IEX is on a mission to build fairer markets. Founded in 2012 and headquartered in New York City, IEX introduced its first trading venue in 2013 and launched it as a U.S. stock exchange in 2016. IEX believes that every investor has the right to trade on equal and fair terms, on every trade.

The exchange focuses on investor protection and performance by creating a market that aims to maximize shares traded at the best available price, decrease information leakage, eliminate informational disadvantages and persistent inefficiencies, and promote opportunities for natural interests to interact without unnecessary intermediation.

Design goals

  • Offer all exchange members a single, standardized, reliable and performant method of order entry into IEX
  • Reuse connectivity components for gateways to other exchanges and clearing entities
  • Connectivity components need to be recoverable, resilient, and avoid data loss to the maximum extent possible
  • Support detailed inspection and administration of the internal state of the connectivity components


  • EPAM FIX Antenna Java (FIX AJ) provided a rich and mature set of APIs for implementing a uniform, low-latency FIX connectivity layer with recovery and data loss avoidance characteristics
  • IEX created components using FIX AJ that seamlessly convert messages between FIX and IEX-binary representations
  • IEX created monitoring dashboards and administrative commands based on detailed information/control provided by the FIX AJ API

EPAM contributed various design suggestions, best integration approaches, and supported IEX during the buildup phase, with quick turnaround times for any requested changes.

Technologies and tools


The FIX connectivity components were successfully implemented and have been widely deployed over time to support thousands of FIX sessions in production. EPAM Systems continues to collaborate with IEX and provides post-implementation support.