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# Principal Server Engineer

- **Company:** UserWise Services
- **Location:** Spain
- **Contract:** Permanent contract
- **Skills:** Query Performance, Google App Engines, 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, Backend, Gitlab-ci, Grpc, Serverless Computing
- **Published:** September 21, 2026
- **Apply:** https://www.indeed.com/viewjob?jk=646be472f5e4e3af

## 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

* CI/CD and DevOps experience (GitHub Actions, GitLab CI) plus monitoring/alerting (Prometheus, Datadog)
 * Strong grasp of networking protocols - WebSockets, gRPC/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
 * Own database schema design and query performance across PostgreSQL systems
 * Drive horizontal scaling strategy - 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/KeyDB/Memcached)
 * Design and run load tests to surface breaking points ahead of release