> Markdown version of [/jobs/ext/3655003-principal-server-engineer](https://www.wearedevelopers.com/jobs/ext/3655003-principal-server-engineer). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md).

---

# Principal Server Engineer

- **Company:** UserWise Services
- **Location:** A Coruña, Spain
- **Contract:** Permanent contract
- **Skills:** Query Performance, Google App Engines, Continuous Integration, Serialization, Database Schema, DevOps, Github, Protocol Buffers, Python (Programming Language), PostgreSQL, Load Testing, Lua (Scripting Language), Memcached, Network Protocols, Performance Tuning, Redis, Prometheus, Memory Leaks, Database Engines, Transmission Control Protocol (TCP), WebSocket, Datadog, Real Time Systems, Caching, Backend, Gitlab-ci, Grpc, Serverless Computing
- **Published:** October 9, 2026
- **Apply:** https://www.buscojobs.com.es/principal-server-engineer-en-la-coruna-ID-374917927

## About the Role

Crucial
Deep Go & Python expertise - language internals, execution models, and performance tuning (goroutine management, GC tuning, zero-allocation techniques)
Strong PostgreSQL fluency - scalable schema design, query plan analysis, index strategy optimization, with real examples of resolving bottlenecks via data layout or query architecture changes
Proven experience scaling systems supporting 350k+ DAU, with a horizontal-scaling-first philosophy (efficient serialization/deserialization via Protobuf/MsgPack, 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
Hands-on experience with Redis, KeyDB, 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)
Practical experience with the Nakama framework - custom Go/Lua modules, matchmakers, storage engine, real-time multiplayer sockets
Practical GCP/Google App Engine experience - deploying, monitoring, and scaling serverless/container services

## Description

About the RoleWe're looking for a Principal Server Engineer to own the backend systems powering our live games - services currently supporting 1M+ 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+ yearsNice to HaveCI/CD and DevOps experience (GitHub Actions, GitLab CI) plus monitoring/alerting (Prometheus, Datadog)Strong grasp of networking protocols - WebSockets, gRPC/ UDP/TCP tuning for low-latency real-time systemsRequirementsResponsibilitiesDesign, build, and maintain Go/Python backend services for live, high-traffic game titlesOwn database schema design and query performance across PostgreSQL systemsDrive horizontal scaling strategy - optimizing CPU/memory footprint and reducing lock contention over vertical scalingProfile and resolve memory leaks, CPU spikes, and deadlocks in productionLead root-cause investigations for performance issues and outages, from detection through resolutionArchitect and maintain in-memory caching/state layers (Redis/KeyDB/Memcached)Design and run load tests to surface breaking points ahead of releaseRequirementsCrucialDeep Go & Python expertise - language internals, execution models, and performance tuning (goroutine management, GC tuning, zero-allocation techniques)Strong PostgreSQL fluency - scalable schema design, query plan analysis, index strategy optimization, with real examples of resolving bottlenecks via data layout or query architecture changesProven experience scaling systems supporting 350k+ DAU, with a horizontal-scaling-first philosophy (efficient serialization/deserialization via Protobuf/MsgPack, reduced lock contention)Hands-on profiling experience - identifying and resolving memory leaks, CPU spikes, and deadlocksAt least 2 concrete examples of complex production performance issues or outages, including root cause analysis and resolution methodologyAt least 2 released production projects as a core backend engineer handling live trafficImportantHands-on experience with Redis, KeyDB, or Memcached - caching, rate-limiting, state management, including cache stampede mitigation, serialization overhead, and eviction policy designSolid TDD/BDD judgment and practical load-testing experience (e.g., Artillery)Practical experience with the Nakama framework - custom Go/Lua modules, matchmakers, storage engine, real-time multiplayer socketsPractical GCP/Google App Engine experience - deploying, monitoring, and scaling serverless/container servicesBenefitsMarket competitive, tax-free USD salariesPaid Time OffAnnual Performance Reviews#J-*****-Ljbffr