Monkey patch for delayed_job to to ignore Delayed::DeserializationError when a job is run against a deleted active record model.

delayed_job_monkey_patch

# config/initializers/delayed_job_config.rb
module Delayed
  module Backend
    module Base

      def invoke_job_with_deserialize_catch
        begin
          invoke_job_without_deserialize_catch
        rescue Delayed::DeserializationError
          Rails.logger.error "Record was deleted when job ran!"
        end
      end

      alias_method_chain :invoke_job, :deserialize_catch

    end
  end
end