Freelance Backend Software Engineer

Job description

## Senior Backend Java Engineer (Freelance Contract) – Hungary **Contract Length:** 3+ Months **Start Date:** ASAP **Day Rate:** 120,000 HUF – 180,000 HUF per day **Location:** Hungary **About the Role** Beyond Sports is looking for an experienced **Senior Backend Java Engineer** to support the development, scaling, and modernisation of our high-performance backend systems and cloud infrastructure. This is a hands-on freelance contract opportunity for a senior engineer with deep Java expertise, strong cloud experience, and a passion for building resilient, scalable systems. You’ll work closely with cross-functional engineering teams to refactor core microservices, improve system architecture, and ensure low-latency integrations across our web and mobile platforms. **Key Responsibilities** - Design, refactor, and maintain scalable backend microservices and REST APIs using Java and Spring Boot - Re-architect existing backend systems to optimize for maintainability, reliability, and throughput - Implement secure identity, secrets management, and authentication standards across cloud environments - Integrate third-party systems, including real-time sports data feeds, video streams, and commentary providers - Deploy and manage containerised services using Docker and Kubernetes - Provision and maintain cloud infrastructure using Infrastructure as Code (IaC) tools like Terraform - Build, automate, and manage deployment workflows using modern CI/CD pipelines - Monitor, troubleshoot, and optimize application and database performance - Participate in technical planning, architectural discussions, and peer code reviews - Produce clear, maintainable technical documentation for APIs and core backend systems **Required Skills & Experience** *Essential* - Strong commercial contracting experience with **Java** and **Spring Boot** - Proven background building, deploying, and maintaining applications in production cloud environments (**AWS** or **Azure**) - Hands-on experience with containerisation and orchestration using **Docker** and **Kubernetes** - Expertise in designing and building secure, high-traffic **RESTful APIs** - Practical experience writing Infrastructure as Code using **Terraform** - Solid working knowledge of relational and NoSQL databases (e.g., **PostgreSQL**, **MySQL**, **DynamoDB**, **Cosmos DB**) - Deep understanding of cloud security fundamentals (IAM, secrets management, key vaults) - Experience setting up and maintaining CI/CD pipelines (e.g., **GitLab CI**, **Bitbucket Pipelines**, or **ArgoCD**) *Desirable* - Experience with event-driven architectures using **Apache Kafka** or similar messaging systems - Prior exposure to performance tuning and cloud cost-optimisation strategies - Strong automated testing practices (unit, integration, and regression testing) - Understanding of cloud networking components (VPCs/VNets, API Gateways)