Performance Tester

Role: Performance Tester Work Model & Location: Hybrid - 2-3 day onsite in Reading Duration: 6 Months+ The role involves validating system scalability, response time, throughput, and stability under real-world and peak load conditions to ensure business-critical billing processes operate without performance degradation. Our client, working with a British multinational energy company who are a constituent of the FTSE 100 Index are seeking an experienced Performance Tester to support the Keystone transformation program, focusing on non-functional validation of billing systems, integrations, and dual run operations. Your responsibilities: * Analyse performance testing requirements including user load, throughput, transaction volumes, and usage patterns * Prepare Performance Test Strategy and Test Plan aligned to program milestones * Design and develop performance test scripts using JMeter and/or LoadRunner * Execute load, stress, endurance, and volume testing * Monitor application performance using tools such as Dynatrace, AppDynamics, or Azure Monitor * Analyse results and identify bottlenecks and system limitations * Prepare performance reports and tuning recommendations * Manage performance defects through to resolution * Support dual run validation ensuring stable billing operations * Validate high-volume transactions across multiple integrated systems. Your Profile Essential skills/knowledge/experience: * 5–10 years of experience in Performance Testing / Non-functional Testing * Strong experience with JMeter, LoadRunner, or NeoLoad * Understanding of workload modelling and performance engineering concepts * Experience in Agile / DevOps environments * Experience in utilities or billing systems is highly desirable Key Deliverables * Performance Test Strategy and Plan * Test Scripts and Workload Models * Execution Reports and Dashboards * Bottleneck Analysis and RCA * Performance Test Summary and Sign-off Report Desirable skills/knowledge/experience: * Strong analytical and problem-solving skills * Excellent communication and stakeholder management * Ability to work in multi-vendor environments * Proactive risk identification and mitigation