Senior Java Backend Engineer

We are seeking an experienced Senior Java Backend Engineer to join our dynamic team in Malmö, Sweden. This role demands deep expertise in Java and a strong background in building and scaling customer-facing web services. The ideal candidate will have significant production experience, a robust understanding of distributed systems, and familiarity with various data storage and caching technologies. You will be responsible for developing reliable, high-performance services, troubleshooting complex production issues, and contributing to architecture and design decisions in a collaborative environment.

• Develop and maintain scalable, reliable, and high-performance Java backend services
• Collaborate with cross-functional teams to design and implement new features
• Investigate and resolve complex production issues under real-world concurrency and load
• Optimize application performance including tuning garbage collection and allocation pressure
• Read and analyze source code of dependencies to solve problems beyond available documentation
• Implement and enhance authentication, authorization, and spam control mechanisms
• Contribute to the design of distributed systems ensuring robustness and fault tolerance
• Write clear design documents and communicate technical decisions effectively to both technical and non-technical stakeholders
• Participate in CI/CD practices and ensure high-quality automated tests are in place
• Operate primarily on-site in Malmö, maintaining effective communication in English

Basic qualifications

• 5+ years of production experience in backend Java development
• Deep understanding of Java memory model, garbage collection, and concurrency utilities
• Experience debugging production issues under real load and concurrency
• Proven expertise in building and scaling customer-facing web services including authentication and authorization
• Strong knowledge of distributed systems concepts such as consistency, partitioning, and failure modes
• Hands-on experience with data storage and caching systems like Cassandra, Redis, or memcached
• Experience writing RESTful services using Netty or similar frameworks
• Proficiency with CI/CD tooling and full automation testing
• Excellent written and verbal communication skills in English

Preferred additional skills, personal traits and experience

• Knowledge of cryptography standards and protocols (PKCS, KMIP, X.509, AES, KDF, CA)
• Familiarity with machine learning systems, frameworks, and algorithms
• Experience with GitHub and build and deployment tools such as Maven, Docker, Spinnaker, and Kubernetes