Full Stack Java Lead Developer

This role sits within a large, complex technology organisation operating in the financial services sector. You will play a key part in designing and delivering highly scalable, resilient systems that support critical business functions.

We are seeking a highly experienced Java Full-Stack Lead Developer with strong system architecture expertise. This is a hands-on leadership position where you will own technical direction, drive architectural decisions, and lead a globally distributed engineering team - while remaining actively involved in development.

Please note: This role requires on-site attendance in Sheffield three days per week. This is a firm requirement and not open to remote or reduced-attendance arrangements. What You'll Do

• Lead the architecture and design of complex, high-availability distributed systems
• Make critical decisions on system design, technology selection, and architectural trade-offs
• Drive end-to-end development across Back End and Front End, with hands-on coding
• Lead and coordinate engineers across multiple locations and time zones
• Define and enforce engineering best practices, coding standards, and design principles
• Conduct architecture reviews, design reviews, and code reviews
• Optimise system performance, scalability, resilience, and reliability
• Troubleshoot and resolve complex production and distributed system issues
• Collaborate closely with product, design, and business stakeholders

Essential Skills & Experience Architecture & System Design (Must Have)

• Proven Experience designing large-scale distributed systems
• Strong expertise in:

• Microservices and event-driven architectures
• High-concurrency and scalability patterns
• API design and service boundaries
• Fault tolerance and resilience

• Deep understanding of architectural trade-offs (eg consistency vs availability, latency vs throughput)
• Experience with system decomposition and domain modelling

Backend

• Expert-level Java Experience (Java 8/11/17+)
• Strong hands-on Experience with Spring Boot and Spring Cloud
• Deep understanding of RESTful APIs and microservices
• Experience with ORM frameworks such as Hibernate and JPA

Frontend

• Strong hands-on Experience with at least one modern framework (React, Angular, or Vue)
• Solid understanding of Front End architecture and state management
• Ability to contribute to Front End architectural decisions, not just implementation

Data & Infrastructure

• Strong Experience with relational databases (Oracle, SQL Server, PostgreSQL)
• Experience with distributed caching (eg Redis)
• Experience with messaging platforms (Kafka, RabbitMQ)
• Familiarity with Docker, Kubernetes, and CI/CD pipelines

Desirable Experience

• Proven track record of leading large-scale technical initiatives
• Strong stakeholder engagement and cross-team collaboration skills

Nice to Have (Strong Differentiators)

• Cloud-native architecture Experience (AWS, Azure, or GCP)
• Experience designing multi-region or global systems
• Exposure to AI-enabled systems (eg LLMs, RAG, vector databases)
• Experience with observability tooling (metrics, logging, distributed tracing)

Trading as TEKsystems. Allegis Group Limited, Bracknell, RG12 1RT, United Kingdom. No. 2876353. Allegis Group Limited operates as an Employment Business and Employment Agency as set out in the Conduct of Employment Agencies and Employment Businesses Regulations 2003. TEKsystems is a company within the Allegis Group network of companies (collectively referred to as "Allegis Group"). Aerotek, Aston Carter, EASi, Talentis Solutions, TEKsystems, Stamford Consultants and The Stamford Group are Allegis Group brands. If you apply, your personal data will be processed as described in the Allegis Group Online Privacy Notice available at our website.