Test Engineer

Role: Test Engineer — Protocol Conformance & Performance (4G/5G Core)Team: Core Network Engineering — Test & QualityLevel: Senior Test EngineerLocation: Espoo, Finland About the Role: Client is building a cloud-native, high-scale 4G/5G converged packet core for NB-IoT, targeting 100M+ connected devices and 70,000+ transactions per second. We're hiring a test engineer to own both halves of quality for this core: provingit's 3GPP-conformant, and proving it holds up under real load, real failures, and real disaster-recovery scenarios — all inside our AWS deployment.You'll work across both the 4G (EPC/MME) and 5G (5GC/AMF/SMF) stacks, using industry-standard tooling alongside our own internal simulators. You're the person who can say, with evidence, "yes, this meets spec — and yes, it survives a bad day." What You'll Own3GPP Protocol ConformanceBuild and maintain automated conformance suites for NAS, S1AP, NGAP, and Diameter (S6a/SGd) against 3GPP Release 16/17+, using commercial test platforms (e.g., Spirent) plus lightweight internal simulators.Gate every pull request on conformance results in CI/CD — a protocol regression fails the PR, not the release.Write new test cases as the protocol surface grows, with traceability from each case back to the governing 3GPP clause.Triage PCAP-level findings and work directly with core developers to root-cause failures. Load, Capacity & Scale TestingDesign and run load campaigns validating the core at 70,000+ TPS.Run long-haul soak tests rotating 50M–200M subscriber identities to catch memory leaks, datastore key growth, and connection drift that short performance tests miss.Own throughput, latency (p95/p99), and capacity reporting each test cycle. High Availability & Disaster RecoveryBuild and run chaos-engineering scenarios (pod eviction, AZ network partition, node termination) using tools such as Chaos Mesh or LitmusChaos — injected during live load, not as a separate exercise.Validate non-sticky routing, automatic failover, and non-disruptive state recovery from the shared datastore layer (Valkey/MemoryDB).Validate rolling-upgrade and rollback procedures as part of the release process. Test Automation & AWS EnvironmentDesign, build, and maintain test automation frameworks from the ground up — covering conformance, load, and resiliency testing end to end, not just executing pre-built suites.Integrate all automated test suites into CI/CD so results gate merges and releases without manual intervention.Run all of the above against our actual AWS deployment topology (EKS, multi-AZ, Terraform/Helm-managed infrastructure) — not a lab approximation. What We're Looking For5+ years in telecom protocol/system test engineering, with hands-on 3GPP conformance testing (NAS, S1AP/NGAP, Diameter).3+ years of hands-on test automation experience — building and maintaining automated test frameworks integrated into CI/CD, not just running manual or pre-built test suites.Practical experience with chaos engineering / resiliency testing (Chaos Mesh, LitmusChaos, or equivalent) in a Kubernetes environment.Comfortable working in AWS (EKS, multi-AZ architecture); scripting ability in Python or Go for test automation.Familiarity with SCTP, Wireshark/PCAP analysis, and Prometheus/Grafana-based observability.Bonus: Experience with the Keysight Landslide test platform is an added advantage. What Success Looks LikeThe conformance suite runs as a CI gate with a defined pass/fail bar — not a manual, occasional exercise.Load/HA/DR test results are trusted inputs to release go/no-go decisions.When something breaks in a demo or in production, a new test case exists for it within the week.