About the Role We're looking for a Principal Server Engineer to own the backend systems powering our live games - services currently supporting 1 M+ DAU. You'll be responsible for performance, scalability, and reliability at the core of our infrastructure, working closely with the engineering team on everything from schema design to incident response. Experience: 8+ years Nice to Have CI/CD and Dev Ops experience (Git Hub Actions, Git Lab CI) plus monitoring/alerting (Prometheus, Datadog) Strong grasp of networking protocols — Web Sockets, g RPC/HTTP2, UDP/TCP tuning for low-latency real-time systems Requirements Responsibilities Design, build, and maintain Go/Python backend services for live, high-traffic game titles, including server-authoritative logic and runtime modules on Nakama Extend and operate Nakama (Heroic Labs) for core game services: authentication, matchmaking, leaderboards, storage, RPCs, and realtime multiplayer Own database schema design and query performance across Postgre SQL systems, including Nakama's storage layer Drive horizontal scaling strategy (Nakama clustering, stateless services), optimizing CPU/memory footprint and reducing lock contention over vertical scaling Profile and resolve memory leaks, CPU spikes, and deadlocks in production Lead root-cause investigations for performance issues and outages, from detection through resolution Architect and maintain in-memory caching/state layers (Redis/Key DB/Memcached) Design and run load tests against Nakama and supporting services to surface breaking points ahead of release Requirements Crucial Deep Go & Python expertise: language internals,



execution models, and performance tuning (goroutine management, GC tuning, zero-allocation techniques) Strong Postgre SQL fluency: scalable schema design, query plan analysis, index strategy optimization, with real examples of resolving bottlenecks via data layout or query architecture changes (experience with Nakama's storage layer or Cockroach DB a plus) Proven experience scaling systems supporting 350k+ DAU, with a horizontal-scaling-first philosophy (efficient serialization/deserialization via Protobuf/Msg Pack, reduced lock contention) Hands-on profiling experience: identifying and resolving memory leaks, CPU spikes, and deadlocks At least 2 concrete examples of complex production performance issues or outages, including root cause analysis and resolution methodology At least 2 released production projects as a core backend engineer handling live traffic Important Practical experience with Nakama (Heroic Labs): custom Go runtime modules (Lua/Type Script a plus), matchmaker, storage engine, realtime sockets, and running Nakama clusters in production Hands-on experience with Redis, Key DB, or Memcached: caching, rate-limiting, state management, including cache stampede mitigation, serialization overhead, and eviction policy design Solid TDD/BDD judgment and practical load-testing experience (e.G., Artillery), including realtime/socket workloads Practical GCP/Google App Engine experience: deploying, monitoring, and scaling serverless/container services Benefits Market competitive, tax-free USD salaries Paid Time Off Annual Performance Reviews #J-18808-Ljbffr

📌 Principal Server Engineer (España)
🏢 UserWise
📍 España