we are more compatible with the FCM docs and any future changes that Google make.
 
 #### iOS
 
-The `cert_path` option has been renamed to `apns_key` and should be given the key and not a path.
-The `device_tokens` option is now required and should return an Array of device tokens.
-The `invalid_token` option replaces the `cleanup_device_tokens` method for handling invalid/expired tokens.
+- The `cert_path` option has been renamed to `apns_key` and should be given the key and not a path.
+- The `device_tokens` option is now required and should return an Array of device tokens.
+- The `invalid_token` option replaces the `cleanup_device_tokens` method for handling invalid/expired tokens.
 
 #### Microsoft Teams
 
-The `format` option has been renamed to `json`.
+- The `format` option has been renamed to `json`.
 
 #### Slack
 
-The `format` option has been renamed to `json`.
-The `url` option now defaults to `"https://slack.com/api/chat.postMessage` instead of `Rails.application.credentials.dig(:slack, :notification_url)`
+- The `format` option has been renamed to `json`.
+- The `url` option now defaults to `"https://slack.com/api/chat.postMessage` instead of `Rails.application.credentials.dig(:slack, :notification_url)`
 
 #### Twilio Messaging
 
-Twilio has been renamed to `:twilio_messaging` to make room for `:twilio_voice` and other services they may provide in the future.
-The `format` option has been renamed to `json`.
+- Twilio has been renamed to `:twilio_messaging` to make room for `:twilio_voice` and other services they may provide in the future.
+- The `format` option has been renamed to `json`.
 
 #### Vonage SMS
 
-Vonage has been renamed to `:vonage_sms` to make room for other Vonage services in the future.
-The `format` option has been renamed to `json` and is now required.
+- Vonage has been renamed to `:vonage_sms` to make room for other Vonage services in the future.
+- The `format` option has been renamed to `json` and is now required.
diff --git a/app/models/concerns/noticed/deliverable.rb b/app/models/concerns/noticed/deliverable.rb
index e0a385ba..05621c07 100644
--- a/app/models/concerns/noticed/deliverable.rb
+++ b/app/models/concerns/noticed/deliverable.rb
@@ -103,7 +103,7 @@ def validate!
 
     def validate_params!
       required_param_names.each do |param_name|
-        raise ValidationError, "Param `#{param_name}` is required for #{self.class.name}." unless params[param_name].present?
+        raise ValidationError, "Param `#{param_name}` is required for #{self.class.name}." unless params.has_key?(param_name)
       end
     end
 
diff --git a/docs/delivery_methods/fcm.md b/docs/delivery_methods/fcm.md
index 759a1bdd..09aa5af5 100644
--- a/docs/delivery_methods/fcm.md
+++ b/docs/delivery_methods/fcm.md
@@ -26,51 +26,92 @@ See the below instructions on where to store this information within your applic
 class CommentNotification
   deliver_by :fcm do |config|
     config.credentials = Rails.root.join("config/certs/fcm.json")
+    config.device_tokens = ->(recipient) { recipient.notification_tokens.where(platform: "fcm").pluck(:token) }
     config.json = ->(device_token) {
       {
-        token: device_token,
-        notification: {
-          title: "Test Title",
-          body: "Test body"
+        message: {
+          token: device_token,
+          notification: {
+            title: "Test Title",
+            body: "Test body"
+          }
         }
       }
     }
+    config.if = ->(recipient) { recipient.android_notifications? }
   end
 end
 ```
 
 ## Options
 
-* `json`
-  Customize the Firebase Cloud Messaging notification object. This can be a Lambda or Symbol of a method name on the notifier. The callable object will be given the device token as an argument.
+### `json`
+Customize the Firebase Cloud Messaging notification object. This can be a Lambda or Symbol of a method name on the notifier. 
+  
+The callable object will be given the device token as an argument.
 
-* `credentials`
+There are lots of options of now to structure a FCM notification message. See https://firebase.google.com/docs/cloud-messaging/concept-options for more details.
+
+### `credentials`
 The location of your Firebase Cloud Messaging credentials.
-- When a String object: `deliver_by :fcm, credentials: "config/credentials/fcm.json"`
-  * Interally, this string is passed to `Rails.root.join()` as an argument so there is no need to do this beforehand.
-- When a Pathname object: `deliver_by :fcm, credentials: Rails.root.join("config/credentials/fcm.json")`
-   * The Pathname object can point to any location where you are storing your credentials.
-- When a Hash object: `deliver_by :fcm, credentials: credentials_hash`
-    ```ruby
-        credentials_hash = {
-          "type": "service_account",
-          "project_id": "test-project-1234",
-          "private_key_id": ...,
-          etc.....
-        }
-    ```
 
-  * A Hash which contains your credentials
-- When a Symbol: `deliver_by :fcm, credentials: :fcm_credentials, format: :format_notification`
-    ```ruby
-        def fcm_credentials
-          Rails.root.join("config/certs/fcm.json")
-        end
-    ```
+#### When a String Object
+
+Internally, this string is passed to `Rails.root.join()` as an argument so there is no need to do this beforehand.
+
+```ruby
+deliver_by :fcm do |config| 
+  config.credentials = "config/credentials/fcm.json"
+end
+```
+
+#### When a Pathname object
+
+The Pathname object can point to any location where you are storing your credentials.
+
+```ruby
+deliver_by :fcm do |config| 
+  config.credentials = Rails.root.join("config/credentials/fcm.json")
+end
+```
+
+#### When a Hash object
+
+A Hash which contains your credentials
+
+```ruby
+deliver_by :fcm do |config| 
+  config.credentials = credentials_hash 
+end
+
+credentials_hash = {
+  "type": "service_account",
+  "project_id": "test-project-1234",
+  "private_key_id": ...,
+  etc.....
+}
+```
+
+#### When a Symbol
+
+Points to a method which can return a Hash of your credentials, Pathname, or String to your credentials like the examples above. 
+
+We pass the notification object as an argument to the method. If you don't need to use it you can use the splat operator `(*)` to ignore it.
+
+```ruby
+deliver_by :fcm do |config| 
+  config.credentials = :fcm_credentials
+  config.json = :format_notification
+end
+
+def fcm_credentials(*)
+  Rails.root.join("config/certs/fcm.json")
+end
+```
 
-  * Points to a method which can return a Hash of your credentials, Pathname, or String to your credentials like the examples above.
+#### Otherwise
 
-Otherwise, if the credentials option is left out, it will look for your credentials in: `Rails.application.credentials.fcm`
+If the credentials option is left out, it will look for your credentials in: `Rails.application.credentials.fcm`
 
 ## Gathering Notification Tokens
 
diff --git a/lib/noticed.rb b/lib/noticed.rb
index c39d548d..444a34c2 100644
--- a/lib/noticed.rb
+++ b/lib/noticed.rb
@@ -39,6 +39,9 @@ module DeliveryMethods
     autoload :Webhook, "noticed/delivery_methods/webhook"
   end
 
+  mattr_accessor :parent_class
+  @@parent_class = "Noticed::ApplicationJob"
+
   class ValidationError < StandardError
   end
 
diff --git a/lib/noticed/delivery_method.rb b/lib/noticed/delivery_method.rb
index f84dc63e..5e7b7069 100644
--- a/lib/noticed/delivery_method.rb
+++ b/lib/noticed/delivery_method.rb
@@ -1,5 +1,5 @@
 module Noticed
-  class DeliveryMethod < ApplicationJob
+  class DeliveryMethod < Noticed.parent_class.constantize
     include ApiClient
     include RequiredOptions
 
diff --git a/lib/noticed/delivery_methods/fcm.rb b/lib/noticed/delivery_methods/fcm.rb
index ad166637..99ad60c1 100644
--- a/lib/noticed/delivery_methods/fcm.rb
+++ b/lib/noticed/delivery_methods/fcm.rb
@@ -14,7 +14,7 @@ def deliver
       def send_notification(device_token)
         post_request("https://fcm.googleapis.com/v1/projects/#{credentials[:project_id]}/messages:send",
           headers: {authorization: "Bearer #{access_token}"},
-          json: notification.instance_exec(device_token, &config[:json]))
+          json: format_notification(device_token))
       rescue Noticed::ResponseUnsuccessful => exception
         if exception.response.code == "404" && config[:invalid_token]
           notification.instance_exec(device_token, &config[:invalid_token])
@@ -23,6 +23,15 @@ def send_notification(device_token)
         end
       end
 
+      def format_notification(device_token)
+        method = config[:json]
+        if method.is_a?(Symbol) && event.respond_to?(method)
+          event.send(method, device_token)
+        else
+          notification.instance_exec(device_token, &method)
+        end
+      end
+
       def credentials
         @credentials ||= begin
           value = evaluate_option(:credentials)
diff --git a/test/delivery_methods/action_cable_test.rb b/test/delivery_methods/action_cable_test.rb
index 38c8b163..94551265 100644
--- a/test/delivery_methods/action_cable_test.rb
+++ b/test/delivery_methods/action_cable_test.rb
@@ -9,10 +9,10 @@ class ActionCableDeliveryMethodTest < ActiveSupport::TestCase
 
   test "sends websocket message" do
     user = users(:one)
-    channel = NotificationChannel.broadcasting_for(user)
+    channel = Noticed::NotificationChannel.broadcasting_for(user)
 
     set_config(
-      channel: "NotificationChannel",
+      channel: "Noticed::NotificationChannel",
       stream: user,
       message: {foo: :bar}
     )
diff --git a/test/dummy/app/channels/notification_channel.rb b/test/dummy/app/channels/notification_channel.rb
deleted file mode 100644
index 66cdb454..00000000
--- a/test/dummy/app/channels/notification_channel.rb
+++ /dev/null
@@ -1,9 +0,0 @@
-class NotificationChannel < ApplicationCable::Channel
-  def subscribed
-    stream_for current_user
-  end
-
-  def unsubscribed
-    stop_all_streams
-  end
-end