Senior Java Software Engineer

Freelance/B2B

Remote/Lisbon

Our client, a global consultancy, are in the midst of delivering a multi-year programme of work in to one of the leading providers of online payment platforms.

You will work as part of a multidisciplinary engineering team delivering cloud-native applications, microservices, and data-driven platforms. The role offers the opportunity to work with modern Java frameworks, scalable architectures, and cloud technologies in environments where reliability, performance, and engineering quality are critical.

The role

You will contribute to the design and delivery of backend systems supporting complex enterprise platforms and high-volume workloads.

Key responsibilities include

Backend Development (Java / Spring Boot)

• Design and develop high-quality backend services using Java and Spring Boot
• Build and maintain RESTful APIs and microservices architectures
• Implement robust data models and integrate with relational and NoSQL databases

Distributed Systems & Cloud Architecture

• Develop scalable, cloud-native applications deployed on modern cloud platforms
• Contribute to the design of event-driven and asynchronous architectures
• Ensure systems are resilient, secure, and capable of handling large-scale workloads

Integration & Platform Development

• Integrate backend services with third-party APIs, internal platforms, and data pipelines
• Support the development of enterprise-grade platforms and digital products

CI/CD & DevOps Collaboration

• Work with DevOps teams to implement and maintain CI/CD pipelines
• Support containerised deployments using Docker and Kubernetes
• Contribute to infrastructure automation and modern delivery practices

Engineering Quality & Best Practices

• Promote clean code, testing, and maintainable architecture
• Contribute to code reviews, technical design discussions, and architectural decisions
• Support strong testing practices including unit, integration, and automated testing

Requirements

• Strong commercial experience with Java (Java 11 preferred)
• Experience developing applications with Spring Boot and the Spring ecosystem
• Experience designing microservices or distributed systems
• Familiarity with cloud platforms (AWS, GCP, or Azure)
• Experience building and maintaining REST APIs
• Understanding of containerisation and modern CI/CD practices

Desirable Experience

• Experience with event-driven architectures (Kafka, Pub/Sub, RabbitMQ, etc.)
• Experience working in consultancy or client-facing delivery environments
• Knowledge of Kubernetes or cloud-native deployment patterns
• Exposure to data-intensive or high-scale platforms