Senior Java Developer (Security Platform)

Are you passionate about building secure, high-performance platforms? We are looking for a Senior Java Developer to join our team and work on a cutting-edge security platform. This is a remote role open to candidates across Europe and Ukraine.
At Sigma Software, we create innovative solutions for complex ecosystems, ensuring security, scalability, and compliance at every step. You will be part of a talented engineering group designing the unified access layer for distributed services.
Why join us? You will work on a mission-critical project with advanced security architecture, collaborate with skilled professionals, and contribute to a platform that supports global-scale operations.

CUSTOMER

Our customer is a large-scale technology-driven organization operating a complex distributed ecosystem. They are building a unified access and security layer to ensure consistent governance, compliance, and high-performance data access across multiple services. The company is committed to cutting-edge security architecture, multi-tenant isolation, and global regulatory compliance.

PROJECT

The project focuses on developing a centralized platform access layer that integrates API gateway capabilities, service orchestration, data composition, and fine-grained Attribute-Based Access Control (ABAC). This system will serve as the foundation for security and governance across the entire ecosystem, supporting complex organizational hierarchies, regional compliance, and strict enforcement guarantees.

• Design and evolve the platform access architecture for a large-scale distributed ecosystem
• Build and maintain a unified API layer over multiple distributed services
• Implement fine-grained ABAC authorization at scale, supporting complex hierarchies and relationships
• Develop fail-closed security architectures with strict enforcement guarantees
• Manage regional compliance, data residency, and routing requirements
• Ensure consistent data visibility rules across all products and services
• Design high-performance authorization evaluation systems and policy engines
• Maintain auditability, traceability, and security transparency mechanisms
• Collaborate with platform and product teams on API and access design
• Contribute to architectural decisions and security standards

• At least 5+ years of experience building distributed systems
• Strong expertise in Java development
• Experience designing API platforms or API gateways
• Solid background in security architecture and system design
• Experience with authorization systems (RBAC/ABAC or similar)
• Familiarity with cloud-native architectures and scalable, high-availability systems
• Understanding of multi-tenant architectures
• Experience operating complex distributed systems in production
• Strong architectural thinking and problem-solving skills
• Upper-Intermediate or higher English proficiency

WILL BE A PLUS

• Experience with Identity and Access Management (IAM) systems
• Experience building API gateways or service mesh architectures
• Work on security-critical or compliance-heavy systems
• Knowledge of policy engines (e.g., OPA)
• Experience with large-scale enterprise platforms
• Familiarity with cloud providers (e.g., GCP)
• Experience with data governance, audit, and compliance systems
• Background in regulated or high-security environments

PERSONAL PROFILE

• Proactive and detail-oriented
• Thrives in collaborative environments
• Enjoys solving complex integration challenges
• Comfortable experimenting with new technologies
• Committed to improving data systems