diff --git a/lib/application_insights/channel/sender_base.rb b/lib/application_insights/channel/sender_base.rb
index 9814fd0..39c60c7 100644
--- a/lib/application_insights/channel/sender_base.rb
+++ b/lib/application_insights/channel/sender_base.rb
@@ -1,5 +1,6 @@
 require 'json'
 require 'net/http'
+require 'openssl'
 require 'stringio'
 require 'zlib'