28 senior java developer jobs found in London

About Synechron: Synechron is a leading digital transformation consulting firm dedicated to delivering innovative technology solutions within banking, financial services, and insurance. We thrive on engineering excellence, collaboration, and a passion for cutting-edge technologies. Job Location: London (Hybrid - 3 days in the office) About the role: We are seeking a highly experienced Senior Java Developer with over 10 years of hands-on Java development experience and extensive exposure to AI/ML-driven systems . The ideal candidate will design, build, and scale enterprise-grade applications while integrating modern AI capabilities such as machine learning models, generative AI, and intelligent automation into Back End systems. Key Responsibilities Design, develop, and maintain high-performance, scalable Java applications using modern frameworks. Architect and implement AI-enabled solutions , integrating ML/AI models into Java-based platforms....

We have an exciting opportunity for experienced Java developers to join our team! You will have a passion for software development and an excellent understanding of how to define and deliver solutions iteratively and collaboratively. You will be involved in all areas of delivery, with the technical gravitas to mentor and inspire the development team; playing an integral part in helping them continuously improve by sharing your own knowledge, experience and insights. You will be confident in challenging business requirements to ensure you are continuously delivering the best possible outcome, harnessing innovation and driving the adoption of new technologies to deliver business value. Your vision and ambition will contribute to shaping our online technology roadmap, influencing our future technical direction and balancing passion with precision to deliver exceptional online service and solutions for our customers.   This is an initial six month contract that sits...

We have an exciting opportunity for experienced Java developers to join our team! You will have a passion for software development and an excellent understanding of how to define and deliver solutions iteratively and collaboratively. You will be involved in all areas of delivery, with the technical gravitas to mentor and inspire the development team; playing an integral part in helping them continuously improve by sharing your own knowledge, experience and insights. You will be confident in challenging business requirements to ensure you are continuously delivering the best possible outcome, harnessing innovation and driving the adoption of new technologies to deliver business value. Your vision and ambition will contribute to shaping our online technology roadmap, influencing our future technical direction and balancing passion with precision to deliver exceptional online service and solutions for our customers.   This is an initial six month contract that sits...

We have an exciting opportunity for experienced Java developers to join our team! You will have a passion for software development and an excellent understanding of how to define and deliver solutions iteratively and collaboratively. You will be involved in all areas of delivery, with the technical gravitas to mentor and inspire the development team; playing an integral part in helping them continuously improve by sharing your own knowledge, experience and insights. You will be confident in challenging business requirements to ensure you are continuously delivering the best possible outcome, harnessing innovation and driving the adoption of new technologies to deliver business value. Your vision and ambition will contribute to shaping our online technology roadmap, influencing our future technical direction and balancing passion with precision to deliver exceptional online service and solutions for our customers.   This is an initial six month contract that sits...

We are looking for Senior Java Developers to join on a contract basis (Inside IR35) . The ideal candidate will have experience building scalable microservices, working with event-driven systems, and deploying applications using containerized and cloud technologies. You will contribute to developing reliable backend services and help modernize legacy systems into cloud-ready architectures. Key Skills & Responsibilities Strong experience with Java (latest versions) and Spring Boot Experience designing and developing Microservices architectures Solid understanding of backend design patterns and best practices Experience working with SQL databases, particularly PostgreSQL Knowledge of Object-Oriented programming principles (OCP) Experience with event streaming platforms such as Kafka or RabbitMQ Hands-on experience with Docker and Kubernetes Experience working with AWS or other cloud platforms Ability to build scalable, reliable, and...

  Job Title: Senior Full Stack Developer (contract) Location: London Hybrid. Travel to the London office 3 days a week Duration: 11 months Contract Start Date: ASAP *note client onboarding takes 6 weeks from offer Day Rate: Competitive (Inside IR35)   Deloitte Working with the Deloitte Associate (Contractor) Programme means we can offer you the opportunity to work on a variation of industry and client related projects. Our aim is to retain the best talent and so when your project end date nears our team of Talent Community Advisors will be working with you to look at alternative projects within the firm that suit your experience should you wish to continue with Deloitte.   The Role We are looking for Senior Full Stack Developers to work in the Technology and Transformation Team at Deloitte. You will work with one of our global financial services clients. This position...

  Job Title: Senior Full Stack Developer (contract) Location: London Hybrid. Travel to the London office 3 days a week Duration: 11 months Contract Start Date: ASAP *note client onboarding takes 6 weeks from offer Day Rate: Competitive (Inside IR35)   Deloitte Working with the Deloitte Associate (Contractor) Programme means we can offer you the opportunity to work on a variation of industry and client related projects. Our aim is to retain the best talent and so when your project end date nears our team of Talent Community Advisors will be working with you to look at alternative projects within the firm that suit your experience should you wish to continue with Deloitte.   The Role We are looking for Senior Full Stack Developers to work in the Technology and Transformation Team at Deloitte. You will work with one of our global financial services clients. This position...

  Job Title: Senior Full Stack Developer (contract) Location: London Hybrid. Travel to the London office 3 days a week Duration: 11 months Contract Start Date: ASAP *note client onboarding takes 6 weeks from offer Day Rate: Competitive (Inside IR35)   Deloitte Working with the Deloitte Associate (Contractor) Programme means we can offer you the opportunity to work on a variation of industry and client related projects. Our aim is to retain the best talent and so when your project end date nears our team of Talent Community Advisors will be working with you to look at alternative projects within the firm that suit your experience should you wish to continue with Deloitte.   The Role We are looking for Senior Full Stack Developers to work in the Technology and Transformation Team at Deloitte. You will work with one of our global financial services clients. This position...

Description We are seeking a passionate Software Engineering Manager with a strong background in modern frontend engineering, particularly React, Next.js, and TypeScript, to provide technical leadership and operate with excellence. Creative, curious, and confident, you will be an integral part of our empowered, self-managing, multi-disciplinary engineering teams -designing, building, releasing, and maintaining high-quality digital products. You will play a key role in shaping and growing a best-in-class frontend engineering capability, establishing modern development practices and building scalable, high-performance web applications. This is an initial 6-month contract (outside IR35) requiring 3 days per week onsite in Paddington, London. Key Accountabilities Team Leadership Build, mentor, and lead a high-performing team of frontend engineers specialising in React, Next.js, and TypeScript. Foster a culture of collaboration, technical excellence, and...

Job Title: Senior Full Stack Developer (contract) Location: London Hybrid. Travel to the London office on 3 days a week Duration: 11 months Contract Start Date: ASAP *note client onboarding takes 6 weeks from offer Day Rate: Competitive (Inside IR35)   Deloitte Working with the Deloitte Associate (Contractor) Programme means we can offer you the opportunity to work on a variation of industry and client related projects. Our aim is to retain the best talent and so when your project end date nears our team of Talent Community Advisors will be working with you to look at alternative projects within the firm that suit your experience should you wish to continue with Deloitte.   The Role We are looking for Senior Full Stack Developers to work in the Technology and Transformation Team at Deloitte. You will work with one of our global financial services clients. This position requires a solid understanding of Development and...

Role Summary   Wagglyn is seeking an experienced OMS / Trading Systems Engineer – Contractor to work with the existing engineering team on the design and implementation of the order management and execution control layer underpinning our low-latency FX trading platform.   This is a hands-on engineering role focused on building the core trading state and execution orchestration layer for a systematic FX trading platform operating across multiple brokers, venues, accounts, and execution routes.   The OMS layer acts as the canonical source of truth for trading state, execution workflow, position attribution, and operational controls across the platform.   You will work closely with the CTO and engineering team to design deterministic, production-ready systems capable of operating reliably under real market conditions.   This role is not suited to generic backend developers or UI-focused engineers.  ...

  Job Title: Full Stack Developer (contract) Location: London Hybrid. Travel to the London office on 3 days a week Duration: 11 months Contract Start Date: ASAP *note client onboarding takes 6 weeks from offer Day Rate: Competitive (Inside IR35)   Deloitte Working with the Deloitte Associate (Contractor) Programme means we can offer you the opportunity to work on a variation of industry and client related projects. Our aim is to retain the best talent and so when your project end date nears our team of Talent Community Advisors will be working with you to look at alternative projects within the firm that suit your experience should you wish to continue with Deloitte.   The Role We are looking for an experienced Full Stack Developers to work in the Technology and Transformation Team at Deloitte. You will work with one of our global financial services clients. This position...

Lead DevOps Engineer (AI- Focused) Mandatory hands-on experience supporting AI/ML or GenAI platforms About Synechron: Synechron is a leading digital transformation consulting firm dedicated to delivering innovative technology solutions within banking, financial services, and insurance. We thrive on engineering excellence, collaboration, and a passion for cutting-edge technologies. Job Location: London (Hybrid - 3 days in the office) Job Summary Are you passionate about making developers' lives easier, faster, and more fulfilling? We're on a mission to supercharge our engineering culture by building a world-class DevOps organization that's the envy of the industry. This is a great opportunity to join a growing company in an innovative and dynamic industry! We are looking for a strong, hands-on Lead DevOps Engineer t o build and maintain a brand-new cloud-based Index platform. You will lead a team of Senior and Junior DevOps Engineers to help us...

Contract - Full Stack Developer (React, Java, Spring) Job description Job Title: Full Stack Developer (Java, Spring, React) - contract Location: London Hybrid. Travel to the London office on 3 days a week Duration: 11 months Contract Start Date: ASAP *note client onboarding takes 6 weeks from offer Day Rate: Competitive (Inside IR35) Deloitte Working with the Deloitte Associate (Contractor) Programme means we can offer you the opportunity to work on a variation of industry and client related projects. Our aim is to retain the best talent and so when your project end date nears our team of Talent Community Advisors will be working with you to look at alternative projects within the firm that suit your experience should you wish to continue with Deloitte. The Role We are looking for an experienced Full Stack Developers to work in the Technology and Transformation Team at Deloitte. You will work with one of our global financial services clients. This position...

About CACI From our headquarters in London, we're busy empowering organisations to make bold, strategic moves with the power of data and technology. Founded in 1975, our operations take place from multiple offices across the UK, Europe and India with over 1600 Full time employees and an annual turnover of £179m. Our expertise spans industries, from retail and education to public sector and transport - delivering intelligent solutions that drive progress and create measurable impact. Whether it's business intelligence, customer marketing, cloud infrastructure, cybersecurity, critical national infrastructure or data management, our approach is never one-size-fits-all. We don't just deliver solutions; we build for the tomorrow's world, all while fostering a culture that allows employees to be their authentic selves and succeed in their careers. About Network Services CACI Network Services is a rapidly expanding specialist IT and Networks consultancy offering a...

Date published 04-May-2026 Req # 22950 Job description   Job Title: Full Stack Developer (Java, Spring, React) - contract Location: London Hybrid. Travel to the London office on 3 days a week Duration: 11 months Contract Start Date: ASAP *note client onboarding takes 6 weeks from offer Day Rate: Competitive (Inside IR35)   Deloitte Working with the Deloitte Associate (Contractor) Programme means we can offer you the opportunity to work on a variation of industry and client related projects. Our aim is to retain the best talent and so when your project end date nears our team of Talent Community Advisors will be working with you to look at alternative projects within the firm that suit your experience should you wish to continue with Deloitte.   The Role We are looking for an experienced Full Stack Developers to work in the Technology and...

  Job Title: Full Stack Developer (contract) Location: London Hybrid. Travel to the London office on 3 days a week Duration: 11 months Contract Start Date: ASAP *note client onboarding takes 6 weeks from offer Day Rate: Competitive (Inside IR35)   Deloitte Working with the Deloitte Associate (Contractor) Programme means we can offer you the opportunity to work on a variation of industry and client related projects. Our aim is to retain the best talent and so when your project end date nears our team of Talent Community Advisors will be working with you to look at alternative projects within the firm that suit your experience should you wish to continue with Deloitte.   The Role We are looking for an experienced Full Stack Developers to work in the Technology and Transformation Team at Deloitte. You will work with one of our global financial services clients. This position...

We are urgently looking for experienced candidates with strong hands-on Java development skills and design experience. While an architect title is not mandatory, we are particularly interested in profiles of senior developers with solid technical expertise. Required Core Skills: - Java - Python - GoLang -Design, develop, and maintain high-quality Java applications. -Write clean, efficient, and well-documented code. -Perform code reviews and optimize existing codebases. -Ensure application performance and reliability. -Develop and maintain automated tests to ensure code quality. -Work with CI/CD pipelines to streamline the development and deployment process. Job Types: Full-time, Freelance Pay: £350.00-£370.00 per day Schedule: Monday to Friday Experience: Java: 7 years (required) Python: 3 years (required) Go: 2 years (required)

Job Title: Full Stack Developer (Java, Spring, React) - contract Location: London Hybrid. Travel to the London office on 3 days a week Duration: 11 months Contract Start Date: ASAP *note client onboarding takes 6 weeks from offer Day Rate: Competitive (Inside IR35)   Deloitte Working with the Deloitte Associate (Contractor) Programme means we can offer you the opportunity to work on a variation of industry and client related projects. Our aim is to retain the best talent and so when your project end date nears our team of Talent Community Advisors will be working with you to look at alternative projects within the firm that suit your experience should you wish to continue with Deloitte.   The Role We are looking for an experienced Full Stack Developers to work in the Technology and Transformation Team at Deloitte. You will work with one of our global financial services clients. This position requires an...

Time commitment: Freelance project lasting around 3 to 5 months Location: Hybrid or Remote Reporting to: VP of Technology, Avishai Gurt   About Paloma   Paloma’s mission is to make children’s autism and ADHD assessments and care available on the NHS within 4 weeks of GP referral. We are making this possible by setting a new standard for high-quality autism and ADHD care, building great software & AI tools, and investing in clinicians' learning & development.   Mark and Darshak founded Paloma due to their frustration that families are waiting 4-10 years for NHS children’s autism and ADHD assessments. This crisis in NHS children’s neurodevelopmental services has been highlighted by the Children’s Commissioner for England here:...