26 to 42 of 42 API Design Jobs in London

Manchester) Up to £160,000 + benefits/Bonus Join a leading financial technology and trading organisation driving innovation in electronic markets. As an eFX Software Engineer, you'll design and deliver high-performance, low-latency trading solutions that underpin mission-critical systems. This role offers the chance to work on cutting-edge technology where speed, scalability, and resilience … are key. About the Role Lead the design and development of secure, high-performance eFX systems Define and evolve Java patterns and techniques optimised for ultra-low latency (<40s) Architect fault-tolerant, scalable trading systems Influence technical strategy, architecture, and product roadmaps Collaborate with multiple teams to deliver best-in-class E-trading platforms Ensure all solutions meet security … compliance, and performance standards What You'll Bring Strong experience in software engineering, architecture, and database design Expert-level Java development, including low-GC and lock-free patterns Proven background in FX trading systems, pricing, and risk management Deep understanding of CPU architecture, cache optimisation, and Linux performance tuning Expertise in networking and messaging (TCP, UDP, Multicast, FIX) Knowledge More ❯

Manchester)Up to £160,000 + benefits/Bonus Join a leading financial technology and trading organisation driving innovation in electronic markets. As an eFX Software Engineer, you'll design and deliver high-performance, low-latency trading solutions that underpin mission-critical systems. This role offers the chance to work on cutting-edge technology where speed, scalability, and resilience … are key. About the Role Lead the design and development of secure, high-performance eFX systems Define and evolve Java patterns and techniques optimised for ultra-low latency (<40μs) Architect fault-tolerant, scalable trading systems Influence technical strategy, architecture, and product roadmaps Collaborate with multiple teams to deliver best-in-class E-trading platforms Ensure all solutions meet security … compliance, and performance standards What You'll Bring Strong experience in software engineering, architecture, and database design Expert-level Java development, including low-GC and lock-free patterns Proven background in FX trading systems, pricing, and risk management Deep understanding of CPU architecture, cache optimisation, and Linux performance tuning Expertise in networking and messaging (TCP, UDP, Multicast, FIX) Knowledge More ❯

this is the opportunity for you What you'll be doing As a Technical Writer, you will: Enable creation and maintenance of an extensive range of technical documentation, including API guides, integration manuals, SDK documentation, tutorials, and partner onboarding materials Collaborate with product managers, internal & external engineers, and partners to identify documentation requirements and inform API design … progress to ensure timely publication Advocate for user, partner, and external developer needs and incorporate feedback to enhance documentation quality and developer experience Guide our internal engineers as they design, build, document and expose APIs What you bring You'll thrive in this role if you have: A strong understanding of engineering concepts related to APIs , including authentication methods … OAuth, API keys) and webhooks Autonomy and Proactivity to set your own roadmap, prioritise tasks, and proactively identify documentation gaps Great communication skills for creating and maintaining clear, user friendly documentation and ensuring content quality and consistency Experience in championing the developer experience by partnering with designers to improve information architecture, content discoverability, and overall usability Analytical skills to More ❯

data-heavy workloads while influencing product strategy. Requirements: Strong foundations in algorithms, data structures, and distributed systems Experience building and operating large-scale backend systems Expertise in system and API design, scalability, and performance tuning Proficiency in a modern backend language (Java preferred) Knowledge of cloud-native architectures, containers, and CI/CD Proven leadership in technical strategy More ❯

and data-heavy workloads while influencing product strategy.Requirements: Strong foundations in algorithms, data structures, and distributed systems Experience building and operating large-scale backend systems Expertise in system and API design, scalability, and performance tuning Proficiency in a modern backend language (Java preferred) Knowledge of cloud-native architectures, containers, and CI/CD Proven leadership in technical strategy More ❯

testing activities. Key Responsibilities: Lead requirements analysis and documentation for complex digital projects. Write clear, detailed user stories for development and test teams. Specify and model data requirements, including API documentation. Facilitate workshops with stakeholders to capture business needs. Collaborate with Agile teams to ensure alignment with delivery goals. Maintain awareness of emerging technologies, including generative AI. Essential Skills … modelling. Demonstrated ability to write user stories for large development teams. Experience working in high-performing Agile or Scrum environments. Desirable Skills: Knowledge of digital transformation programmes. Familiarity with API design and documentation. Awareness of generative AI concepts. Professional certifications (e.g., BCS, IIBA) desirable but not mandatory. Please submit a copy of your CV for more information on More ❯

Linux tuning, performance profiling Background in designing high-performance architectures and distributed systems Strong grasp of FX pricing, risk, and trading workflows Solid engineering fundamentals: testing, CI/CD, API design, automation Why join? Work on mission-critical systems powering global trading Highly technical culture with genuine ownership and impact Flexibility in working hours and hybrid setup More ❯

their potential applications. Develop clear and effective data models and supporting documentation. Write and maintain user stories for large development and testing teams. Define and document data requirements and API specifications . Collaborate closely with cross-functional teams in an Agile/Scrum environment to ensure successful delivery. Essential Skills & Experience Strong core business analysis capabilities, including requirements definition … and stakeholder management. Demonstrated experience in data modelling , API documentation , and digital service delivery . Proven success working within Agile/Scrum frameworks and contributing to high-performing agile teams . Proficiency with Jira and other agile delivery tools. Prior experience working within the public sector (central or local government). Solid understanding of digital delivery practices in government … or similar settings. Desirable Knowledge Awareness of Generative AI tools and their potential applications. Experience defining and managing data requirements across large-scale systems. Familiarity with API design and documentation standards. If you're an experienced Business Analyst looking to make an impact within a digital transformation environment, we'd love to hear from you. More ❯

full stack engineer in London. Tasks Ship polished, accessible UIs in React 18 + TypeScript with Tailwind and Radix UI/shadcn. Own end-to-end feature delivery: discovery → design collaboration → implementation → release. Model complex client state with MobX/MobX State Tree and drive migrations where needed. Integrate APIs and third-party services using React Query, Axios, and … server-side TS utilities. Build reusable component patterns and enforce design-system consistency and a11y. Keep things fast: performance profiling, bundle budgets, and Vite build pipeline improvements. Raise the quality bar with tests (Vitest, Playwright/Cypress/Jest), code reviews, and observability. Improve DX: ESLint/Prettier configs, CI feedback loops, Storybook-style workflows. Requirements 2+ years building … web apps with React + TypeScript. Proven track record shipping complex UI flows with modern component libraries (Radix UI, shadcn/ui, or similar). Comfortable across the stack: API design, data contracts, and backend collaboration. Real-world state management experience (MobX, Redux, Zustand, etc.), including async workflows. Strong testing discipline (unit, integration, E2E) and solid Git-based More ❯

Have deep familiarity with Python data ecosystem Understanding of Jupyter notebooks Exposure to machine learning libraries like PyTorch, XGBoost and JAX Understanding of crypto or traditional financial markets Strong API design and documentation skills What do you get in return? Up to 250k base (depending on experience) 3 days in their new central London office Pension scheme More ❯

Have deep familiarity with Python data ecosystem Understanding of Jupyter notebooks Exposure to machine learning libraries like PyTorch, XGBoost and JAX Understanding of crypto or traditional financial markets Strong API design and documentation skills What do you get in return? Up to £250k base (depending on experience) 3 days in their new central London office Pension scheme More ❯

fast-moving environment. Your Skills and Experience 6+ years of experience in backend systems, with 1–3 years in engineering management or strong technical leadership roles Proven ability to design, build, and scale platform systems, owning complex projects from architecture to production Strong experience with cloud-based distributed systems, including architectural decision-making, deployment strategies, and operational excellence Advanced … backend development skills with an emphasis on API design, scalability, observability, and monitoring Experience mentoring engineers and promoting high technical standards within fast-growing teams Excellent communication skills with the ability to collaborate across engineering, product, and cross-functional groups Interest in, or exposure to, ML model serving, GPU-based infrastructure, or ML platform tooling (preferred but not More ❯

Solution Architect - Client-facing TypeScript API Design Hybrid (2 Days Onsite in Central London) £105,000-£110,000 + 15% Discretionary Bonus Method Resourcing is thrilled to be partnering with a global leader in the travel industry who are hiring a Client-facing Solution Architect to join a high-performing architectural team click apply for full job details More ❯

Stack Software Engineer to join a leading global investment management firm in London. Paying up to 120k plus bonus per annum, you will contribute to the development, optimisation, and design of front-office applications, collaborating with portfolio managers and product owners to create innovative and high-performance solutions. As a Senior Full Stack Software Engineer, you will play a … React) with a focus on UI/UX. Proven backend expertise, particularly with Java (Python, Node.js a plus), and experience building distributed microservices-based architectures. Strong knowledge of system design principles, scalable architecture patterns, and API design. Hands-on experience with relational (Postgres, MySQL) and NoSQL (DynamoDB) databases. Proficiency in cloud platforms (AWS, Azure, or GCP). Experience More ❯

Mercor is hiring on behalf of a leading AI lab for an experienced Backend & DevOps Engineer to design, build, and scale microservices-based infrastructure that powers next-generation AI systems. You'll own both core backend services and infrastructure automation, ensuring distributed systems are fast, reliable, and secure. This position blends software engineering, DevOps, and system design, working … and reliability. Continuously improve automation, deployment speed, and operational efficiency. Requirements 3+ years of experience in backend engineering and/or DevOps roles. Strong understanding of microservices architecture and API design. Proficiency in Go, Python, , or Java. Hands-on experience with Docker, Kubernetes, and cloud environments (AWS/GCP). Familiarity with Terraform, Helm, ArgoCD, or GitHub Actions. Experience More ❯

and validation processes. Identify and mitigate risks associated with migration and system cutover. Core Skills & Experience: Proven expertise in PAS systems and complex data migration projects. Strong knowledge of API design and integration . Advanced data modelling skills for structured and semi-structured data. Proficiency in XML, JSON, and Excel for data handling and transformation. Ability to work More ❯

Technical Business Analyst - London/Remote (Technical Business Analyst, Technical BA, Business Analyst, BA, Technical Analyst, Systems Analyst, Solutions Architect, API Designers, Systems Analysts, RESTful APIs, Web APIs, JIRA, Confluence, user stories, JSON, Open API Specification, Swagger, HTTP, Agile, SQL) Our client is an exciting and cutting-edge fintech giant with a global presence. They have been a … their worldwide client base has never been stronger, with significant growth in the last 12 months. They are looking for a Technical Business Analyst with a background designing RESTful API services in fast-paced development teams, to work on consulting projects and help to align information technology with business operations and processes. We are seeking an Technical Business Analyst … Restful APIs, data models and event-driven processes for development teams. You will also need to be comfortable in HTTP, JIRA/Confluence, user stories, JSON Schema and Open API Specification (Swagger). Excellent Agile and SQL is expected, as is experience in Postman, BPMN and Gherkin. Exceptional communication and interpersonal skills are a must, as is the ability More ❯