Thyreos Cyber, part of EFA Group, delivers defence‑grade cybersecurity services and platforms for mission‑critical and high‑assurance environments. The company combines deep expertise across Aerospace, Defense, High‑Technology and Security with advanced cyber engineering capabilities to support organisations operating where resilience, readiness, and operational impact matter most. At the core of its offering is a Cyber Range platform with Digital Twins, enabling organisations to safely train, rehearse missions, validate tools and procedures, and assess the operational impact of decisions in realistic, controlled environments, alongside a comprehensive portfolio of offensive and defensive cyber services.
We are looking for a Backend Engineer to help build the core services of its cyber exercise platform. The role focuses on backend architecture, APIs, orchestration logic, and platform reliability, supporting the design, execution, and lifecycle of cyber exercises across red team, blue team, and tabletop workflows. The Backend Engineer works closely with frontend, infrastructure, and scenario teams to ensure the platform operates reliably, scales effectively, and delivers realistic, mission‑focused cyber exercise capabilities.

Key Responsibilities

• Design, build, and maintain backend services and APIs for the platform
• Implement core platform logic for exercise lifecycle management, scenario execution, scoring, reporting, and user and team management
• Contribute to orchestration workflows for provisioning and managing exercise environments
• Build integrations with infrastructure and platform components to support repeatable deployments
• Ensure secure authentication, authorization, logging, and auditing practices
• Collaborate with frontend and scenario teams to translate product requirements into backend capabilities
• Contribute to system design, documentation, and technical standards
• Support reliability, performance, and maintainability of backend services

Required Qualifications & Skills

• Professional experience in backend software engineering with Go or another modern backend language
• Experience designing and building APIs and backend services in production environments
• Understanding of distributed systems, asynchronous workflows, and service integration
• Familiarity with databases, messaging or event-driven patterns, and system observability
• Ability to work on more than simple CRUD applications and contribute to architecture decisions
• Understanding of secure software development practices
• Comfortable working across product, infrastructure, and technical delivery requirements

Nice to have

• Experience with Go and backend or control‑plane systems involving orchestration and automation
• Familiarity with virtualization, cloud or private infrastructure environments, and containerized platforms using Docker, Kubernetes, Terraform, or Ansible
• Exposure to cybersecurity platforms, training systems, lab or simulation environments
• Ability to work independently, take ownership of technical deliverables, and maintain strong written communication and documentation discipline
• Eligibility for security clearance, if required

We offer

• Competitive remuneration package
• Private medical insurance package
• Continuous learning & development opportunities
• Participation in cultural and team-building activities
• Exposure to a growing environment with cutting-edge technologies
• Corporate wellness initiatives