Senior Java Software Engineer - #1697945

Senior Java Engineer – Core Java, Algo, Distributed Systems

Location: Belfast – 2/3 days per week needs to be possible (only considering candidates in NI)

Type: Contract

Industry: Investment Banking

Duration: ASAP – long term (12 months to start with extensions)

We’re seeking Senior / Lead Java Engineers to join a team building high-performance systems that support trading across Equity Swaps, Delta One, and Prime Brokerage. While low-latency expertise is not essential, a deep command of Core Java and algorithmic/data structure proficiency is critical to succeed in this complex and performance-sensitive environment.

Key Responsibilities:

• Design and enhance trading engines for derivatives and structured financial products.


• Build scalable systems to support high-volume operations (100s of TBs of data).


• Refactor and decouple legacy components, with a focus on MongoDB and modern relational DBs like PostgreSQL.


• Drive cloud readiness, adopt microservices architecture, and contribute to distributed system designs.


• Lead database migrations from legacy systems (e.g., Sybase, DB2) to modern platforms.

Required Skills:

• Strong Core Java expertise, with a focus on performance tuning and optimisation.


• Solid understanding of algorithms, data structures, and concurrent distributed environments.


• Proven experience with MongoDB and relational databases (e.g., PostgreSQL).


• Familiarity with service-oriented architecture, cloud platforms, and containerised environments.

Nice to Have:

• Experience with SingleStore, Sybase, DB2.


• Background in investment banking or financial services.

Join a high-calibre engineering team solving complex trading challenges with modern, scalable tech.