Freelance Backend Software Engineer

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 a large-scale cloud migration project, moving critical backend services and infrastructure from AWS to Azure. This is a hands-on freelance contract opportunity for a senior engineer with deep Java expertise, strong cloud migration experience, and a passion for building scalable, high-performance backend systems. You’ll work closely with cross-functional engineering teams to modernise services, improve architecture, and ensure smooth integration across cloud environments. Key Responsibilities Design, refactor, and migrate scalable backend systems and REST APIs using Java and Spring Boot Support AWS to Azure migration activities across applications and infrastructure Re-architect and modularise services to improve scalability, maintainability, and performance Implement secure identity, secrets management, and key vault solutions Integrate third-party services including sports data, video, and commentary providers Build and maintain APIs supporting web and mobile applications Deliver infrastructure changes using Infrastructure as Code tools such as Terraform and Bicep Manage deployments and automation through CI/CD pipelines Monitor, troubleshoot, and optimise cloud services and application performance Collaborate in sprint planning, technical discussions, and code reviews Produce clear technical documentation for systems, APIs, and migration processes Required Skills & Experience Essential Strong commercial experience with Java and Spring Boot Proven experience delivering AWS → Azure migration projects Strong understanding of cloud security, IAM, secrets management, and key vaults Experience designing and integrating RESTful APIs Docker containerisation experience Kubernetes experience across EKS and/or AKS Strong knowledge of AWS services including S3, DynamoDB, and RDS Experience with Azure services including Cosmos DB, Blob Storage, and Azure Database for MySQL Cloud networking knowledge including VPCs, VNets, API Gateway, and API Management Infrastructure as Code experience with Terraform CI/CD pipeline automation using tools such as GitLab, Bitbucket Pipelines, or ArgoCD Desirable Cloud cost optimisation and performance tuning experience Strong testing and QA practices including automation and regression testing Kafka or other event-driven architecture experience SQL database experience including PostgreSQL, MySQL, or Azure SQL If you're an experienced backend engineer looking for your next freelance contract within a modern sports technology environment, we’d love to hear from you.