Senior Load Tester

Employer: International cassino games studioLocation: until june 2026 remote, then 5 days from the office in WarsawSalary: up to 5900 EUR net Cooperation model: B2BStart date: ASAPRecruitment process: 2 online interviews and recruitment task Technology stack: k6 or Gatling or JMeter or or Locus, Grafana or Datadog or New Relic, WebSocket Your role is to:-> Design and execute load, stress, spike, and soak tests against critical platform flows; -> Analyze results and pinpoint exactly where and why performance degrades — not just that it does; -> Work closely with backend engineers to understand system architecture and target the right bottlenecks;-> Build and maintain performance test scripts that are reusable, version controlled, and easy to update as the product changes; -> Integrate performance tests into CI/CD pipelines to catch regressions early;-> Define performance benchmarks and thresholds in collaboration with engineering and product teams;-> Monitor platform behavior under load using observability tools and correlate metrics with test results;-> Document findings clearly and present actionable recommendations to engineering teams; Your skills and experiences:-> 5+ years of hands-on performance and load testing experience on production-scale systems;-> Strong practical experience with k6, Gatling, JMeter, or Locust — you've built complex scripts from scratch;-> Good understanding of backend architecture, databases, and how infrastructure behaves under load;-> Comfortable reading and interpreting metrics from tools like Grafana, Datadog, New Relic, or similar;-> Solid understanding of HTTP, WebSockets, and real-time communication protocols;-> Experience testing APIs under load including auth flows, concurrent sessions, and stateful scenarios;-> Familiar with CI/CD pipelines and integrating performance tests into automated build processes;-> Fluent with Git and working within agile engineering teams;-> Curious by nature — you enjoy understanding why a system behaves the way it does under pressure;-> Sharp analytical mind — you can look at a wall of metrics and know exactly where to focus;-> Clear communicator — you can explain a complex performance issue to a developer and a product manager in the same conversation;-> Self-driven — you don't wait to be told there's a problem; you go looking for one;-> Fluent English - at least B2+ level; If interested, please apply safely through this portal (application rules are in accordance with GDPR). Employment agency Nr 17138.