We are looking for a highly skilled **Senior Performance Testing Engineer** to spearhead the design, execution, and analysis of performance testing strategies for scalable, high\-performance systems. In this role, you will develop and optimize performance testing frameworks, identify and resolve bottlenecks in web applications and APIs, and collaborate with cross\-functional teams to ensure our technology meets the highest standards of reliability and scalability. EPAM is a leading global provider of digital platform engineering and development services. We are committed to having a positive impact on our customers, our employees, and our communities. We embrace a dynamic and inclusive culture. Here you will collaborate with multi\-national teams, contribute to a myriad of innovative projects that deliver the most creative and cutting\-edge solutions, and have an opportunity to continuously learn and grow. No matter where you are located, you will join a dedicated, creative, and diverse community that will help you discover your fullest potential. **Responsibilities** * Provide technical expertise in defining and implementing performance testing strategies, frameworks, and plans * Conduct comprehensive performance, load, stress, and endurance testing for web applications and backend APIs * Develop realistic workload models based on architecture and production usage patterns * Analyze and interpret performance test results using tools like k6 and sitespeed.io, identifying key performance metrics * Investigate and resolve performance bottlenecks across application, infrastructure, database, and network layers * Integrate performance test suites into CI/CD pipelines to ensure ongoing scalability and reliability * Utilize Grafana with InfluxDB to capture and visualize performance metrics for trend analysis and reporting * Monitor system resource utilization (CPU, memory, disk, network) during tests and identify misconfigurations * Automate performance testing processes, including test execution and reporting workflows, using scripting or programming tools like TypeScript or PowerShell * Collaborate with stakeholders to identify performance risks early and propose actionable solutions * Lead or contribute to performance tuning initiatives, ensuring the system meets required SLAs and scalability requirements * Mentor and guide team members to foster a performance\-first mindset and skills development **Requirements** * Proven experience of over 3 years in performance testing of web applications, APIs, and backend services * Strong knowledge of performance testing methodologies and best practices * Hands\-on expertise with k6; familiarity with sitespeed.io is a plus * Proficiency in analyzing test outcomes with metrics like percentiles, distributions, and system resource utilization * Experience using Grafana and InfluxDB for performance monitoring, visualization, and reporting * Knowledge of SQL with capabilities in query performance analysis and optimization * Competency in diagnosing and addressing bottlenecks across application, network, OS, and database layers * Understanding of infrastructure configurations, load balancing, and system monitoring tools * Skills in scripting or programming (e.g., TypeScript, PowerShell) for extending performance tests and custom automation * Experience integrating tests into CI/CD workflows with automated reporting tools * Strong communication skills in business English (B2 level or higher) to present findings to both technical and non\-technical audiences **Nice to have** * Familiarity with Prometheus for advanced monitoring and alerting * Experience with testing and optimization in REST and SOAP\-based services * Working knowledge of sitespeed.io for performance analysis and insights * Experience mentoring team members and promoting a performance\-focused culture **We offer** * Connectivity Bonus (25,000 ARS are paid with a salary receipt at the end of each month as a non\-wages concept). * Medicina Prepaga (It covers the collaborator and direct family group). * Paternity Leave (Two additional days are added to what is established by law, total of 4 days). * Discounts card. * English Training (English lessons, twice per week). * Training Program (Access to multiple customized training plans according to the needs of each role within the company). * Marriage bonus (The company doubles the allowance established by law that ANSES offers). * Referral Program (Referral bonus is paid when the referral of a collaborator joins the Company). * External Agreements and Discounts. * Vacations: 14 calendar days a year *By applying to our role, you are agreeing that your personal data may be used as in set out in EPAM´s Privacy Notice and Policy.*