About us :
At FIS, our technology and our people are moving forward. We advance the way the world pays, banks and invests. We believe in building inclusive, diverse teams. Together, we innovate to help our colleagues, clients and communities succeed. If you’re ready to grow your career and make an impact in fintech, we have one question: Are you FIS?
About the Role
We are looking for an experienced Non-Functional Engineer to join a team developing backend payment-processing software for large international banks.
Our technology landscape includes legacy applications deployed on IBM WebSphere, modernized Java applications running on Open Liberty, and cloud-native applications deployed on Kubernetes. Our payment solutions are standardized around SWIFT messaging and must meet demanding requirements for performance, scalability, resilience, availability, and operational stability.
The Non-Functional Engineer will be responsible for designing, implementing, maintaining, and automating tests that validate the non-functional requirements of our software. You will work closely with architects, developers, DevOps engineers, and other stakeholders to identify bottlenecks, investigate failures, and improve the overall reliability and performance of the platform.
You will also support the analysis and resolution of non-functional issues reported by customers in production environments.
What You Will Be Doing-
- Define test approaches and test scenarios for non-functional requirements, including:
- Transaction throughput
- Network bandwidth and data volume
- Response times and latency
- Scalability
- Resilience and fault tolerance
- High availability and recovery
- Resource consumption
- Stability under sustained load
- Behaviour during infrastructure or dependency failures
- Create, maintain, and execute automated non-functional test suites for:
- Legacy Java applications running on IBM WebSphere
- Java applications deployed on Open Liberty
- Cloud-native applications running on Kubernetes
- Translate architectural and business requirements into measurable non-functional acceptance criteria.
- Develop realistic workload models that represent payment-processing patterns used by large banks.
- Validate application behaviour under normal, peak, stress, endurance, and failure conditions.
- Automate the provisioning, execution, monitoring, and reporting of non-functional tests.
- Integrate non-functional testing into Maven and Jenkins-based CI/CD pipelines.
- Analyse application, infrastructure, JVM, network, and container-level metrics to identify bottlenecks and abnormal behaviour.
- Use logs, metrics, traces, and test results to perform root-cause analysis.
- Work with architects and developers to diagnose and resolve issues identified during non-functional testing.
- Reproduce and investigate performance, capacity, resilience, and stability issues reported by customers.
- Provide clear test reports containing:
- Test objectives and assumptions
- Environment and configuration details
- Workload characteristics
- Results and observations
- Identified bottlenecks
- Risks and limitations
- Recommended corrective actions
- Establish performance baselines and detect regressions between software versions.
- Contribute to standards, reusable test components, automation frameworks, and engineering best practices for non-functional validation.
- Support capacity planning and provide evidence-based recommendations for application and infrastructure sizing.
Required Qualifications
- Strong experience with non-functional, performance, load, stress, scalability, or resilience testing.
- Experience designing automated tests for high-volume backend or distributed systems.
- Strong knowledge of Java applications and the Java Virtual Machine, including:
- JVM memory management
- Garbage collection
- Threading and concurrency
- Connection pools
- Heap and thread dump analysis
- CPU and memory profiling
- Experience testing applications deployed on one or more Java application servers, preferably:
- IBM WebSphere Application Server
- Open Liberty
- Good understanding of cloud-native and containerized application architectures.
- Practical experience with Kubernetes, preferably standard or vanilla Kubernetes distributions.
- Experience with CI/CD and build automation tools, particularly:
- Experience using observability and analysis platforms such as:
- Grafana
- Kibana
- Elasticsearch
- Ability to analyse application logs, infrastructure metrics, JVM statistics, and distributed-system behaviour.
- Good scripting or programming skills for test and workflow automation.
- Good understanding of networking concepts relevant to non-functional testing, including:
- Bandwidth
- Latency
- TCP connections
- Load balancing
- Timeouts
- Retries
- Network saturation
- Experience working with relational databases, messaging systems, REST APIs, or other backend integrations.
- Strong analytical and problem-solving skills.
Preferred Skills
- Knowledge of OpenTelemetry, including metrics, logs, distributed traces, instrumentation, and context propagation.
- Experience with payment-processing systems, financial services, or large banking environments.
- Knowledge of SWIFT messaging and payment standards.
- Experience testing high-throughput, business-critical, or highly available systems.
- Experience with resilience and failure testing, including:
- Pod or process termination
- Network disruption
- Dependency unavailability
- Database or messaging failures
- Resource exhaustion
- Rolling upgrades and failover
- Experience with performance-testing tools such as JMeter, Gatling, NeoLoad, k6, or equivalent platforms.
- Experience with infrastructure or environment automation.
- Knowledge of Kubernetes observability, resource management, autoscaling, health checks, and scheduling.
- Experience with JVM profiling and diagnostic tools.
- Familiarity with site reliability engineering, capacity engineering, or chaos-engineering practices.
Collaboration and Stakeholder Responsibilities
The Non-Functional Engineer will work closely with:
- Solution and application architects to define measurable non-functional requirements.
- Developers to identify bottlenecks and implement corrective actions.
- DevOps and platform engineers to create representative and repeatable test environments.
- Test engineers to align functional and non-functional validation.
- Support teams to investigate customer-reported issues.
- Product and delivery stakeholders to communicate risks, results, and release readiness.
- The engineer is expected to communicate technical findings clearly and to turn test results into practical recommendations for both development teams and stakeholders.
- Approaches performance and resilience testing as an engineering discipline rather than a one-time test activity.
- Is comfortable working across application code, JVM behaviour, infrastructure, Kubernetes, networking, and observability.
- Can independently investigate complex problems involving multiple components.
- Values automation, repeatability, measurable acceptance criteria, and evidence-based conclusions.
- Can collaborate constructively with developers and architects to resolve issues rather than only report them.
- Understands the quality and reliability expectations associated with software used by large financial institutions.
- Can work effectively in an environment containing legacy, modernized, and cloud-native technology stacks.
Qualifications
- Bachelor’s or master’s degree in computer science, software engineering, information technology, or equivalent professional experience.
- Several years of experience in non-functional testing, performance engineering, software engineering, DevOps, site reliability engineering, or a related technical role.
- Professional working proficiency in English.
What We Offer you
At FIS, you can grow your career as far as you want to take it. Here’s what else we offer:
Opportunities to make an impact in fintech
Personal and professional learning
Inclusive, diverse work environment
Resources to give back to your community
Competitive salary and benefits
