A securities processor includes non-volatile storage, a first-in-first-out queue maintained in the non-volatile storage to store events, a random access memory, and an order book maintained in the random access memory to store one or more events corresponding to quotes or outstanding orders related to a security. A matching process receives the events from the queue, determines whether the event can be matched with a contra-side event stored in the order book, and executes a transaction between the received event and a matched contra side event if a match is found.