Java & Networking Engineer

About the role

The Qualysoft Group invites applications for a specialized technical role within its Financial Services division, representing a focused opportunity for engineers who thrive in precision-critical environments. Founded in 1999 in Vienna, the company operates as a manufacturer-independent IT consulting and services provider with a global footprint. Its core mission is to enhance the competitiveness and economic efficiency of international clients through innovative technological solutions that drive tangible business value. The group serves a diverse range of high-stakes sectors, including financial services providers, telecommunications companies, the automotive industry, and energy service providers that demand absolute reliability. This specific opening is one of over 400 roles distributed across 6 specialized subsidiaries dedicated to delivering state-of-the-art solutions to a global clientele.

This role is integral to the infrastructure that underpins high-frequency trading environments where milliseconds can define commercial success. The successful candidate will own the complete lifecycle of specific financial features, transforming abstract requirements into robust, production-grade components. This encompasses designing data intake mechanisms capable of absorbing massive market data streams and assembling resilient services that maintain integrity under duress. A core part of the position involves examining deployment outcomes and performance telemetry to ensure that systems meet stringent operational standards. The role necessitates coordination of release sequences in careful alignment with partner roadmaps to synchronize delivery timelines. Daily duties involve mentoring junior team members to elevate the entire engineering bench and making architectural refinements that compound in value over time. Ultimately, a key focus is ensuring the stability, performance, and security of critical market-facing systems that handle significant financial volume.

What you'll do

• Architect and manage the intricate flow of information within complex, multi-venue trading ecosystems.
• Orchestrate message flows between diverse trading systems and high-performance market data handlers with deterministic precision.
• Construct high-throughput Java microservices that communicate bidirectionally with FIX engines and direct market access gateways.
• Examine real-time latency metrics and perform deep tuning of thread pools and network buffers to optimize order processing velocity.
• Collaborate closely with trading desk engineers to validate FIX session behavior, ensuring absolute accuracy in message sequencing and integrity.
• Ship incremental improvements behind sophisticated feature flags while maintaining comprehensive rollback strategies to mitigate risk.
• Partner with infrastructure and network teams to harden network paths, optimize routing, and define firewall rules that meet strict regulatory standards.
• Review configuration templates for exchange connectivity, settlement links, and failover mechanisms to guarantee robustness and compliance.
• Integrate specialized adapters that normalize disparate market data formats across different trading venues and communication protocols.
• Analyze system logs and performance traces to identify bottlenecks and implement corrective actions that improve system resilience.
• Contribute to the definition and enforcement of coding standards and architectural best practices for the financial services line of business.
• Participate in on-call rotations to provide rapid response to production incidents and support continuous availability targets.
• Mentor and guide junior developers through code reviews, design discussions, and technical documentation to foster a culture of excellence.
• Evaluate emerging technologies and tools that could provide a competitive edge in low-latency financial applications.
• Ensure all deliverables align with the strict security, compliance, and operational requirements of the financial sector.

Requirements

• Demonstrate mastery of Java and concurrent network programming, with a deep understanding of the Java Memory Model and JVM internals.
• Possess hands-on work with FIX protocol implementations, including session management, message validation, and connectivity to exchange gateways.
• Show a solid understanding of low-latency networking concepts, TCP tuning practices, and the impact of network topology on performance.
• Have experience managing Kafka clusters, including configuration, scaling, and message durability guarantees for critical event streams.
• Exhibit practical skills in Linux administration within data center environments, including shell scripting, process management, and performance monitoring.
• Display the ability to navigate complex CI pipelines and container-based deployment workflows using industry-standard tools.
• Hold a strong grasp of software design principles, design patterns, and the ability to write clean, maintainable, and testable code.
• Bring a proven track record of debugging complex distributed systems and resolving issues under production pressure.

Nice to have

Experience with exchange co-location setups and microwave links is valued, as this background provides a distinct advantage for optimizing performance in real-world trading scenarios where physical distance impacts latency.

Practical notes

This position is based in Budapest and operates on a full-time engagement basis. The compensation package is specified as 4500 EUR gross monthly.