Resiliency Test Engineer​/Performance Engineer​/Performance Tester

Job: Performance & Resiliency Test Engineer

Location: O'Fallon, MO
- Onsite

Work Model: Hybrid (4 Days Onsite, 1 Day Remote)- hybrid

Skills:
Performance Testing, Resiliency Testing, Failover Testing, Recovery Testing, TCP/IP, Packet Analysis, Load Testing, Soak Testing, Capacity Testing, Network Testing, Automation Testing, High Availability, ISO 8583, Active-Active Architecture.

We are seeking a highly skilled Performance & Resiliency Test Engineer to define and execute validation strategies for functional behavior, transaction integrity, performance, failover, recovery, monitoring, and production readiness of mission-critical systems. The ideal candidate will have expertise in performance engineering, resiliency testing, network protocols, and high-availability platforms.

• Develop and execute end-to-end test plans across lab, staging, and lower environments.
• Validate traffic movement and persistent TCP connections during maintenance and failure scenarios.
• Perform functional, integration, regression, negative, load, soak, capacity, failover, and recovery testing.
• Validate proxy bypass and return-to-legacy recovery procedures.
• Reproduce defects, analyze logs and packet captures, and support root cause analysis.
• Define test evidence, acceptance criteria, certification results, and operational readiness sign-offs.
• Collaborate with development, infrastructure, and operations teams to improve system resiliency.

• Performance Testing, Resiliency Testing, Network Testing, and Integration Testing.
• Strong TCP/IP networking and packet-level troubleshooting experience.
• Experience with automated test frameworks and failure-injection techniques.
• Hands-on experience with performance and capacity testing tools.
• Strong defect analysis, debugging, and technical documentation skills.
• Experience validating high-availability and failover architectures.

• Experience with Financial Messaging, ISO 8583, Payment Processing, Telecom, or other high-availability transaction platforms.
• Knowledge of Proxy, Load Balancer, Network Service, and Active-Active Failover testing.
• Exposure to distributed systems and high-throughput transaction environments.