Senior Software Engineer

(Distributed Systems | WebSockets | Cloud-Native Scale)

We are seeking a Senior Load & Performance Engineer to own performance engineering for high-scale, real-time, event-driven systems operating at production traffic levels.

This role is deeply hands-on and architecture-adjacent. You will design and execute distributed load tests at massive concurrency (100K+ WebSocket connections), build scalable performance frameworks, and ensure our systems hold up during peak, revenue-critical sporting events.

You’ll operate in a cloud-native, Kubernetes-based environment, using K6, Testkube, GitHub Actions, and AWS-native security patterns to run production-grade performance tests safely, securely, and repeatably.

This is not a script-runner role. This is performance engineering at scale.

• Own end-to-end performance testing strategy for real-time and transactional systems
• Design and execute load, stress, spike, endurance, and soak tests in production and pre-prod environments
• Define performance baselines, SLOs, and regression thresholds
• Drive shift-left performance validation during design and development

• Design distributed WebSocket load tests supporting 100,000+ concurrent connections
• Architect parallel test execution across multiple Kubernetes pods using CI/CD orchestration
• Model realistic traffic patterns for:
  • Sportsbook odds updates
  • Bet Builder workflows
  • Real-time market data streams
• Prevent resource exhaustion issues (OOM, CPU saturation) through smart test distribution and profiling

• Build and evolve K6-based performance frameworks
• Integrate tests into GitHub Actions pipelines with configurable parallelism
• Use Testkube for Kubernetes-native test execution
• Implement dynamic test profile generation (no-code-change test tuning)
• Enable fast iteration during live events without redeploying code

• Implement production-grade security for performance tests using:
  • AWS SSM Parameter Store
  • CSI Secrets Store Driver
  • IAM Roles for Service Accounts (IRSA)
• Ensure zero hardcoded secrets, strict environment isolation, and full auditability
• Leverage Datadog, metrics, logs, and traces to:
  • Identify bottlenecks
  • Validate SLOs in real time
  • Produce actionable post-test analysis

• Partner closely with backend engineers, SREs, and platform teams
• Translate performance findings into concrete engineering actions
• Influence architectural decisions with data, not opinions
• Act as a performance authority during game days and production readiness reviews

• 7+ years of experience in performance, load, or scalability engineering
• Proven experience testing distributed, cloud-native systems
• Strong hands-on experience with K6 (or Gatling/Locust with willingness to go deep in K6)
• Experience with WebSocket performance testing at scale
• Solid programming skills (JavaScript, Java, Python, or similar)
• Deep understanding of:
  • Concurrency, async processing, and event-driven systems
  • HTTP, WebSockets, messaging/streaming patterns
• Experience running tests in Kubernetes environments<