9 of 9 Contract API Design Jobs in London

Senior API Technical Consultant (GraphQL Specialist) Design and build next generation of high-scale SaaS platforms. We're looking for a senior/lead engineering consultant with deep expertise in GraphQL to take a leading role in developing our robust TypeScript/Node.js backend. 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 Deliverables Design and build sophisticated, scalable GraphQL APIs and backend services using TypeScript and Node.js. Lead the design and evolution of our API schemas, ensuring they meet the complex demands of a rapidly growing platform. Champion best … team to guide process improvements and make key architectural decisions. Experience Extensive production experience architecting and delivering complex applications with TypeScript and Node.js . Expert level GraphQL , including advanced API design, schema evolution, performance optimisation. Strong automated testing frameworks like Vitest and Playwright . Proficiency with modern DevOps tooling and cloud-native architecture, including Docker , Helm , Kubernetes . More ❯

software across the full stack, from front-end UI to back-end APIs Build and maintain performant applications using React, Next.js, and Node.js Contribute to architectural discussions and technical design decisions Collaborate with product, design, and platform teams to align on feature delivery Write clean, maintainable code and participate in peer code reviews Optimise applications for performance, scalability … stack development using React , Next.js , and JavaScript/TypeScript Proven backend engineering skills using Node.js and/or modern languages like Python , Ruby , Scala , or Rust Solid understanding of API design and integration Track record of delivering end-to-end web applications Knowledge of performance tuning and front-end optimisation Comfortable in Agile environments with CI/CD More ❯

a Senior Java Developer, you will play a key role in designing, developing, and maintaining enterprise-grade applications, while mentoring junior engineers and helping shape technical strategy. Key Responsibilities Design, develop, and maintain Java-based applications and services . Write clean, efficient, and well-documented code . Participate in code reviews and provide constructive feedback. Collaborate with cross-functional … teams to define, design, and deliver new features . Troubleshoot and debug complex issues. Required Qualifications Professional Java software development experience. Strong understanding of object-oriented programming and design patterns . Hands-on experience with Spring and Hibernate frameworks. Solid experience with relational databases (MSSQL, Oracle). Proven experience with RESTful API design and development . More ❯

systems/subsystems and their interfaces while defining non-functional requirements. Collaborate with stakeholders and vendors to ensure solutions are fit for purpose and evaluate the impact of strategic design decisions. Lead the rapid shaping of high-level architecture while maintaining flexibility and modularity. Utilize best practices and templates to create comprehensive architectural designs. Work closely with Product Managers … to prioritize technology-focused backlog items. Clarify architecture for development teams and provide solution options for any challenges. Conduct design reviews to ensure all non-functional requirements are met, focusing on aspects such as security, performance, and scalability. What We're Looking For: To thrive in this role, you should have: Must Have - Domain knowledge in Corporate Payments and … familiarity with related areas such as Accounting Services and Liquidity Management. Proficiency in API Design, microservices, and integration platforms. Experience with Cloud Platforms (AWS, Azure, GCP). Knowledge of DevOps, CI/CD pipelines, and containerization (Docker, Kubernetes). A strong foundation in both Waterfall and Agile SDLC methodologies. Excellent coordination and communication skills to engage with business More ❯

systems/subsystems and their interfaces while defining non-functional requirements. Collaborate with stakeholders and vendors to ensure solutions are fit for purpose and evaluate the impact of strategic design decisions. Lead the rapid shaping of high-level architecture while maintaining flexibility and modularity. Utilize best practices and templates to create comprehensive architectural designs. Work closely with Product Managers … to prioritize technology-focused backlog items. Clarify architecture for development teams and provide solution options for any challenges. Conduct design reviews to ensure all non-functional requirements are met, focusing on aspects such as security, performance, and scalability. What We're Looking For:To thrive in this role, you should have: Must Have - Domain knowledge in Corporate Payments and … familiarity with related areas such as Accounting Services and Liquidity Management. Proficiency in API Design, microservices, and integration platforms. Experience with Cloud Platforms (AWS, Azure, GCP). Knowledge of DevOps, CI/CD pipelines, and containerization (Docker, Kubernetes). A strong foundation in both Waterfall and Agile SDLC methodologies. Excellent coordination and communication skills to engage with business More ❯

adapt to evolving requirements Collaborate with stakeholders, vendors, and development teams Ensure non-functional requirements are met (e.g. security, scalability, performance) Support agile delivery and architectural runway planning Lead design reviews and resolve technical impediments Required Skills: Deep domain expertise in Corporate Payments (essential) and related financial services Strong experience in API design , microservices , and integration platforms More ❯

adapt to evolving requirements Collaborate with stakeholders, vendors, and development teams Ensure non-functional requirements are met (e.g. security, scalability, performance) Support agile delivery and architectural runway planning Lead design reviews and resolve technical impediments Required Skills: Deep domain expertise in Corporate Payments (essential) and related financial services Strong experience in API design , microservices , and integration platforms More ❯

in a greenfield, lab-first environment to prototype, iterate, and deploy solutions that meet the highest standards of performance, security, and compliance in a regulated financial setting. Accountabilities & Responsibilities Design and develop modern, responsive front-end applications from the ground up using React, TypeScript, and Next.js. Build secure, performant user interfaces that integrate with LLM APIs (e.g., Gemini, Azure … systems. Implement advanced front-end security features including token handling, session management, data masking, and audit logging. Translate UX/UI designs into modular, reusable components aligned with enterprise design systems. Integrate front-end applications with REST/GraphQL APIs, WebSockets, and backend services. Collaborate with AI engineers, backend developers, and cloud architects to deliver end-to-end solutions. … regular code reviews. Deploy applications to GCP (Firebase, Cloud Run) and Azure App Services using CI/CD pipelines hardened for security and compliance. Participate in code reviews, technical design discussions, and architecture planning sessions. Required Knowledge, Skills & Experience Proven experience building secure, production-grade front-end applications in regulated environments (e.g., finance, healthcare, government). Strong proficiency in More ❯

Experience working closely with product teams and designing for real users Strong frontend skills (JavaScript/Typescript, React/Angular, HTML) and backend expertise (Node.js, Python) Proven experience in API design and system integration Proficiency with Microsoft Azure and familiarity with databases, IAM, containers, and deployment tools Comfortable with rapid prototyping tools (e.g., Figma) Solid understanding of the … platforms Support low-code solutions, especially within Power Platform Agile & Iterative Development Work within a modern agile framework Participate in backlog grooming, technical scoping, and story writing Engage in design sessions, code reviews, and retrospectives Security, Quality & Operations Ensure compliance with security, privacy, and operational standards Monitor and improve the health of production code Enhance testing and deployment pipelines More ❯