Senior Java Backend Engineer — Scalable, Privacy‑Focused Systems

Sigma Software; Malmö kommun; On-site; SEK 700,000 - 900,000; Full time

Job summary

Sigma Software in Malmö is seeking a Middle/Senior Java Backend Developer to join a long-term onsite project focused on privacy-sensitive distributed services used at global scale. You will contribute to scalable backend systems, architecture discussions, and end-to-end deployment and production support.

The role emphasizes collaboration in autonomous teams, technical excellence, and a strong ownership mindset across the full software lifecycle.

Qualifications

• 4+ years of commercial Java backend experience.
• Strong hands-on experience with Java and distributed systems.
• Deep understanding of Java internals, including the Java Memory Model, garbage collection, concurrency, and multithreading
• Experience debugging production issues in high-load environments.
• Strong knowledge of distributed systems concepts, including consistency, reliability, partitioning, and failure handling
• Experience building and scaling customer-facing backend services.
• Experience with authentication and authorization mechanisms.
• Hands-on experience with Cassandra, Redis, Memcached, or similar technologies
• Experience developing REST-based services using Netty or similar frameworks
• Experience with CI/CD pipelines and automated testing
• Strong analytical and problem-solving skills
• Upper-Intermediate or higher level of English

Responsibilities

• Design, develop, and maintain scalable Java backend services and internal frameworks
• Participate in architecture discussions and contribute to technical solution design
• Build and support customer-facing services with a focus on reliability, availability, security, and performance
• Investigate and resolve complex production issues related to concurrency and distributed systems
• Work with authentication, authorization, caching, data storage, and service integrations
• Collaborate with multiple engineering teams and coordinate technical dependencies
• Participate in code reviews, automated testing, CI/CD processes, and release activities
• Prepare technical documentation and communicate technical decisions to stakeholders
• Take end-to-end ownership of features and technical solutions from concept to production

Skills

Java backend

Distributed systems

Java memory model

Concurrency & multithreading

Production debugging

Authentication & authorization

REST services

CI/CD

Analytical thinking

English (Upper-Intermediate+)

Tools

Cassandra

Redis

Memcached

Netty

Maven

Docker

Kubernetes

Spinnaker

CI/CD tooling

Job description

Sigma Software in Malmö is seeking a Middle/Senior Java Backend Developer to join a long-term onsite project focused on privacy-sensitive distributed services used at global scale. You will contribute to scalable backend systems, architecture discussions, and end-to-end deployment and production support.

The role emphasizes collaboration in autonomous teams, technical excellence, and a strong ownership mindset across the full software lifecycle.