diff --git a/Gemfile b/Gemfile
index c807c4dec..e3c350e43 100644
--- a/Gemfile
+++ b/Gemfile
@@ -163,6 +163,9 @@ group :development, :test do
 
   # mock http calls
   gem 'webmock'
+
+  # record and replay TCP transactions
+  gem 'tcr'
 end
 
 # Want to extend Zammad with additional gems?
diff --git a/Gemfile.lock b/Gemfile.lock
index ef59f768d..2d1a3dbfc 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -421,6 +421,7 @@ GEM
       activesupport (>= 4.0)
       sprockets (>= 3.0.0)
     sqlite3 (1.3.13)
+    tcr (0.2.0)
     telegramAPI (1.4.2)
       rest-client (~> 2.0, >= 2.0.2)
     telephone_number (1.3.0)
@@ -555,6 +556,7 @@ DEPENDENCIES
   slack-notifier
   sprockets
   sqlite3
+  tcr
   telegramAPI
   telephone_number
   test-unit