Java Low Latency Connectivity Engineer

Java Low Latency Connectivity Developer London | 4 Days Office, Victoria | Crytpo Exchange Connectivity / FIX A specialist electronic trading firm is seeking a Java Low Latency Connectivity Developer to join a highly technical, performance-driven engineering team. The business operates automated trading strategies across both traditional financial markets and crypto venues. Technology is central to performance, and connectivity to exchanges is a core competitive edge. This is a hands-on role within a small, experienced team where engineers work directly on systems that impact live trading outcomes. The Role You will be responsible for designing, building and optimising exchange connectivity across multiple venues, with a strong focus on crypto markets. Key responsibilities include: * Developing ultra-low latency Java components * Managing FIX protocol sessions and order flow * Integrating and optimising crypto exchange APIs using REST and WebSocket * Handling real-time JSON market data feeds * Improving performance and reducing latency across exchange connections * Supporting and enhancing live trading systems Each exchange has its own architecture, API behaviour and performance characteristics. You will play a key role in ensuring reliable, high-performance connectivity across them. What We Are Looking For * Strong core Java expertise * Experience in low latency or performance-critical systems * Solid understanding of FIX protocol (session and application layers) * Direct experience connecting to trading venues or exchanges * Hands-on experience integrating with crypto exchanges * Strong understanding of REST and WebSocket APIs in real-time environments * Experience working in Linux-based production systems Exposure to high-performance libraries such as Aeron, Agrona, SBE or Artio is advantageous. The Environment * Small, collaborative engineering team * Flat structure with real ownership * Office-based in Victoria, London (4 days per week) * 24/7 automated trading systems * Occasional out-of-hours support rotation This role is well suited to engineers who enjoy working close to the market, solving hard performance problems, and taking responsibility for exchange connectivity in a fast-moving environment