Senior Java Performance Architect – Hybrid (Poland)

FIS; Warszawa; Hybrid; PLN 176,000 - 281,000; Full time

Benefits offered by this job

Impact in fintech

Learning opportunities

Inclusive environment

Community involvement

Competitive compensation

Job summary

FIS is seeking an experienced Software Architect Lead for Non-Functional Engineering (NFE) in Poland (hybrid). The role focuses on performance of large-scale Java systems, profiling, tuning, and leadership in load testing and optimization.

You will work with the NFE team to profile, measure, and prove optimisations that improve throughput, latency and cost, while guiding code-level improvements and architectural decisions.

Qualifications

• Substantial experience as a performance architect or senior performance engineer, optimising large-scale, high-throughput Java systems running in production.
• Deep, hands-on expertise in Java profiling tools to isolate CPU, memory, lock and I/O bottlenecks.
• Proven ability to analyse thread dumps and reason rigorously about concurrency, identifying deadlocks, contention and thread starvation.
• Strong command of JVM garbage collection internals with real experience interpreting GC logs and tuning heap sizing.
• Confidence reading database execution plans and tuning SQL, indexes and schema design to eliminate data-layer bottlenecks.

Responsibilities

• Profile Java applications end to end across CPU, memory, threads and I/O to isolate hot paths.
• Analyse thread dumps to diagnose lock contention and reshape the concurrency model.
• Own garbage collection analysis and JVM tuning to reduce pause times and stabilize latency under load.
• Read database execution plans to tune expensive SQL and indexing strategies.
• Work directly in the codebase to propose, implement and validate code-level optimisations.
• Design and lead load, stress, soak and failover campaigns and drive performance investigations.

Skills

Java profiling

Thread dumps analysis

GC tuning

DB plan reading

Developer mindset

Tools

Java Flight Recorder

async-profiler

JProfiler

YourKit

Oracle

PostgreSQL

Job description

FIS is seeking an experienced Software Architect Lead for Non-Functional Engineering (NFE) in Poland (hybrid). The role focuses on performance of large-scale Java systems, profiling, tuning, and leadership in load testing and optimization.

You will work with the NFE team to profile, measure, and prove optimisations that improve throughput, latency and cost, while guiding code-level improvements and architectural decisions.