Senior Back-End Java Engineer - Scalable, Privacy-Focused

Sigma Technology; Lunds kommun; On-site; SEK 900,000 - 1,300,000; Full time

Job summary

Sigma Technology in Lund, Sweden, seeks an experienced Java backend engineer to join a team delivering Find My network services at scale. You will design, produce, and maintain scalable, privacy-focused backends and own end-to-end responsibilities from design to production in a fast-changing roadmap.

The role emphasizes autonomy, problem-solving, and collaboration across multiple teams, with focus on concurrency, reliability under load, and clear technical documentation for both technical and

Qualifications

• 5+ years of production experience with Java, including memory model, GC tuning and advanced concurrency utilities
• Proven experience building scalable customer-facing web services addressing auth, availability, reliability and performance under load
• Strong understanding of distributed systems concepts like consistency, partitioning, and failure modes
• Experience with data storage and caching technologies such as Cassandra, Redis, or Memcached
• Experience writing REST-based services using frameworks like Netty
• Knowledge of CI/CD tools and full automation testing
• Excellent written and verbal communication for design docs and cross-team collaboration

Responsibilities

• Design, develop, and maintain scalable backend services for Find My network
• Manage services end-to-end from design to production deployment
• Collaborate with multiple teams to manage cross-team dependencies
• Adapt plans based on evolving goals, threat models, and partner requirements
• Build internal frameworks for use across teams and communities
• Investigate and debug complex concurrency and production issues under load
• Write clear technical documentation and communicate decisions to stakeholders

Skills

Java

Concurrency

Distributed systems

REST/Netty

Caching technologies

CI/CD

Docker

Kubernetes

Maven

Security & auth

Tools

Netty

Maven

Docker

Spinnaker

Kubernetes

Job description

Sigma Technology in Lund, Sweden, seeks an experienced Java backend engineer to join a team delivering Find My network services at scale. You will design, produce, and maintain scalable, privacy-focused backends and own end-to-end responsibilities from design to production in a fast-changing roadmap.

The role emphasizes autonomy, problem-solving, and collaboration across multiple teams, with focus on concurrency, reliability under load, and clear technical documentation for both technical and