backend java developer jobs in City of Westminster

You will be responsible for building scalable, high-performance Back End systems that power their banking platform.

A leading FinTech innovator is shaping the future of financial markets - across traditional finance and crypto - with cutting-edge trade surveillance technology. Their mission is to protect investors, enhance transparency, and ensure compliance in some of the world's most dynamic markets. Trusted by regulators and institutions worldwide, their systems monitor over a trillion events every single...

Manages a team of developers, overseeing software delivery for front-office trading systems, focusing on Java and collaborating with stakeholders.

Excellent opportunity to join a growing and award winning SaaS organisation headquartered in Belfast. My client have won various awards for innovation and support. Due to demand they have a new opportunity for a talented Android developer to join the team situated all over Ireland North and South. On offer - Salary £60k - £70k - D.O.E - Remote working options - Work from any where in Ireland -...

About Aero A digital experience company, we sit at the intersection of insights, creativity and technology, crafting digital experiences that transform business performance. We’re a small, fully remote team with big ambitions. We work hands-on with our clients, giving our teams genuine ownership of their work. Every project you touch will be seen by thousands of people and will directly...

We believe in better. And we make it happen. Better content. Better products. And better careers. Working in Tech, Product or Data at Sky is about building the next and the new. From broadband to broadcast, streaming to mobile, SkyQ to Sky Glass, we never stand still. We optimise and innovate. We turn big ideas into the products, content and services millions of people love. And we do it all...

Job DescriptionWhite Collar Factory (95009), United Kingdom, London, London Senior Software Development Engineer - Services About this roleWe are seeking a Senior Software Engineer who can walk in the shoes of our users, communicate & collaborate with teams in Business, Technology and Operations, bringing a passion for using software and technology to create impactful solutions. To be successful...

You will be working with arguably the most stable teams in crypto, and at the bleeding-edge of finance. Package incudes base salary (Up to 180,000 Euros), + RSU's + Bonus (8-15%) This opportunity is available in the below jurisdictions, the client is looking to hire people full-time (Not through B2B contract) and does not sponsor visas.

For more than two decades, Orange Logic has empowered a wide range of clients with its digital asset management system, Orange Logic Platform. We’ve worked with almost every industry, from Finance to NGOs, Media giants to educational institutions, securing and organizing their assets. This role will enhance Orange Logic’s software by participating in the design, development, maintenance and...

Leading Sustainable E-Commerce | 35 Million Users | Mid & Senior Back End Engineers | TypeScript/Node/AWS | Up to £100K + Bonus | REMOTE (UK) or 1 Day Per Week (LDN) Company Our client is an extremely well known, digital marketplace focused on sustainable ecommerce. With over 35 million of active users globally, they’re redefining how people buy and sell second-hand fashion, aiming to make the...

Senior Software Engineer - Backend & Data | Fully Remote (UK) Founding Engineer | Python | GCP | Terraform | Event-Based Systems | Data Pipelines An innovative, mission-driven LegalTech SaaS start-up is looking for a Senior Product Engineer (Backend & Data) with deep experience in Python, Product development, and Data engineering. Role Information: - Salary: Up to £100,000 (DOE) + Equity -...

Manage a team of developers to deliver front office derivatives technology. Requires Java, people management, and experience with front office trading systems.

Senior Python Engineer | Fully Remote | High-Growth Startup (AI / Data / Cloud) Join one of the most exciting early-stage startups of the year — backed by previous huge success, led by an exceptional founding team, and already showing incredible product-market fit. This is a rare opportunity to get in early, take real ownership, and build the foundations of a next-generation platform at scale....

React Native Technical Lead – EdTech | Remote (UK) | Up to £85,000 Location: Fully remote (within the UK) Salary: Up to £85,000 + benefits Employment Type: Full-time, permanent Are you a hands-on React Native expert ready to shape the future of digital learning? We are working with a UK-based EdTech company on a mission to make high-quality education accessible to everyone — and are looking...

Job Title: Software Engineer (AI HealthTech) Client: AI HealthTech Scale-Up – Backed by Top-Tier Investors, Led by World-Class Engineers Salary: Up to £100k + Bonus + Equity Location: Remote (UK-based) with an optional Holborn office Sells: Work on cutting-edge AI systems that power healthcare innovation at scale. Full remote flexibility across the UK, total ownership of greenfield projects,...

You will develop and design data pipelines, data models, backend APIs and an array of customer facing data services.

Role/Job Title: PSA Engineer - GenerationWork Location: Edinburgh / Remote The Role Your Responsibilities: Electrical transmission modeling, EMS Application Engineer, GE PowerOn Reliance / XA21, GE eTerra Platform, Power System Applications.Hands-on experience with Energy Management System (EMS) / Generation Monitoring and Control applications.Software development experience with C / C++ / Java...

You will balance quality, latency, cost, and governance, collaborating closely with solution architects and client stakeholders to transform use cases into robust, observable AI services. Responsibilities: Develop LLM-powered applications-including assistants, agents, summarization, classification, extraction, and workflow automation-utilizing OpenAI/Azure OpenAI and open-weight models as needed.

You will be instrumental in shaping our technical direction, driving the evolution of our APIs, ensuring our services are resilient, scalable and secure within a cutting-edge, cloud-native environment (Helm, Kubernetes). The DeliverablesDesign and build sophisticated, scalable GraphQL APIs and backend services using TypeScript and Node.

We believe in better. And we make it happen. Better content. Better products. And better careers. Working in Tech, Product or Data at Sky is about building the next and the new. From broadband to broadcast, streaming to mobile, SkyQ to Sky Glass, we never stand still. We optimise and innovate. We turn big ideas into the products, content and services millions of people love. And we do it all...