Everbread Limited | 345 followers on LinkedIn. EVERBREAD has developed a proprietary pricing and shopping engine, HAYSTACK, that allows airlines, online travel agencies, and travel consortia to offer cheaper fares on a greater number of flights. HAYSTACK combines multiple sources of airline fares (ATPCO, IATA, OAG, SITA, Low-Cost Carriers, private fares). Drawing on different industry data sources, HAYSTACK returns a broader range of flight options to B2B customers and through them, to the end consumer.