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# Senior Software Engineer

- **Company:** New Relic
- **Location:** Barcelona, Spain
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), Profiling, Continuous Integration, Serialization, Data Stores, Software Design Documents, Distributed Systems, Memory Management, Elasticsearch, Fault Tolerance, Protocol Buffers, Java Virtual Machine (JVM), Redis, Rxjava, Backend, Kotlin, Event Driven Architecture, Kubernetes, Apache Flink, Cassandra, Avro, Apache Kafka, Reactive Programming, Video Streaming, Asynchronous Programming, Api Design, Stream Processing, Microservices
- **Published:** September 23, 2026
- **Apply:** https://www.indeed.com/viewjob?jk=582341d9f321c125

## About the Role

* Design, build, and operate JVM-based microservices (primarily Java and Kotlin) with a focus on performance, scalability, and reliability.
 * Own services end-to-end: architecture, implementation, deployment, monitoring, on-call participation, and continuous improvement.
 * Apply strong concurrency and performance practices: asynchronous programming, backpressure, efficient I/O, memory management, and GC tuning.
 * Build and evolve event-driven systems; work with Kafka for streaming, partitioning, consumer groups, and schema evolution.Instrument services for deep observability (metrics, logs, traces), define SLIs/SLOs, and use e
 * Experience with Kafka or similar streaming technologies (topic/partition strategy, consumer lag, idempotency, schema compatibility) strongly preferred.
 * Proficiency with REST/gRPC API design, service-to-service communication, and resilience patterns (timeouts, retries, circuit breakers).
 * Practical experience with containers and Kubernetes, and with CI/CD pipelines.
 * Track record of operating services in production: monitoring, alerting, incident response, and postmortems.
 * Strong communication skills, ability to write design docs, and collaborate across teams; proficiency in rror budgets to drive reliability.
 * Automate CI/CD, testing, and operational tasks; improve developer productivity with tooling and infrastructure as code.
 * Collaborate with product, architecture, and cross-functional partners to deliver customer outcomes.
 * Mentor peers, review designs and code, and contribute to technical standards and best practices.

This role requires

 * Strong experience building and operating production-grade backend services on the JVM (Java and/or Kotlin).
 * Solid understanding of distributed systems concepts (consistency, partitioning, replication, fault tolerance) and microservice design.
 * Hands-on experience with asynchronous and reactive programming (e.g., CompletableFuture, Project Reactor, RxJava, Kotlin coroutines)

Bonus points if you have

 * Deep JVM performance profiling and tuning experience (JFR, async-profiler, JMH).
 * Experience with schema registries and serialization formats (Avro, Protobuf), and stream processing (Kafka Streams, Flink).
 * Familiarity with data stores used in observability stacks (e.g., Cassandra, Elasticsearch, Redis) and their trade-offs at scale.
 * Experience with OpenTelemetry
 * Prior technical mentorship or leadership in reliability and performance initiatives.