Software Development Engineer in Test (SDET)

Calling all innovators – find your future at Fiserv. We’re Fiserv, a global leader in Fintech and payments, and we move money and information in a way that moves the world. We connect financial institutions, corporations, merchants, and consumers to one another millions of times a day – quickly, reliably, and securely. Any time you swipe your credit card, pay through a mobile app, or withdraw money from the bank, we’re involved. If you want to make an impact on a global scale, come make a difference at Fiserv. Job Title Software Development Engineer in Test (SDET) What does a successful Software Development Engineer (SDET) do? We are modernising a large-scale payment acquiring platform, replacing a monolithic batch processing system with event-driven microservices on Cloud. The platform processes millions of transactions daily for institutions globally, covering the full acquiring lifecycle. The modernisation spans five independent processing domains, each with its own engineering team. Migration is incremental, with legacy and new systems running in parallel during the transition. As a Software Development Engineer in Test (SDET) you will design, build, and maintain the automated testing frameworks and quality engineering capabilities for the new platform. This role bridges software development and quality assurance — you will write production-grade test code, build testing infrastructure, and embed quality into every stage of the delivery pipeline. This will be roughly 20% strategy and test design, 80% hands-on — building frameworks, writing test code, integrating with CI/CD pipelines, analysing failures, and collaborating with development teams to shift quality left. What you will do: Test Framework Architecture & Development Design, build, and maintain scalable automation frameworks for API, event-driven, and end-to-end testing across the microservices platform. Develop reusable test libraries, utilities, and abstractions that domain teams can consume to accelerate their own test development. Implement contract testing (consumer-driven contracts) to validate API and event schema compatibility across independently deployed services. Build test data management capabilities: synthetic data generation, seeding pipelines, and data virtualisation to enable isolated, repeatable test execution. Functional & Integration Test Automation Write and maintain automated test suites covering REST APIs, Kafka event flows, database operations, and cross-domain integration scenarios. Implement BDD/TDD test patterns aligned with acceptance criteria, working closely with developers and product owners. Design and automate complex end-to-end transaction flows across the acquiring lifecycle (capture, pricing, clearing, funding, disputes). Validate schema evolution and backward compatibility across Avro schemas and Schema Registry. Performance & Resilience Testing Design and develop performance test scripts and scenarios using appropriate tooling (e.g. Gatling, k6, JMeter) targeting REST APIs, Kafka producers/consumers, and database operations. Execute load, stress, soak, and spike tests across environments on AWS EKS, analysing results against defined SLIs/SLOs. Test system behaviour under failure conditions: pod evictions, broker unavailability, database failover, network partitions, and resource exhaustion. Validate back-pressure, retry, and circuit-breaker behaviour across the Kafka event pipeline under sustained load. CI/CD Integration & Quality Gates Integrate automated test suites into GitLab CI pipelines as quality gates — unit, integration, contract, and performance tests running at appropriate stages. Build automated result analysis with clear pass/fail criteria, trend tracking, and regression detection. Implement test parallelisation and optimisation strategies to keep pipeline feedback loops fast. Contribute to the ArgoCD GitOps workflow to ensure test environments are consistently provisioned and reproducible. Observability & Analysis Analyse test failures and production incidents using Dynatrace (APM/tracing), Micrometer/Prometheus metrics, and Splunk logs to identify root causes. Build quality dashboards and metrics reporting: test coverage, pass rates, flakiness trends, performance baselines, and defect escape rates. Produce actionable analysis for engineering teams — not just results, but root-cause insights and recommendations. Track performance trends across releases to detect regressions early and validate the impact of optimisation work. Collaboration & Quality Advocacy Embed quality earlier in the lifecycle: pair with engineers on TDD/BDD, contract tests, schema validation, and testability improvements. Partner with SRE/Platform teams on non-functional requirements: security testing, compliance (PCI, PSD2), and environment management. Participate in design reviews to advocate for testability, observability, and failure-mode coverage. Coach domain teams on automation best practices, shift-left testing, and effective use of the shared test frameworks. Leverage AI-assisted tooling to generate test scripts, analyse failures, and accelerate root-cause analysis. What you will need to have: Software development skills — strong programming ability in Java (or Kotlin/similar JVM language). You write production-quality code with proper design patterns, error handling, and maintainability. Test automation frameworks — hands-on experience building and maintaining automation frameworks (not just writing scripts within an existing framework). Experience with tools such as JUnit 5, REST Assured, Cucumber, or equivalent. Distributed systems testing — experience testing microservices architectures with asynchronous messaging (Kafka or equivalent), understanding how to validate eventual consistency, event ordering, and end-to-end data flows. API testing — deep experience with REST API testing including contract testing, schema validation, and integration testing across multiple services. CI/CD integration — experience embedding automated tests into pipelines (GitLab CI, Jenkins, or equivalent) with quality gates, parallel execution, and automated reporting. Performance testing — practical experience with at least one load testing tool (Gatling, k6, JMeter, or equivalent) and ability to design realistic load scenarios and analyse results. 6+ years in software quality engineering or test development roles with a strong development focus. What is nice to have: Financial services or payments — high-throughput transaction processing, batch processing pipelines, or similar volume-sensitive domains. Kubernetes and cloud-native — experience with EKS/GKE/AKS, containerised test execution, and understanding of cloud-native deployment patterns. Java/JVM performance — understanding of JVM profiling, garbage collection, thread pool management, and common performance anti-patterns. Observability platforms — experience with APM tools (Dynatrace, Datadog), metrics platforms (Prometheus/Grafana), and log aggregation (Splunk, ELK). Database testing — PostgreSQL or similar RDBMS, including data integrity validation, migration testing, and query performance analysis. Infrastructure as Code — Terraform, Helm charts, or similar for provisioning test infrastructure on-demand. Security testing — familiarity with SAST/DAST tools (Fortify, WebInspect, OWASP ZAP) and compliance automation. AI-assisted testing — experience with AI copilots and tooling for test generation, maintenance, and failure analysis. Contract testing — Pact or similar consumer-driven contract testing frameworks. #LI-1IB Thank you for considering employment with Fiserv. Please: Apply using your legal name Complete the step-by-step profile and attach your resume (either is acceptable, both are preferable). Our commitment to Diversity and Inclusion: Fiserv is proud to be an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, national or