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# BACKEND ENGINEER (MID/SENIOR)

- **Company:** Sparta
- **Location:** Madrid, Spain (Remote available)
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), Amazon Web Services, Big Data, Code Review, DevOps, Programming Tools, Python (Programming Language), PostgreSQL, Redis, TypeScript, Data Logging, Backend, Kotlin, Low Latency, Apache Flink, Apache Kafka
- **Published:** August 12, 2026
- **Apply:** https://es.indeed.com/viewjob?jk=4ee408774fe7a2a5

## About the Role

* 4+ years as a software engineer, with production systems you've built and supported.
 * High ownership tendencies
 * Experience in a product-focused organisation, working cross-functionally.
 * Comfortable across multiple languages. We mainly use Kotlin, Java, Python and TypeScript.
 * Able to reason about trade-offs - throughput, latency, consistency, cost - and explain them.
 * At home in system design and in low-level implementation detail.
 * Experience building and deploying services on AWS or GCP.
 * Hands-on exposure to Kafka, Flink, Redis or clustered Postgres, and an appetite for more.
 * Comfortable with agent-based development tools. We use Claude Code; any equivalent is fine.
 * A clear communicator and a pragmatic problem-solver.

NICE TO HAVE EXPERIENCE:

 * Data-intensive applications at scale.
 * Building and interpreting observability - metrics, logging, tracing.
 * Working within or alongside DevOps, SRE or infrastructure teams.
 * Complex distributed environments - high throughput, low latency, large datasets.
 * Any exposure to commodities, energy or financial markets. Useful, but we'll teach you the domain.

## Description

* Design, build and maintain the backend services behind our real-time and analytical data processing.
 * Own features end to end, from shaping the approach to running them in production.
 * Optimise pipelines and services for low latency, high throughput and scale.
 * Work with engineers, product and stakeholders to stay aligned on direction.
 * Contribute to design reviews with a clear view on the trade-offs.
 * Keep your services healthy - observability, feedback loops, incident response.
 * Raise the bar around you through code review, pairing and knowledge sharing.


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