Job Description

About TMUS Global Solutions
T-Mobile is America's supercharged Un-carrier, challenging conventions and setting new standards in wireless. With the nation's largest and fastest 5G network, T-Mobile delivers advanced connectivity and unmatched value to millions across the U.S. We're unwaveringly obsessed with providing the best possible service experience, driven by a spirit of disruption that fuels competition and innovation in wireless and beyond.
Disclaimer: TMUS India Private Limited is a subsidiary of T-Mobile US, Inc. and operates as TMUS Global Solutions. TMUS India Private Ltd., and T-Mobile US, Inc., do not provide telecommunication services in India.

About the Role
The Senior Site Reliability Engineer (Performance) is a hands-on engineering role focused on ensuring that customer-facing and internal applications deliver optimal performance, scalability, and resiliency. This role goes beyond traditional testingprofiling Java/Spring Boot applications, tuning Kubernetes workloads, analyzing network issues, and applying cloud-native best practices to drive systemic improvements. The engineer designs and automates performance tests, formulates hypotheses, and uses data-driven insights to recommend or implement fixes at code, infrastructure, and architecture levels. With an automation-first mindset, they embed performance engineering into CI/CD pipelines and partner with developers, architects, and SREs to create a performance-first culture.
What Youll Do

• Profile and optimize Java/Spring Boot microservices, diagnosing memory leaks, GC issues, thread contention, and improving latency and throughput
• Design and execute performance tests (load, stress, spike, endurance) using tools such as JMeter, k6, Gatling, Locust, or LoadRunner
• Develop reusable test frameworks and integrate performance tests into CI/CD pipelines
• Build load/capacity models and design experiments to test scalability under real-world conditions
• Analyze and optimize Kubernetes workloads (EKS/AKS/GKE), tuning autoscaling, pod configs, and Helm charts
• Use observability tools (AppDynamics, Prometheus, Grafana, Splunk) and tracing to identify performance bottlenecks
• Conduct performance diagnostics across network layers (TCP/IP, gRPC, HTTP/REST)
• Mentor engineers and participate in design reviews to embed performance practices from the start

What Youll Bring

• 47 years of experience in performance engineering or backend system optimization
• Strong Java/Spring Boot development background
• Hands-on experience with Kubernetes-based environments and container optimization
• Familiarity with AWS (preferred), Azure or GCP acceptable
• Experience with performance/load testing tools: JMeter, k6, Gatling, Locust, or LoadRunner
• Ability to conduct network analysis and work with observability tools
• Experience in embedding performance tests into CI/CD pipelines
• Strong collaboration and mentoring skills

Must Have Skills

• Java / Spring Boot
• Kubernetes (EKS/AKS/GKE)
• Performance testing tools: JMeter, k6, Gatling, LoadRunner
• Observability: Prometheus, Grafana, AppDynamics, Splunk
• CI/CD integration (e.g., GitLab, Jenkins)
• JVM profiling tools: JFR, JProfiler, VisualVM

Nice To Have

• Cloud: AWS (preferred), Azure, GCP
• Distributed tracing (Open Telemetry, Jaeger)
• Helm, Terraform
• Network-level analysis (HTTP/2, gRPC, TLS optimization)
• Experience mentoring SRE or developer teams on performance best practices
• Performance-related certifications (Java, Kubernetes, AWS

Skills Required