13 of 13 Part-Time Backend Developer Jobs in the City of London

Location: London EC2 (Office-based, 5 days pw - Monday to Friday) Salary: £70,000 – £80,000 + bonus Type: Full-time, Permanent Backend Java Developer Overview A leading FCA-regulated financial technology firm is seeking an experienced Backend Java Developer to join its growing team. This More ❯

excel in a dynamic, high-energy environment. Join our team and help shape the future of AI . Location and Legalities This full-time Backend Web Developer position is based onsite in our brand-new Ultralytics office in London, UK. Applicants must have legal authorization to work in … the UK, as Ultralytics does not provide visa sponsorship. What You'll Do As a Backend Web Developer at Ultralytics, you will be the architect behind the scalable, high-performance services that power Ultralytics HUB . You will build the backbone that supports our global community in training … and AI research teams to deliver seamless, end-to-end features for our cutting-edge AI models . ️ Skills and Experience 5+ years of backend development experience, with a strong portfolio of building scalable, production-grade web services. Expert-level proficiency in Python and significant experience with modern web More ❯

an agentic AI system that seamlessly integrates into clients' systems, automating compliance and portfolio risk analysis processes Job Summary: We are seeking a skilled Backend Developer with 2-5 years experiences to join our dynamic team. In this role, you will be instrumental in designing, building, and maintaining … the backend infrastructure that powers our SaaS platform. You will work closely with cross-functional teams to ensure seamless integration and the optimal performance of our systems. Responsibilities: Work closely with our data and engineering teams to understand and improve the current code repository and dataset structures. Build and … data integrity and security through the implementation of best practices and industry standards. Collaborate with frontend developers, data scientists, and product managers to integrate backend services with AI/ML models and frontend applications. Implement data processing pipelines to handle large volumes of financial data efficiently. Write clean, maintainable More ❯

Backend Developer – Python £650/day – 6 months – Inside IR35 – 3 days onsite (London) Python – Kafka – AWS – TypeScript – Commodities Trading You'll be working for a leading energy trading business, building out a modern post-trade platform that's genuinely pushing boundaries – live PnL, intraday position reporting, and … that backs its tech, delivers fast, and builds for the long-term. The must-haves: Strong Python experience (hands-on and recent) Experience building backend services in a product team Kafka or other message queue systems Comfortable working in fast-moving agile squads Experience in commodities or trading (preferred More ❯

accessible and commission-free, they’re genuinely reshaping how everyday people build their financial futures. They’re now looking for both Senior and Staff Backend Engineers to join the team. The stack is primarily TypeScript and Node.js , but they’re open to strong backend engineers from any background More ❯

healthtech, and telecom, and a $90B+ market in sight, we're scaling fast in 2025 and beyond. The Role We’re looking for a Backend Engineer (Kotlin) to evolve and scale the control-plane of our SaaS platform. With customer adoption climbing, we need extra fire-power to extend … core services and keep pace with new feature demand. Reporting to the Backend Team Lead , you’ll build services that power everything the UI depends on. You’ll work closely with Product Management on feature design and pair with frontend engineers. The role offers plenty of scope to shape More ❯

a permanent basis working with their Central Government clients. In order to be successful, you will have the following experience Highly experienced back end developer, with experience in working on Government or Defence applications (DV Cleared) Experienced developer within Java, TypeScript, JavaScript and/or Python Build solutions More ❯

SThree are pleased to announce we’re recruiting for a talented Senior Java Back End Developer to join our excellent team, based in Bank, London. The Senior Java Back End Developer will design, develop, test and support capabilities in our digital experience platform to create competitive advantage for More ❯

UK remote 12-month Contract £36 an hour Inside IR 35 PAYE + holiday benefit Back End Developer (Golang expert) Duties You will work in small teams in a highly collaborative way, use the latest technologies and enjoy seeing the direct impact from your work. In teams, you will More ❯

Role : Senior Backend Engineer Salary range : £80,000 – £90,000 Location : Hybrid, 2 days pw, London Tech stack includes: Node.js, TypeScript, PostgreSQL, AWS As a Senior Backend Engineer, you’ll be building and scaling the core systems that power payments for thousands of small businesses across the UK. … business owners. You'll have significant influence over our architecture and technical decisions as we scale our platform. Essentials for this role: 5+ years backend development experience, with Node.js and TypeScript Strong understanding of distributed systems, APIs, and microservices Experience working with relational databases, particularly PostgreSQL Familiarity with cloud More ❯

Role – Back-End Developer Office travel – Hybrid (3 Days a week in the office) Location – Central London Salary – £80,000 - £90,000 + Benefits Infinite Talent has partnered with a renewable energy start-up backed by a global business to recruit for two Back-End Developers on a permanent More ❯

Backend Engineer London Hybrid £80,000-£95,000 + bonus and benefits We’re working with a rapidly growing tech for good company that is transforming how data, automation, and smart integrations shape the future of digital infrastructure. Their platform optimises real-time operations, connecting users with seamless, intelligent … technology solutions. They are looking for a Senior Backend Engineer with deep expertise in Kotlin (or JVM and willing to step into Kotlin specifically) to help scale and enhance their high-performance systems. This is an opportunity to work with modern backend architecture, collaborating with top-tier engineers … in a fast-moving, product-focused environment. Responsibilities as a Backend Engineer: Contribute to the businesses technology strategy and architecture Ship resilient and well tested production code Collaborate with different teams to deliver value that aligns to business objectives Mentor and coach more junior members of the team Continuously More ❯

Back-end Node.js Developer | Inside IR35 | Remote - UK | 6 Month Contract Our client a multinational and respected consultancy is hiring for a Back-end Node.js Developer with expertise in Node.js and Google Kubernetes for a new project in the Communication Sector. Duration: 6 Months + Extensions Location: Remote More ❯