Senior Java Performance Engineer

Project overview

This contract role supports the Portfolio Performance Reporting team, which builds and runs platforms for portfolio returns, asset allocation, and holdings for financial advisors, operations teams, and clients. The core requirements are Java 17/21 with Spring Boot and framework upgrades, SQL Server/Azure SQL performance tuning, and hands-on distributed or stream processing. DB2 and mainframe migration, Azure Kubernetes Service and Helm, Entra ID, SCA remediation, and wealth-management experience are listed as advantages; Agile, TDD, and DevOps practices are also expected.

The structured input gives an experience band of 8–10 years, while the description states a minimum of 18 years of hands-on Java experience, so this requirement needs reconciliation. The role is based in Krakow and is contract; work mode is not specified.

Responsibilities

• Develop and maintain Java 21 / Spring Boot batch and microservices for the KPS and XPOS platforms, including framework and dependency upgrades.
• Operate, tune and troubleshoot our Apache Storm-based XPOS processing cluster, including worker balancing, restarts and alert tuning.
• Analyze and optimize SQL performance on Azure SQL Hyperscale, including execution plans, indexing, query tuning and high-availability replica behavior, working directly with Microsoft engineering and support.
• Migrate mainframe batch jobs and DB2 data flows to Azure (Hyperscale and Azure messaging), as part of the CPOS / XPOS modernization program.
• Monitor the nightly performance batch against its service levels, lead root cause analysis of production incidents, and remediate open-source security findings (Nexus IQ / SCA) with the right risk sign-off.
• Degree level education; preferably Computer Science (bachelor's or master's degree).
• Minimum of 18 years of hands-on Java development experience, ideally within banking or financial services.
• Strong proficiency in Java (17/21) and Spring Boot, including large framework upgrades ( must have ).
• Proven experience tuning SQL Server / Azure SQL, ideally Hyperscale, including reading execution plans, resolving plan regressions and CPU bottlenecks ( must have ).
• Hands-on experience with distributed or stream processing such as Apache Storm, Kafka Streams or Flink ( must have ).
• Experience with DB2 and with reading or migrating mainframe batch jobs ( added advantage ).
• Experience with Azure Kubernetes Service, Helm and Azure AD / Entra ID integration ( added advantage ).

Requirements

• Java 17/21 and Spring Boot development, including framework and dependency upgrades
• SQL Server/Azure SQL performance tuning, including execution plans, indexing, plan regressions, and CPU bottlenecks
• Hands-on distributed or stream processing experience with Apache Storm, Kafka Streams, or Flink

Project details

• Start: flexible
• Remote: hybrid
• Location: Poland, PL