25 of 25 API Design Jobs in London

integration layer behind a new generation of AI-powered products. This is a genuinely full-stack engineering role, combining production-grade backend development, API design, AI integrations and frontend engineering. You'll work across the full application lifecycle, designing the services and interfaces that connect AI capabilities … products customers and colleagues use every day. You'll play a key role in building MCP integrations, agent-to-agent connectivity and robust API services, while also developing responsive, accessible interfaces in React and TypeScript. What you'll be doing Own the application and integration layer of AI products ...

architecture of a ledger-based post-trade platform. You'll start hands-on as a senior engineer, and take on increasing ownership of system design, technical direction, and solution architecture as you grow into the role. Why This Role You'll have real influence in a small, high-calibre … genuine voice in product and architectural decisions. Expect a fast learning curve across technology, regulation, and market structure. What You'll Do Architecture & System Design Design secure, scalable distributed systems for regulated environments Define and evolve system architecture, APIs, and integration patterns Apply sound software design patterns ...

play a key part in driving the adoption of AI across engineering, leveraging emerging technologies and embedding AI-native workflows to improve how they design, build, and deliver software. This role is predominantly hands-on, with around 2030% of time on technical leadership: architecture, mentoring, and shaping … generated code to our standards for security, reliability, and cost-efficiency (FinOps). These are first-class concerns in agentic pipelines, not afterthoughts. Design, build, and operate software across our platform, applying the same rigour to AI-augmented work as to anything else you ship. Embed deeply with Product ...

lead the next phase of our technology transformation journey to create great products and services for the organisation. Main Responsibilities Responsible for the overall design and solution architectureinvolvinglargedata. Lead and maintain key design decisions and existing solution architecture documents. Demonstrate a Product delivery mindset, and drive capabilities … existing eCommerce and data infrastructure for scalability and expansion. Skills: Detailed knowledge and previous experience with AI and Claude. Strong understanding of architecture, discovery, design and delivery of Enterprise, Cloud and Security technologies, preferably in a Microsoft technology stack. C# .NET Core, REST API Design and Development ...

data services, and cloud platforms. You will own end-to-end integration architecture, champion modern engineering standards, and guide engineers through best practices in API design, cloud-native development, and scalable integration patterns. This is a hands-on leadership role, ideal for someone who enjoys coding, problem-solving … steering technical direction while mentoring engineers and collaborating with product, data, and platform teams. What You'll Be Doing Lead the design, development, and delivery of integration solutions across a diverse technology ecosystem Develop secure, scalable APIs, services, and messaging-based integrations Champion best practices in engineering, DevOps, automation ...

Minimum Qualifications 5+ years of experience in software engineering, solution design, or architecture roles Strong stakeholder management experience across business and technology domains Strong analytical and problem-solving capabilities Experience working in Agile organizations Bachelor's degree in Computer Engineering, Software Engineering, or a related discipline Fluent English communication … messaging technologies SQL and NoSQL databases Containerization (Docker) Kubernetes CI/CD pipelines Git-based development workflows Good understanding of: Distributed systems System integration API design Scalability patterns Roles and Responsibilities Backend Engineering Design and develop enterprise-grade Back End services using Java. Build APIs and microservices ...

teams, you will help shape the future integration strategy while ensuring high-quality, scalable, and maintainable solutions are delivered across the programme. Key Responsibilities Design and deliver integration solutions, migrating services from legacy platforms to modern strategic integration platforms. Define API specifications and integration patterns, including the transformation … legacy SOAP services into modern RESTful APIs. Apply API-first and domain-driven integration approaches to support reuse, resilience, and long-term maintainability. Contribute to end-to-end solution design, ensuring alignment with wider enterprise architecture principles and transformation objectives. Promote modern engineering practices including automated testing ...

consumers, topics, partitions and consumer groups Cloud: AWS application deployment and support DevOps: CI/CD pipeline implementation and automation Containers: Docker APIs: RESTful API design and development using C# with Open API standard Source Control: GitHub and Azure DevOps Production Engineering: Troubleshooting, monitoring, logging and performance … optimization Highly Desirable Amazon MSK or managed Kafka experience AWS EKS/ECS Terraform/AWS CloudFormation AWS Lambda, API Gateway, SQS, SNS and EventBridge Redis and distributed caching CloudWatch, ELK/OpenSearch, Datadog, Prometheus, Grafana or Splunk OAuth 2.0/JWT and API security AWS certification Experience ...

consumers, topics, partitions and consumer groups Cloud: AWS application deployment and support DevOps: CI/CD pipeline implementation and automation Containers: Docker APIs: RESTful API design and development using C# with Open API standard Source Control: GitHub and Azure DevOps Production Engineering: Troubleshooting, monitoring, logging and performance … optimization Highly Desirable Amazon MSK or managed Kafka experience AWS EKS/ECS Terraform/AWS CloudFormation AWS Lambda, API Gateway, SQS, SNS and EventBridge Redis and distributed caching CloudWatch, ELK/OpenSearch, Datadog, Prometheus, Grafana or Splunk OAuth 2.0/JWT and API security AWS certification Experience ...

Ireland providing specialist services to a wide range of blue-chip clients. The role We are seeking technical polyglots who enjoy both technical architectural design, hands-on coding and peer reviews, though also like the idea of the equally important social/client-facing aspect of the role. … development architecture as well as supporting business analysts and product owners in planning and story-mapping for new development. You will act as technical design authority (TDA) for delivery of technical stories and produce technical documentation artefacts to support the delivery process. Main Responsibilities Duties will include: The design ...

Senior .Net Developer, C#/VB.Net, API, SQL, NW London to £85K A Back End Developer is required to join this established financial software house based in North London. They work with some of the leading brands in retail and media, offering financial management systems developed in house … required with expertise in Visual Basic .NET, C#, SQL Server, and SAP Business One integration. The ideal candidate should have strong skills in RESTful API development, database optimization, and Azure DevOps pipeline management. Knowledge of API security, CI/CD automation, and Swagger documentation is recommended. Responsibilities API ...

SPONSORED Location: London Our client is looking for an experienced Java Developer with active SC clearance . You'll join their team to design, build and maintain RESTful and SOAP microservices using Spring Boot in an Agile environment. As a Java Developer, you will be responsible for designing, developing … preferably should have SC/DV clearance or must be eligible and willing to go through SC/DV clearance. What you'll do Design, develop and deploy RESTful and SOAP microservices using Spring Boot Work with cross-functional teams to analyse requirements and deliver features Write clean, well ...

just familiarity, but production ownership. Azure Integration: Proven experience building applications that consume Azure-native services, including Azure Key Vault for secrets, Azure Storage API, and Azure Service Bus for event-driven messaging. DevOps Mindset: Solid understanding of the full CI/CD lifecycle; comfortable reading and contributing … Dockerfiles and GitHub Actions YAML workflows - not as a DevOps engineer, but as a developer who understands the pipeline their code flows through. API Mastery: Deep expertise in RESTful API design principles, OAuth2 authentication flows (including FusionAuth integration), and DMARC-compliant transactional email logic via SendGrid. Duties ...

workflows at scale. This role emphasizes engineering excellence, operational readiness, and secure, compliant delivery in a fast-paced global environment. Job Responsibilities Lead the design and delivery of user interface capabilities across Execute, from discovery to production support Set front-end technical direction, including architecture, standards, performance, and testing … time or data-intensive user experiences Demonstrated technical leadership in setting standards, leading designs, and mentoring teams Solid software engineering fundamentals, including OO/design patterns, debugging, and documentation Familiarity with agentic development approaches across the software development lifecycle Strong communication skills and ability to work effectively in global ...

Clearance to join a team developing secure, high-volume and highly available backend services and APIs supporting fraud detection and data integrity. Responsibilities: * Design and develop scalable, secure and low-latency backend services. * Develop clean, testable Scala code and REST APIs. * Work with databases and AWS services. * Improve … Support production services and contribute to incident resolution. * Work within an Agile & Continuous Integration. Skills and Experience: * Scala * Play Framework or MVC/REST API frameworks * SQL/Databases * AWS * Continuous Integration * Agile methodologies * API design and development * Testing and automation * Production support/SRE awareness ...

Java and Spring Boot Deploy and support services on AWS (e.g. ECS/EKS, Lambda, RDS, DynamoDB, SQS/SNS) Own services from design through to production support Maintain CI/CD pipelines and infrastructure as code (Terraform, CloudFormation or CDK) Review code and contribute to architecture decisions Essential … skills: Commercial experience with Java 21 and Spring Boot Building and running applications on AWS Microservices and API design Reasonable Adjustments: Respect and equality are core values to us. We are proud of the diverse and inclusive community we have built, and we welcome applications from people ...

technical leadership across the Front Office application portfolio, ensuring solutions are aligned with business strategy, architectural standards, and operational requirements Lead the design, development, implementation, and support of technology solutions that enable investment, trading, portfolio management, and related business capabilities Partner with Product Owners, business stakeholders, architects, and engineering … platform simplification, application resiliency, automation, and AI-enabled capabilities Act as the primary technical authority for the application suite, making informed decisions on architecture, design patterns, technology selection, and engineering best practices Manage technical deliveries across multiple concurrent initiatives, ensuring successful execution, risk management, stakeholder communication, and high-quality ...

technical leadership across the Front Office application portfolio, ensuring solutions are aligned with business strategy, architectural standards, and operational requirements Lead the design, development, implementation, and support of technology solutions that enable investment, trading, portfolio management, and related business capabilities Partner with Product Owners, business stakeholders, architects, and engineering … platform simplification, application resiliency, automation, and AI-enabled capabilities Act as the primary technical authority for the application suite, making informed decisions on architecture, design patterns, technology selection, and engineering best practices Manage technical deliveries across multiple concurrent initiatives, ensuring successful execution, risk management, stakeholder communication, and high-quality ...

technical leadership across the Front Office application portfolio, ensuring solutions are aligned with business strategy, architectural standards, and operational requirements Lead the design, development, implementation, and support of technology solutions that enable investment, trading, portfolio management, and related business capabilities Partner with Product Owners, business stakeholders, architects, and engineering … platform simplification, application resiliency, automation, and AI-enabled capabilities Act as the primary technical authority for the application suite, making informed decisions on architecture, design patterns, technology selection, and engineering best practices Manage technical deliveries across multiple concurrent initiatives, ensuring successful execution, risk management, stakeholder communication, and high-quality ...

following key skills: - At least three years commercial scala programming - Strong framework experience (Akka, Play etc) - Relational database experience - PostgreSQL - MongoDB, NoSQL - RESTful API design and integration experience - Solid unit test understanding - Spec2, scalaTest etc - Experience working in a TDD/BDD driven environment - Containerization experience - Docker, Kubernetes … well-established friendly team then please apply now to be considered and for further details. Scala Developer Up to £85,000 Scala, REST Api, NoSQL, TDD/BDD, functional programming, CI/CD, Play, Akka ...

following key skills: - At least three years commercial scala programming - Strong framework experience (Akka, Play etc) - Relational database experience - PostgreSQL - MongoDB, NoSQL - RESTful API design and integration experience - Solid unit test understanding - Spec2, scalaTest etc - Experience working in a TDD/BDD driven environment - Containerization experience - Docker, Kubernetes … well-established friendly team then please apply now to be considered and for further details. Scala Developer Up to £85,000 Scala, REST Api, NoSQL, TDD/BDD, functional programming, CI/CD, Play, Akka ...

Cloud and Order Management capabilities to support our clients retail and service operations. You will define technical standards, ensure best practices, and guide the design of integrated solutions that enhance customer experience and operational efficiency. Success in this role means delivering secure, scalable, and high-performing platforms that enable … solutions, ensuring alignment with enterprise standards. Collaborating with business and technical teams to translate requirements into scalable, secure, and high-performing solutions. Leading technical design sessions and providing guidance to development teams on best practices and integration patterns. Defining and maintaining architectural documentation, including data models, integration diagrams ...

core business systems. This is a hands-on development role working closely with other Developers, Business Analysts, Testers and Product Owners to design, build and support high-quality, maintainable software. In particular: Designing and developing robust Modern .Net (C#) and Angular solutions that support critical business processes Building well … knowing how to manage those risks. SKILLS REQUIRED You will be comfortable working in a collaborative development team, understanding business requirements, contributing to technical design decisions and delivering well-structured code that is reliable, maintainable and easy to support. You will be able to demonstrate: Strong commercial experience with ...

heavily backend-biased position but given the size of the team you will be working across the stack when needed Build scalable, performant systems Design and deliver end-to-end features with direct impact on customer value Work with product and ML teams to help translate abstract and complex … software function About you: Strong ability across scalable and performant systems You have a product mindset Statically typed language expertise Experience with API design Low ego and love of engineering Full details are available. Please don't hesitate to reach out for more information. ...

teams, mentor senior engineers, and drive step-change impact across business-critical, scientific, and R&D domains. Key Responsibilities Provide technical leadership in the design and architecture of large-scale, production-grade ML systems and platforms across the organisation. Own end-to-end delivery of complex ML solutions from … scientific problem framing and algorithm design through to deployment, operationalisation, and product delivery. Apply advanced machine learning science to develop novel algorithms and models, ensuring they are rigorously validated and deployed as scalable, reliable, production-grade products. Bridge the gap between scientific research and enterprise deployment taking ML innovations ...