> Markdown version of [/jobs/ext/1866442-lead-performance-tester-sdet](https://www.wearedevelopers.com/jobs/ext/1866442-lead-performance-tester-sdet). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Lead Performance Tester (SDET) - **Company:** Vonage - **Location:** Madrid, Spain - **Contract:** Permanent contract - **Skills:** Java (Programming Language), Application Programming Interfaces (APIs), Agile Methodology, Amazon Web Services, Amazon Elastic Compute Cloud, Application Performance Management, Cloud Computing, Code Review, Databases, Continuous Integration, Distributed Systems, Fault Tolerance, Github, Monitoring of Systems, Apache JMeter, Python (Programming Language), Load Testing, Log Analysis, Message Broker, MySQL, Performance Tuning, RabbitMQ, Reliability Engineering, Cloud Services, Software Requirements Analysis, Systems Architecture, Test Data, TypeScript, WebRTC, Scripting, Performance Testing, Grafana, Concurrency, Gatling, Backend, Event Driven Architecture, Integration Tests, Low Latency, Apache Kafka, Cloudwatch, Api Gateway, Restful APIs, SDET, Jenkins, Microservices - **Published:** August 2, 2026 - **Apply:** https://www.jobleads.com/es/job/ebd58a8e40ed10303bd27a8ea08eac231 ## About the Role * Proven experience mentoring and coordinating testing efforts across large, distributed engineering teams (e.g., conducting code reviews, guiding SDETs through framework adoption, and managing cross-team test schedules). * Strong hands-on experience with AWS cloud services (EC2, ECS, RDS, API Gateway) with a focus on scalability and performance optimisation. * Proven expertise in performance testing tools (specifically k6, along with JMeter or Gatling), including test design, execution, and analysis at scale. * Hands-on experience with production traffic shadowing or replay tools (such as GoReplay). * Deep experience testing distributed systems, message brokers (Kafka, RabbitMQ), microservices architectures, and high-volume, low-latency APIs. * Solid backend programming and scripting skills in Python, Java, or TypeScript to build custom performance frameworks and tooling. * Strong understanding of system design , concurrency, throughput, latency, and fault tolerance principles. * Experience implementing performance testing within CI/CD pipelines (Jenkins, GitHub Actions) and enabling continuous performance feedback loops. * Hands-on experience with observability and monitoring tools (Grafana, Coralogix, PMM) for performance analysis and diagnostics. * Experience working within Agile environments and translating performance insights into actionable engineering outcomes., * Demonstrable hands-on experience in backend performance engineering and automation using Python, Java, or TypeScript. * Proven track record of performance, scalability, and resilience testing in AWS-based cloud-native systems. * Strong experience designing large-scale performance test strategies and leading QA/SDET teams to execute them. * Deep understanding of API performance testing, integration testing, and system-level non-functional validation. * Solid grasp of system architecture, distributed systems behaviour, and non-functional testing methodologies. * Experience with observability, monitoring, and log analysis tools. * Familiarity with RESTful APIs and event-driven systems., * Updated CV clearly demonstrating performance engineering leadership, cross-team coordination, AWS expertise, and backend automation frameworks. * Summary of performance testing frameworks, tools (e.g., k6, GoReplay), and CI/CD methodologies implemented. * Detailed examples of performance testing engagements (scale, environments, bottlenecks identified, business impact, improvements delivered). * Evidence of driving performance strategy, mentoring QA/SDET teams, and influencing architecture. ## Description * Define and lead the performance engineering strategy across high-availability, cloud-native telecom platforms. * Lead, train, and coordinate a distributed guild of SDETs across multiple feature teams, guiding them to build, maintain, and execute performance scripts (k6) within their fractional sprint capacity. * Design, develop, and evolve scalable backend performance frameworks using k6, Python, Java, or TypeScript, focusing entirely on APIs, databases, and infrastructure. * Implement and manage production traffic replay strategies (e.g., GoReplay) and complex multi-tenant test data generation to accurately recreate realistic production contention and load profiles. * Own and drive performance, load, stress, endurance, scalability, and resilience testing, including chaos engineering practices (e.g., using AWS Fault Injection Simulator). * Validate real-time communication systems, event-driven architectures (Kafka, RabbitMQ), and high-throughput distributed systems under production-like conditions. * Integrate performance testing into CI/CD pipelines , enabling continuous performance validation, shift-left practices, and automated PR blocking for latency degradation. * Leverage observability tooling (Grafana, CloudWatch, Coralogix, VictoriaMetrics, PMM) to monitor, analyse, and troubleshoot system performance. * Establish performance benchmarks , SLAs, SLOs, and error budgets aligned with business and system requirements. * Collaborate with architecture and data teams to identify bottlenecks, validate database architectures (e.g., MySQL, Tungsten), and present evidence-based investment proposals. * Analyse and optimise performance across both legacy monolith systems (requiring integrated load testing) and modern microservices architectures. ## Related Videos - [Frontend Performance Testing in practice](https://www.wearedevelopers.com/videos/8-frontend-performance-testing-in-practice) - [Innovating Developer Tools with AI: Insights from GitHub Next](https://www.wearedevelopers.com/videos/1268-innovating-developer-tools-with-ai-insights-from-github-next) - [MySQL Protocol Features You Should Be Aware Of](https://www.wearedevelopers.com/videos/100267-mysql-protocol-features-you-should-be-aware-of) - [Continuous testing - run automated tests for every change!](https://www.wearedevelopers.com/videos/190-continuous-testing-run-automated-tests-for-every-change) - [Bringing AI Model Testing and Prompt Management to Your Codebase with GitHub Models](https://www.wearedevelopers.com/videos/1536-bringing-ai-model-testing-and-prompt-management-to-your-codebase-with-github-models) - [Coding for Good: Achieving social change with an app](https://www.wearedevelopers.com/videos/1645-coding-for-good-achieving-social-change-with-an-app) ## Related Articles - [Benefits of Using JMeter For Performance Testing](https://www.wearedevelopers.com/magazine/96-benefits-of-using-jmeter-for-performance-testing) - [The 8 Best Code Testing Tools](https://www.wearedevelopers.com/magazine/402-the-8-best-code-testing-tools) - [Dev Digest 120 - Apple and peers](https://www.wearedevelopers.com/magazine/455-dev-digest-120-apple-and-peers) - [Dev Digest 121 - AI goes offline](https://www.wearedevelopers.com/magazine/456-dev-digest-121-ai-goes-offline) - [Résumé-Driven Development: How IT trends affect the job market for software developers](https://www.wearedevelopers.com/magazine/59-resume-driven-development-how-it-trends-affect-the-job-market-for-software-developers) - [Why Upskilling And Reskilling is Important For Developers](https://www.wearedevelopers.com/magazine/428-why-upskilling-and-reskilling-is-important-for-developers)