Principal Java Engineer

Principal Java Engineer (Contract)

About Our Client

Our Client is a leading technology services provider specialising in delivering innovative, scalable software solutions across various industries. Renowned for fostering a collaborative and forward-thinking culture, they are committed to driving technological excellence and supporting employee growth. Recognised with multiple awards, the organisation prides itself on creating a great place to work where talent thrives and impactful projects are at the forefront.

Role Overview

This exciting contract opportunity involves joining a dynamic team as a Principal Java Engineer. The role is pivotal in shaping critical initiatives within the organisation’s technology portfolio, focusing on designing and developing high-performance backend services. Your expertise will guide strategic technical decisions, contribute to product roadmaps, and influence the organisation’s technological direction. This position offers a chance to work on transformative projects, utilising the latest Java and Spring frameworks, whilst collaborating with diverse teams to deliver innovative solutions.

Key Responsibilities

• Lead the development of complex backend systems using Java (17+) and Spring Boot, incorporating reactive patterns where applicable.
• Design and implement RESTful APIs following contract-first principles, with particular attention to latency-sensitive applications.
• Architect scalable, reliable service integrations leveraging cloud platforms (AWS, GCP, or Azure), including implementation of queues, caches, and managed databases.
• Develop and maintain secure authentication protocols, including OAuth 2.0, OIDC, and SAML, ensuring seamless integration with enterprise identity providers.
• Establish and evolve service architecture standards, encompassing domain modelling, event-driven design, API versioning, and backward compatibility.
• Create robust integration contracts with various enterprise systems, ensuring data consistency and error handling.
• Implement and oversee cross-cutting concerns such as observability, auditability, idempotency, and traceability.
• Drive high system reliability through automated testing, CI/CD pipelines, containerisation, and comprehensive monitoring.
• Collaborate with stakeholders to align technical solutions with business objectives, advising on best practices and optimisation strategies.
• Mentor technical team members, fostering a culture of continuous improvement and innovation.

Essential Skills & Experience

• Over 10 years of professional experience in back-end development, with a significant focus on Java enterprise applications.
• Extensive hands-on experience with the Spring ecosystem (Spring Boot, Spring Security, Spring Data).
• Proven track record in designing and delivering RESTful APIs and event-driven architectures using message brokers like Kafka or RabbitMQ.
• Strong knowledge of cloud deployment and management (preferably AWS, GCP, or Azure).
• Practical experience with relational databases such as PostgreSQL or MySQL, and familiarity with NoSQL systems is advantageous.
• Solid understanding of security protocols, particularly OAuth 2.0, OIDC, and SAML.
• Experience implementing CI/CD pipelines, containerisation (Docker, Kubernetes), and automated testing frameworks.
• Excellent problem-solving skills, with the ability to decompose complex solutions and anticipate project risks.

Desirable Skills & Experience

• Familiarity with loyalty, rewards, or financial calculation engines.
• Experience in building API aggregation layers or BFFs for mobile applications.
• Knowledge of Salesforce CRM, Commerce Cloud, or similar enterprise systems.
• Background working in fintech, payments, or transaction-sensitive environments focusing on auditability and data integrity.
• Experience with feature flagging, progressive rollout strategies, or working closely with mobile development teams.

Why Apply?

If you are a seasoned Java professional eager to lead impactful projects in a collaborative, innovative environment, this contract role presents a unique opportunity to influence significant technical and business outcomes. Our Client welcomes candidates with the right expertise and a passion for building high-quality scalable systems.

Candidates who meet the essential criteria are encouraged to submit their CV for consideration. We look forward to discovering how your skills can contribute to cutting-edge solutions and transformative projects.