NoMethodError: undefined method 'extend!' for nil (NoMethodError)

[ops-handler]

Error

undefined method 'extend!' for nil (NoMethodError)

    lock.extend!
        ^^^^^^^^

Stack trace

app/controllers/api/mentoring/requests_controller.rb:35 in extend_lock
action_controller/metal/basic_implicit_render.rb:6 in send_action
abstract_controller/base.rb:224 in process_action
action_controller/metal/rendering.rb:165 in process_action
abstract_controller/callbacks.rb:259 in block in AbstractController::Callbacks#process_action
active_support/callbacks.rb:121 in block in ActiveSupport::Callbacks#run_callbacks
i18n.rb:353 in with_locale
app/controllers/application_controller.rb:57 in switch_locale!
active_support/callbacks.rb:130 in block in ActiveSupport::Callbacks#run_callbacks
turbo-rails.rb:24 in Turbo.with_request_id

Tracking Details

• Project: exercism-rails
• Sentry: NoMethodError: undefined method 'extend!' for nil (NoMethodError)
• Culprit: API::Mentoring::RequestsController#extend_lock
• First seen: Apr 18, 2026