Freelance Backend Software Engineer

Department: Beyond Sports

Location: Hungary, Budapest

Employment Type: Temporary

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.