Senior System Engineer

We are looking for a Resilience Engineer to ensure the reliability, scalability and robustness of our applications and platform. This role combines structured resiliency testing with chaos engineering principles to proactively uncover weaknesses and strengthen our product against failures.

Please note: we operate in a hybrid work model, so all candidates must be based in Kraków.

• Design and implement structured resiliency test patterns targeting Java services.
• Develop fault injection mechanisms (e.g., latency, exceptions, timeouts, resource exhaustion) to evaluate system behavior under failure conditions.
• Collaborate with SRE, Infrastructure and observability teams to enhance visibility, fault tolerance and recovery strategies.
• Implement self-healing mechanisms to improve system resilience and minimize downtime.
• Assist in defining and tracking resiliency KPIs, ensuring continuous monitoring and reporting of system performance under failure conditions.
• Take part in postmortems and provide actionable insights to strengthen application reliability.
• Partner with developers to establish and enforce best practices for fault tolerance and resilient architecture design

Required Qualifications:

• Strong experience in Java development.
• Deep understanding of JVM internals and failure modes.
• Experience with resilience libraries (e.g., Resilience4j).
• Familiarity with distributed systems and microservices failure patterns.
• Experience with testing frameworks (e.g., JUnit, Testcontainers, WireMock).
• Exposure to chaos engineering practices and tooling.
• Deep understanding of high-availability architectures, disaster recovery, and fault injection techniques.
• Familiarity with containerized environments (Docker, Kubernetes) and observability tools (preferably Prometheus & Grafana).
• Excellent analytical and troubleshooting skills.

Preferred Qualifications

• 5+ Years of engineering experience working in mission-critical, high-traffic environments.
• Cross-functional skill set spanning Systems Engineering and Quality Engineering.
• Exposure to Banking Domain and knowledge of high volume financials systems.
• Knowledge of automated remediation and self-healing architectures.
• Familiarity with network failure simulations and dependency resilience strategies.
• Hands-on expertise with cloud platforms - Preferably Azure