diff --git a/lib/appsignal/hooks/sidekiq.rb b/lib/appsignal/hooks/sidekiq.rb
index <HASH>..<HASH> 100644
--- a/lib/appsignal/hooks/sidekiq.rb
+++ b/lib/appsignal/hooks/sidekiq.rb
@@ -22,10 +22,10 @@ module Appsignal
     class SidekiqPlugin
       include Appsignal::Hooks::Helpers
 
-      JOB_KEYS = Set.new(%w(
+      JOB_KEYS = %w(
         args backtrace class created_at enqueued_at error_backtrace error_class
         error_message failed_at jid retried_at retry wrapped
-      )).freeze
+      ).freeze
 
       def call(_worker, item, _queue)
         transaction = Appsignal::Transaction.create(
Remove Set usage (#<I>)

In PR #<I> the Sidekiq hook `job_keys` method was moved to the

`JOB_KEYS` constant. As its value is a `Set` instance the `set` library

is required to be loaded beforehand. This was loaded by Sidekiq in

<URL>

```