101 to 125 of 375 API Development Jobs in the UK

SÜD Group Future in your hands Want to view other available job postings? Bachelor's degree in Computer Science or equivalent experience. C#/.NET: Extensive experience in C# development, including strong understanding of object-oriented principles, asynchronous programming, and .NET framework/Core. Blazor: Proven experience developing web applications using Blazor and related technologies. Telerik Components: Demonstrable experience … using Telerik UI components. Python: Solid understanding of Python and experience developing serverless functions using Azure Functions. REST API Development: Proficiency in designing and implementing RESTful APIs using C# and .NET. Azure DevOps: Hands-on experience with Azure DevOps. Software Development Lifecycle (SDLC): Understanding of agile methodologies. Problem-Solving Skills: Excellent analytical and problem-solving skills. Communication … you could also be entitled to other benefits e.g. a Company Car or Car Allowance, Private Medical Insurance or a Relocation Package. We are dedicated to your growth and development Our training programmes, mentorship, exchange programmes and funding for professional membership subscriptions, courses and certifications aim to support your career advancement. Our global footprint also means: Short-term secondment More ❯

our employees to get involved in decision making as we continue to grow and scale. We give all our employees share options so they participate in the growth and development of the business. We offer a combination of remote and office (London based) working, weekly team lunches and plenty of office snacks! For more information, please visit our website … edge data visualization projects, leveraging modern technologies and large-scale datasets. You'll be part of a dynamic team that values innovation, learning, and collaboration. Required Skills & Experience Web Development: Proficient in React and TypeScript. Data Visualization: Experience with libraries such as Highcharts and D3.js. Testing: Familiarity with Jest and Playwright or similar testing frameworks. REST APIs: Strong understanding … analytics projects. Experience with data engineering tools (DuckDB, PySpark, etc.). Knowledge of automated testing frameworks (Playwright, Cypress). Experience of WebAssembly. Python programming experience for data manipulation or API development. Use of AI for creating visualisations. Soft Skills: Exceptional leadership skills with the ability to lead a team of software developers effectively. Excellent problem-solving skills and ability More ❯

Technical Lead – Java Spring Boot – Must have Mobile App Development/Modernisation Location: Hybrid, 1 day a week in London office A leading enterprise organisation that specialises in AI-First solutions is seeking a seasoned Technical Lead with deep expertise in Java Spring Boot, microservices architecture, and solution design to drive the backend engineering strategy for its platform engineering … function. The ideal candidate brings a blend of strong technical leadership, architectural insight, and hands-on development capability, alongside experience collaborating across cross-functional teams. This role involves leading the development of scalable, secure, and maintainable backend systems, especially those supporting mobile ecosystems. Prior experience in the banking or financial services domain is highly advantageous. Must have experience … with API gateways and mobile app development/modernisation Key Responsibilities: Design and develop high-performance, secure, and scalable backend systems using Java, Spring Boot, and modern architectural patterns. Lead the development of RESTful APIs and microservices, ensuring alignment with mobile platforms and business objectives. Integrate with API Gateway solutions (e.g., Kong, Apigee, AWS API More ❯

Technical Lead – Java Spring Boot – Must have Mobile App Development/Modernisation Location: Hybrid, 1 day a week in London office A leading enterprise organisation that specialises in AI-First solutions is seeking a seasoned Technical Lead with deep expertise in Java Spring Boot, microservices architecture, and solution design to drive the backend engineering strategy for its platform engineering … function. The ideal candidate brings a blend of strong technical leadership, architectural insight, and hands-on development capability, alongside experience collaborating across cross-functional teams. This role involves leading the development of scalable, secure, and maintainable backend systems, especially those supporting mobile ecosystems. Prior experience in the banking or financial services domain is highly advantageous. Must have experience … with API gateways and mobile app development/modernisation Key Responsibilities: Design and develop high-performance, secure, and scalable backend systems using Java, Spring Boot, and modern architectural patterns. Lead the development of RESTful APIs and microservices, ensuring alignment with mobile platforms and business objectives. Integrate with API Gateway solutions (e.g., Kong, Apigee, AWS API More ❯

clean, modern C# code. What you'll be working with: We're looking for developers with solid core engineering skills and a strong background in modern C# and .NET development , including: Core C# & .NET Skills Hands-on experience with C# (latest versions preferred) Deep knowledge of .NET Core/.NET 6/7/8 for building scalable APIs … Strong grasp of OOP principles and design patterns API Development Building and maintaining RESTful APIs Solid understanding of HTTP protocols, status codes, headers, etc. API documentation using tools like Swagger/OpenAPI Legacy Systems Exposure to or experience with WCF services - we still support some older systems, so comfort working with a mix of modern and legacy … tech is key DTOs and model binding Security API authentication and authorization best practices Knowledge of OAuth2, JWT, OpenID Connect Secure coding practices for exposed endpoints Integration & Communication Consuming third-party APIs (REST/SOAP) Async/await, tasks, and non-blocking design Database Integration Hands-on with Entity Framework Core or similar ORM Confident writing SQL and working More ❯

rebuild their software environment. This role is central to developing web-based applications and systems that support strategic business goals. The ideal candidate is highly skilled in Azure cloud development, experienced in Agile and DevOps environments, and capable of leading development teams. Duties and Responsibilities: Software development, evaluating and improving codebases. Implement long-term development strategies … with incremental improvements. Lead and mentor software engineers to enhance performance. Refine development processes, tools, and standards for efficiency and quality. Manage competing priorities and make decisions under pressure. Collaborate with technical and non-technical stakeholders. Stay updated on industry standards, including version control, code reviews, testing, and CI/CD. Apply Agile methodologies in development practices. Required … Skills: Extensive software development experience with a proven record of improving codebases. Skilled in C#, .NET, Azure, and SQL. Strong background in API development and provider application implementation. Capable of shaping long-term strategies while managing incremental improvements. Proven leader with experience mentoring teams and driving performance. Experienced in optimising development tools, processes, and standards. Strong More ❯

clean, modern C# code. What you’ll be working with: We’re looking for developers with solid core engineering skills and a strong background in modern C# and .NET development , including: Core C# & .NET Skills Hands-on experience with C# (latest versions preferred) Deep knowledge of .NET Core/.NET 6/7/8 for building scalable APIs … Strong grasp of OOP principles and design patterns API Development Building and maintaining RESTful APIs Solid understanding of HTTP protocols, status codes, headers, etc. API documentation using tools like Swagger/OpenAPI Legacy Systems Exposure to or experience with WCF services — we still support some older systems, so comfort working with a mix of modern and legacy … tech is key Data Handling JSON serialization/deserialization DTOs and model binding Security API authentication and authorization best practices Knowledge of OAuth2, JWT, OpenID Connect Secure coding practices for exposed endpoints Integration & Communication Consuming third-party APIs (REST/SOAP) Async/await, tasks, and non-blocking design Database Integration Hands-on with Entity Framework Core or similar More ❯

clean, modern C# code. What you’ll be working with: We’re looking for developers with solid core engineering skills and a strong background in modern C# and .NET development , including: Core C# & .NET Skills Hands-on experience with C# (latest versions preferred) Deep knowledge of .NET Core/.NET 6/7/8 for building scalable APIs … Strong grasp of OOP principles and design patterns API Development Building and maintaining RESTful APIs Solid understanding of HTTP protocols, status codes, headers, etc. API documentation using tools like Swagger/OpenAPI Legacy Systems Exposure to or experience with WCF services — we still support some older systems, so comfort working with a mix of modern and legacy … tech is key Data Handling JSON serialization/deserialization DTOs and model binding Security API authentication and authorization best practices Knowledge of OAuth2, JWT, OpenID Connect Secure coding practices for exposed endpoints Integration & Communication Consuming third-party APIs (REST/SOAP) Async/await, tasks, and non-blocking design Database Integration Hands-on with Entity Framework Core or similar More ❯

functional and compliance requirements, and solutions are well designed with maintainability/ease of integration and testing built-in from the outset. Job expectations include a strong knowledge of development and testing practices common to the industry and design and architectural patterns. Responsibilities: Codes solutions and unit test to deliver a requirement/story per the defined acceptance criteria … develops, and modifies architecture components, application interfaces, and solution enablers while ensuring principal architecture integrity is maintained Mentors other software engineers and coach team on Continuous Integration and Continuous Development (CI-CD) practices and automating tool stack Executes story refinement, definition of requirements, and estimating work necessary to realize a story through the delivery lifecycle Performs spike/proof … activities Designs, develops, and maintains automated test suites (integration, regression, performance) Position Summary .NET Software Engineer III is a member of the Wealth Management Shared Technology team and performs development and support of highly scalable, most resilient and reusable shared capabilities across enterprise. Additional responsibilities include: API/Webservice design and development formiddle-tiercapabilities,includingRedis in-memorydatabase More ❯

including offshore teams and contractors. Oversee software architecture, ensuring seamless integration with various platforms. Gather and analyse requirements, refining features and technical solutions. Lead the estimation process and ensure development work is accurately scoped. Debug existing code, maintain system performance, and drive best coding practices. Manage defects and oversee their resolution across the development team. Experience: 4+ years … experience in software engineering, with a strong focus on Java development. Experience leading and/or mentoring technical teams within fast-paced, agile environments. Expertise in microservices architecture, REST API development, and security. Strong DevOps knowledge, particularly with Ansible or Jenkins pipelines. Proficiency in object-oriented design, relational databases, and MongoDB. Experience with version control (GIT preferred) and More ❯

new asset management system—and they’re looking to bring experienced Back-End or Full Stack Developers on board to drive this transformation. As a key part of the development team, you’ll be involved in architecting and delivering robust, scalable backend solutions using PHP (Laravel), MySQL, and modern frontend technologies. You’ll be joining a collaborative and agile … environment where autonomy and technical input are both valued and encouraged. What you’ll be working with: PHP (Laravel) and MVC frameworks MySQL Backend API development (REST) HTML, CSS, JavaScript, Bootstrap Vue.js or similar JavaScript frameworks Azure DevOps, CI/CD pipelines Linux-based environments What we’re looking for: 3–6 years’ experience in a full stack … React, Node.js, Angular, or additional modern JS frameworks This is an exciting opportunity to work on a greenfield project with long-term impact, using a modern stack and best development practices. On offer is a salary of £60,000 plus excellent benefits, flexible working, and the chance to be part of something genuinely rewarding. Interested? Apply now or get More ❯

new asset management system—and they’re looking to bring experienced Back-End or Full Stack Developers on board to drive this transformation. As a key part of the development team, you’ll be involved in architecting and delivering robust, scalable backend solutions using PHP (Laravel), MySQL, and modern frontend technologies. You’ll be joining a collaborative and agile … environment where autonomy and technical input are both valued and encouraged. What you’ll be working with: PHP (Laravel) and MVC frameworks MySQL Backend API development (REST) HTML, CSS, JavaScript, Bootstrap Vue.js or similar JavaScript frameworks Azure DevOps, CI/CD pipelines Linux-based environments What we’re looking for: 3–6 years’ experience in a full stack … React, Node.js, Angular, or additional modern JS frameworks This is an exciting opportunity to work on a greenfield project with long-term impact, using a modern stack and best development practices. On offer is a salary of £60,000 plus excellent benefits, flexible working, and the chance to be part of something genuinely rewarding. Interested? Apply now or get More ❯

teams to implement new services for our 3D Cloud platform. • Collaborate directly with our enterprise customers to deliver fully functional B2B solutions with great user experiences. • Stay current on development technologies and make best practice recommendations for coding standards and solution choices, with a particular focus on security and data privacy. • Improve code quality through automation and performing code … full application stack Qualifications and Skills • BS Degree in Computer Science, Computer Engineering or similar technical field of study, or equivalent practical experience • 5+ years experience in full-stack development including front-end frameworks and back-end services (eg: Angular, React, Spring Boot, Hibernate) •3+ years experience in cloud platforms and IaC • Strong Coding Skills in Java, Python, Typescript … engineering teams and pick up new technology quickly • Experience with observability tools and a track record of improving system reliability • Knowledge of software engineering standard practices and architecture, especially API development and enterprise integration patterns. Preferred Qualifications • GCP experience • Understanding of containerization technologies • Experience with front-end web application development • Experience working in the Retail, Manufacturing, or More ❯

a highly experienced .NET Architect to drive the technical design and implementation of a next-generation Treasury platform. This is a key role responsible for shaping system architecture, guiding development teams, and ensuring the scalability, robustness, and performance of mission-critical trading and treasury systems. Key Requirements: INSIDE IR35 Hybrid working: 3 days onsite in London Must have Capital … as Order Management Systems (OMS), Execution Management Systems (EMS), pricing engines, and compliance modules. Conduct architecture and code reviews, ensuring alignment with enterprise standards and industry best practices. Mentor development teams and help drive delivery within an Agile framework. Essential Skills & Experience: Proven background in .NET architecture roles within capital markets, investment banking, or other financial services environments. Deep … programming, and real-time distributed systems. Strong understanding of treasury operations, fixed income, FX, and derivatives workflows. Solid experience with SQL Server, messaging systems (e.g., RabbitMQ, Service Bus), and API development (REST, FIX). Experience in cloud-native architecture, ideally with Microsoft Azure (Functions, Logic Apps, Cosmos DB, Blob Storage, Service Bus). Familiarity with Order Management Systems More ❯

from trade capture and pricing to live risk, P&L tracking, and position keeping. You will join the client's internal team directly to help strengthen their in-house development capabilities and drive platform growth. What you'll do: Design, develop, test, and deploy solutions for the platform. Write clean, maintainable code with a strong focus on unit testing. … Maintain coding standards, guidelines, and best practices across the team. Promote high-quality documentation throughout the development process. Contribute to platform quality, infrastructure, and release process management. Provide technical support to developers and business stakeholders. Prioritize security, maintainability, scalability, code quality, and future-proofing. Assist with cloud infrastructure maintenance, monitoring, and alerting. Manage multiple development threads, including feature … development, refactoring, bug fixing, client customizations, and data mapping. What we're looking for: Strong technical background with experience collaborating with distributed teams. Excellent communication, analytical skills, and a collaborative mindset. Highly self-organized and technically driven. Solid experience with C#, .NET Core, and modern cloud environments (preferably Azure). Hands-on experience with frontend development using React More ❯

Company and Role Overview Origo is a forward-thinking, growing Fintech company with a 30+ year history and a mission to connect the Financial Services industry. The Development team is responsible for building and maintaining Origo’s expanding number of services. The team is currently looking for an experienced C# developer (ideally with some experience of JavaScript and/… Develop high quality, fit-for-purpose code that meets the business, architectural and security requirements. Design and conduct unit test plans to ensure high quality levels. Create and maintain development artefacts and documentation for existing services. Create detailed technical and design specifications in response to new business concepts/outline specifications. Provide accurate estimates for all development activities … to assist the Technical Leads with estimating project costs/timescales. Assist in the delivery of all development activities to the budget, timescales and quality criteria of the relevant development project or maintenance release through the complete project life cycle (and during the post release warranty period). Ensure ongoing awareness of current and emerging technologies and suggest More ❯

Role We're looking for a Senior Fullstack Developer who can take features from concept to production with confidence. You'll have the real opportunity to own the full development lifecycle. Including planning the technical architecture to building an MVP, refining it through iteration, tackling the odd bug, and ensuring we're ready for launch! You'll also play … re looking for: Experience working on live, user-facing products. Strong problem-solving skills with a growth mindset and the ability to iterate quickly. Deep expertise in modern web development technologies: TypeScript, ReactJS, NextJS, and NodeJS. Experience working with CSS, component libraries and design systems (ChakraUI, Tailwind or similar). Some knowledge of GraphQL for API development … chance to get together somewhere awesome, connect, and plan big things. Weekly gaming sessions - you don't have to but we believe a little friendly competition never hurts. Learning & development budget - whether it's courses, books, or training, we've got you covered. Equity Options - We offer all employees ownership of the company to ensure the entire team is More ❯

team to integrate TypeScript and React into our target architecture. Over time, the focus of this role will shift from maintaining legacy PHP systems to contributing directly to the development and optimization of our modernized technology stack. This is an opportunity to join the UK's number one investment services company, looking after over £149.7bn billion in assets on … quality, security, performance and CI/CD processes. Responsible in helping to document solutions and write ADRs Demonstrate a willingness to learn and further technologies & techniques embraced by the development team. Cultivate strong working relationships both within working squad and in HL as a whole. Actively participating in working groups and communities of practice designed to support the development … Jest, Cypress, Backstop). Enjoys upskilling others in a team - you prioritise sharing knowledge Experience with CI/CD and Trunk Based Development. Understanding of Microservices & principles of RESTful API development, including structuring, documenting, versioning, testing and stubbing/mocking. Understanding of event driven architecture. Experience performing code reviews. Experience operating within Agile framework. Aware of website performance More ❯

team to integrate TypeScript and React into our target architecture. Over time, the focus of this role will shift from maintaining legacy PHP systems to contributing directly to the development and optimization of our modernized technology stack. This is an opportunity to join the UK's number one investment services company, looking after over £149.7bn billion in assets on … quality, security, performance and CI/CD processes. Responsible in helping to document solutions and write ADRs Demonstrate a willingness to learn and further technologies & techniques embraced by the development team. Cultivate strong working relationships both within working squad and in HL as a whole. Actively participating in working groups and communities of practice designed to support the development … Jest, Cypress, Backstop). Enjoys upskilling others in a team - you prioritise sharing knowledge Experience with CI/CD and Trunk Based Development. Understanding of Microservices & principles of RESTful API development, including structuring, documenting, versioning, testing and stubbing/mocking. Understanding of event driven architecture. Experience performing code reviews. Experience operating within Agile framework. Aware of website performance More ❯

team to integrate TypeScript and React into our target architecture. Over time, the focus of this role will shift from maintaining legacy PHP systems to contributing directly to the development and optimization of our modernized technology stack. This is an opportunity to join the UK's number one investment services company, looking after over £149.7bn billion in assets on … quality, security, performance and CI/CD processes. Responsible in helping to document solutions and write ADRs Demonstrate a willingness to learn and further technologies & techniques embraced by the development team. Cultivate strong working relationships both within working squad and in HL as a whole. Actively participating in working groups and communities of practice designed to support the development … Jest, Cypress, Backstop). Enjoys upskilling others in a team - you prioritise sharing knowledge Experience with CI/CD and Trunk Based Development. Understanding of Microservices & principles of RESTful API development, including structuring, documenting, versioning, testing and stubbing/mocking. Understanding of event driven architecture. Experience performing code reviews. Experience operating within Agile framework. Aware of website performance More ❯

team to integrate TypeScript and React into our target architecture. Over time, the focus of this role will shift from maintaining legacy PHP systems to contributing directly to the development and optimization of our modernized technology stack. This is an opportunity to join the UK's number one investment services company, looking after over £149.7bn billion in assets on … quality, security, performance and CI/CD processes. Responsible in helping to document solutions and write ADRs Demonstrate a willingness to learn and further technologies & techniques embraced by the development team. Cultivate strong working relationships both within working squad and in HL as a whole. Actively participating in working groups and communities of practice designed to support the development … Jest, Cypress, Backstop). Enjoys upskilling others in a team - you prioritise sharing knowledge Experience with CI/CD and Trunk Based Development. Understanding of Microservices & principles of RESTful API development, including structuring, documenting, versioning, testing and stubbing/mocking. Understanding of event driven architecture. Experience performing code reviews. Experience operating within Agile framework. Aware of website performance More ❯

team to integrate TypeScript and React into our target architecture. Over time, the focus of this role will shift from maintaining legacy PHP systems to contributing directly to the development and optimization of our modernized technology stack. This is an opportunity to join the UK's number one investment services company, looking after over £149.7bn billion in assets on … quality, security, performance and CI/CD processes. Responsible in helping to document solutions and write ADRs Demonstrate a willingness to learn and further technologies & techniques embraced by the development team. Cultivate strong working relationships both within working squad and in HL as a whole. Actively participating in working groups and communities of practice designed to support the development … Jest, Cypress, Backstop). Enjoys upskilling others in a team - you prioritise sharing knowledge Experience with CI/CD and Trunk Based Development. Understanding of Microservices & principles of RESTful API development, including structuring, documenting, versioning, testing and stubbing/mocking. Understanding of event driven architecture. Experience performing code reviews. Experience operating within Agile framework. Aware of website performance More ❯

team to integrate TypeScript and React into our target architecture. Over time, the focus of this role will shift from maintaining legacy PHP systems to contributing directly to the development and optimization of our modernized technology stack. This is an opportunity to join the UK's number one investment services company, looking after over £149.7bn billion in assets on … quality, security, performance and CI/CD processes. Responsible in helping to document solutions and write ADRs Demonstrate a willingness to learn and further technologies & techniques embraced by the development team. Cultivate strong working relationships both within working squad and in HL as a whole. Actively participating in working groups and communities of practice designed to support the development … Jest, Cypress, Backstop). Enjoys upskilling others in a team - you prioritise sharing knowledge Experience with CI/CD and Trunk Based Development. Understanding of Microservices & principles of RESTful API development, including structuring, documenting, versioning, testing and stubbing/mocking. Understanding of event driven architecture. Experience performing code reviews. Experience operating within Agile framework. Aware of website performance More ❯

come up with creative solutions resulting in ground-breaking impact for a wide network of clients. Our culture of evolution and empathy centres on long-term career growth and development opportunities in an environment that embraces your unique skills and experience. We offer: Regular and frequent promotion and progression opportunities to ensure you can drive and develop your career … tools, techniques, and products our clients demand today. You'll work with clients, co-creating solutions to major real-world challenges by translating system requirements into the design and development of customized systems in an agile environment. In your role you may be responsible for: Use IBM's Design Thinking to create products that provide a great user experience … to deliver high-quality solutions. Documentation: Create comprehensive technical documentation for APIs architecture and deployment processes. Required education None Preferred education Bachelor's Degree Required technical and professional expertise API Development: Design develop and maintain robust scalable APIs using modern frameworks and technologies. Azure Logic Apps: Configure and integrate Azure Logic Apps to enable seamless workflows and business More ❯

Java Developer - GCP - API Development - Platform Redesign - InsideIR35 - Hybrid We're looking for a Java Developer with strong API development expertise to join a high-impact transformation programme. This role is central to a major replatforming initiative, where legacy applications built on the Kony platform and JavaScript are being modernised into a React-based architecture to … Responsibilities Design, develop, and maintain robust, scalable APIs in Java to support the new React front-end. Collaborate closely with front-end developers, architects, and product teams to align API functionality with UI/UX goals. Refactor and modernise existing back-end services to align with the new architecture. Ensure high performance, security, and reliability of API endpoints. … Participate in code reviews, testing, and continuous integration processes. Skills & Experience Strong commercial experience in Java (8+) and RESTful API development . Google Cloud Platform - GCP - ESSENTIAL Proven track record of supporting front-end refactoring or replatforming projects . Experience working with modern JavaScript frameworks , ideally React (collaboratively). Familiarity with legacy platform migration Solid understanding of microservices More ❯