class EM::Synchrony::ActiveRecord::TransactionManager

def begin_transaction(options = {}) #:nodoc:
  transaction =
    if _current_stack.empty?
      ::ActiveRecord::ConnectionAdapters::RealTransaction.new(@connection, options)
    else
      ::ActiveRecord::ConnectionAdapters::SavepointTransaction.new(@connection, "active_record_#{Fiber.current.object_id}_#{open_transactions}", options)
    end
  _current_stack.push(transaction)
  transaction
end