diff --git a/server/app/interactors/authentication/signup.rb b/server/app/interactors/authentication/signup.rb
index 0a4c1f0c5..0aa986c33 100644
--- a/server/app/interactors/authentication/signup.rb
+++ b/server/app/interactors/authentication/signup.rb
@@ -8,13 +8,14 @@ def call
       ActiveRecord::Base.transaction do
         create_new_user
         create_organization_and_workspace
-
+        Rails.logger.info("[Signup] User email verification enabled: #{User.email_verification_enabled?}")
         user.skip_confirmation! unless User.email_verification_enabled?
 
         save_user
         if user.persisted?
           if User.email_verification_enabled?
             user.send_confirmation_instructions
+            Rails.logger.info("[Signup] Sending confirmation instructions to user: #{user.email}")
             context.message = "Signup successful! Please check your email to confirm your account."
           else
             context.message = "Signup successful!"
diff --git a/server/config/initializers/appsignal_active_job_nil_transaction.rb b/server/config/initializers/appsignal_active_job_nil_transaction.rb
new file mode 100644
index 000000000..e8643fa7f
--- /dev/null
+++ b/server/config/initializers/appsignal_active_job_nil_transaction.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+if defined?(Appsignal::Transaction)
+  Appsignal::Transaction.singleton_class.class_eval do
+    alias_method :create_without_string_id, :create
+
+    def create(id, namespace, request, options = {})
+      create_without_string_id(id.to_s, namespace, request, options)
+    end
+  end
+end
+
+Rails.application.config.to_prepare do
+  next unless defined?(Appsignal::Hooks::ActiveJobHook::ActiveJobClassInstrumentation)
+
+  safety_check = Module.new do
+    private
+
+    def transaction_set_error(transaction, exception)
+      return unless Appsignal.config[:activejob_report_errors] == "all"
+      return if transaction.nil?
+
+      transaction.set_error(exception)
+    end
+  end
+
+  Appsignal::Hooks::ActiveJobHook::ActiveJobClassInstrumentation.prepend(safety_check)
+end
diff --git a/server/spec/config/initializers/appsignal_active_job_nil_transaction_spec.rb b/server/spec/config/initializers/appsignal_active_job_nil_transaction_spec.rb
new file mode 100644
index 000000000..d24a91c9f
--- /dev/null
+++ b/server/spec/config/initializers/appsignal_active_job_nil_transaction_spec.rb
@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+RSpec.describe "Appsignal Active Job nil transaction fix (initializer)" do
+  before do
+    raise "Appsignal::Transaction not defined — is the gem loaded?" unless defined?(Appsignal::Transaction)
+  end
+
+  describe "Transaction.create converts id to String" do
+    it "passes a string id to the original create (fails if monkey patch is removed)" do
+      expect(Appsignal::Transaction).to respond_to(:create_without_string_id),
+                                        "Appsignal::Transaction does not respond to :create_without_string_id — " \
+                                          "the alias_method monkey patch in the initializer may have been removed"
+
+      allow(Appsignal::Transaction).to receive(:create_without_string_id).and_return(nil)
+
+      Appsignal::Transaction.create(123, :active_job, nil, {})
+
+      expect(Appsignal::Transaction).to have_received(:create_without_string_id)
+        .with("123", :active_job, nil, {})
+    end
+  end
+
+  describe "transaction_set_error with nil transaction" do
+    before do
+      unless defined?(Appsignal::Hooks::ActiveJobHook::ActiveJobClassInstrumentation)
+        raise "Appsignal::Hooks::ActiveJobHook::ActiveJobClassInstrumentation not defined " \
+              "— is the appsignal gem loaded?"
+      end
+    end
+
+    it "does not raise when transaction is nil (fails if monkey patch is removed)" do
+      instrumentation = Appsignal::Hooks::ActiveJobHook::ActiveJobClassInstrumentation
+      instance = Class.new { include instrumentation }.new
+
+      expect(instance.private_methods).to include(:transaction_set_error),
+                                          "Expected instance to have private method :transaction_set_error — " \
+                                            "the safety module may no longer be prepended in the initializer"
+
+      exception = StandardError.new("job error")
+      allow(Appsignal).to receive(:config).and_return({ activejob_report_errors: "all" })
+
+      expect { instance.send(:transaction_set_error, nil, exception) }.not_to raise_error
+    end
+  end
+end