diff --git a/Gemfile.lock b/Gemfile.lock
index daa0fdc..89c5f71 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    lockstep_rails (0.3.79)
+    lockstep_rails (0.3.80)
       rails
 
 GEM
diff --git a/app/concepts/lockstep/client.rb b/app/concepts/lockstep/client.rb
index 11dc51e..b45cb0c 100644
--- a/app/concepts/lockstep/client.rb
+++ b/app/concepts/lockstep/client.rb
@@ -37,6 +37,20 @@ def internal_service_key
       RequestStore.store[:internal_service_key]
     end
 
+    def self.set_x_group_key(x_group_key)
+      RequestStore.store[:lockstep_x_group_key] = x_group_key
+      true
+    end
+
+    def self.x_group_key
+      RequestStore.store[:lockstep_x_group_key]
+    end
+
+    def self.set_m2m_token(token)
+      # this method can be ommitted and we can use directly `set_bearer_token`
+      set_bearer_token(token)
+    end
+
     ##
     # Construct a new Lockstep API client targeting the specified server.
     #
@@ -81,6 +95,10 @@ def api_key
       self.class.api_key
     end
 
+    def x_group_key
+      self.class.x_group_key
+    end
+
     ##
     # Configure this API to use an application name
     #
@@ -139,6 +157,10 @@ def request(method, path, body, params)
         request["Authorization"] = 'Bearer ' + bearer_token
       end
 
+      if x_group_key != nil
+        request["X-Group-Key"] = x_group_key
+      end
+
       # Send the request
       http.request(request)
     end
diff --git a/lib/lockstep_rails/version.rb b/lib/lockstep_rails/version.rb
index e0d558e..ba5b381 100644
--- a/lib/lockstep_rails/version.rb
+++ b/lib/lockstep_rails/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module LockstepRails
-  VERSION = '0.3.79'
+  VERSION = '0.3.80'
 end