Senior Software Development Engineer in Test

This position is open to candidates from anywhere in the world. As a Senior Software Development Engineer in Test (SDET), you will design and build the performance testing systems, infrastructure, and engineering tools that enable a high-scale technology platform to validate application performance, reliability, and scalability under realistic production conditions. This is primarily a performance engineering and infrastructure-focused role, not a traditional manual QA or functional UI automation position. The emphasis is on developing the systems needed to simulate real-world traffic, identify performance bottlenecks, and determine whether applications and infrastructure can handle significant workloads before deployment. A key challenge will be building scalable testing capabilities that can reproduce production-like traffic patterns and infrastructure conditions that conventional staging environments cannot easily simulate. You will combine hands-on performance engineering with software development, cloud infrastructure, and DevOps practices to create reliable, repeatable, and automated testing capabilities. This includes writing code, building testing frameworks and environments, integrating performance validation into CI/CD pipelines, and working closely with platform engineers to understand application behavior at scale. This role is ideal for an engineer with a strong background in performance engineering, scalability, or platform infrastructure who enjoys building technical solutions from the ground up and taking ownership of complex performance and reliability challenges. Responsibilities Design, develop, and maintain scalable performance testing platforms, frameworks, and infrastructure capable of simulating real-world production workloads. Build and execute load, stress, scalability, endurance, and synthetic testing solutions to validate application performance and infrastructure reliability. Develop systems capable of generating realistic traffic patterns and workloads, including high-concurrency scenarios and distributed load testing. Analyze production traffic patterns, historical usage data, and infrastructure metrics to design representative performance testing scenarios. Write production-quality code using TypeScript, Python, or comparable programming languages to develop performance testing tools, frameworks, and supporting infrastructure. Build repeatable testing environments that closely replicate production architecture, resource constraints, and traffic behavior. Identify and investigate performance bottlenecks involving latency, throughput, bandwidth, application response times, CPU, memory, databases, and infrastructure capacity. Use monitoring, observability, and application performance data to analyze testing results, diagnose scalability issues, and recommend improvements. Integrate performance testing and automated validation into CI/CD pipelines to identify scalability risks before production…