Middle/Senior Java Developer
Sigma Software22 hours ago
Malmö, SwedenMid Level / Senior
Responsibilities
- Design, develop, and maintain scalable Java backend services and internal frameworks.
- Build and support customer-facing services focused on reliability, availability, security, and performance.
- Investigate and resolve complex production issues involving concurrency and distributed systems.
- Work with authentication, authorization, caching, data storage, and service integrations.
- Contribute to architecture discussions, technical solution design, code reviews, testing, CI/CD, and release activities.
- Coordinate technical dependencies across engineering teams and communicate technical decisions to stakeholders.
- Own features and technical solutions end to end from concept through production support.
Requirements
- At least 4 years of commercial experience in Java backend development.
- Strong hands-on experience with Java, distributed systems, and high-load production environments.
- Deep understanding of Java internals, including the Java Memory Model, garbage collection, concurrency, and multithreading.
- Experience building and scaling customer-facing backend services and debugging production issues.
- Strong knowledge of distributed systems concepts such as consistency, reliability, partitioning, and failure handling.
- Experience with authentication and authorization mechanisms and 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.
- Upper-Intermediate or higher English proficiency.
- Preferred: knowledge of PKCS, KMIP, X.509, AES, KDF, and CA; experience with security- and privacy-sensitive systems; familiarity with machine learning systems or algorithms; and experience with GitHub, Maven, Docker, Kubernetes, or Spinnaker.
- Strong ownership, accountability, analytical and problem-solving skills, attention to detail, communication, collaboration, and ability to work independently.
Benefits
- Long-term onsite project in Malmö, Sweden.
- Opportunity to work on technically challenging, privacy-sensitive products operating at global scale.
- Small autonomous engineering team with end-to-end ownership and emphasis on technical excellence.
- Long-term project stability and an engineering-driven environment with modern technologies.
Tech Stack
Categories
About Sigma Software
Sigma Software is a London-headquartered, privately held IT consultancy that designs and builds custom software for startups and enterprises. The company provides end-to-end services—engineering, web and mobile development, .NET/Java platforms, AR/VR, and UI/UX—delivered via outsourcing, managed teams, and consulting. Founded in 2002, it supports long-term product development and modernization projects across multiple industries for global clients.