Principal Server Engineer

Userwise Services; España; Presencial; EUR 106.000 - 158.000; Jornada completa

Ventajas ofrecidas por este puesto de trabajo

Paid Time Off

Annual Performance Reviews

Descripción de la vacante

Userwise Services in Spain is seeking a Principal Server Engineer to own the backend infrastructure powering our live games with 1M+ DAU. You will design, implement, and optimize Go/Python services, own PostgreSQL schemas, and drive horizontal scaling while reducing contention and outages.

You will profile production workloads, lead root-cause investigations, and shape in-memory layers with Redis/KeyDB/Memcached, plus employ Nakama for real-time multiplayer sockets.

Formación

• Deep Go and Python expertise with performance tuning and GC understanding.
• Strong PostgreSQL fluency: scalable schema design and indexing.
• Proven experience scaling live game backends with 350k+ DAU.
• Hands-on profiling to find memory leaks, CPU spikes, and deadlocks.
• Experience with Redis/KeyDB/Memcached for caching and state.
• Familiarity with Nakama, Go/Lua modules, and real-time multiplayer sockets.
• GCP experience for deploying and scaling serverless/containers.
• Load testing and performance investigations across distributed services.

Responsabilidades

• Design, build, and maintain Go/Python backend services for live game titles.
• Own database schema design and query performance in PostgreSQL.
• Drive horizontal scaling and reduce lock contention.
• Profile for memory leaks and CPU spikes, resolve production issues.
• Lead root-cause analyses from detection to resolution.
• Architect and maintain in-memory caching/state layers.
• Design and run load tests to surface breaking points before release.

Conocimientos

Go

Python

PostgreSQL

Performance tuning

Profiling

Distributed systems

Redis/KeyDB/Memcached

Nakama framework

GCP

Load testing

Herramientas

Prometheus

Datadog

Artillery

protobuf/msgpack

Descripción del empleo

About the Role

We'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+ years

Nice to Have

• 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

Requirements

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

Benefits

• Market competitive, tax-free USD salaries
• Paid Time Off
• Annual Performance Reviews