14 of 14 Contract API Design Jobs in the UK

Solutions Architect – SC Cleared – Bristol – Contract Our client is looking to recruit an experienced Leader and Design Authority to fulfil the System Design Authority (SDA) role for a key Project. The Solutions Architect should bring leadership and governance to support the solution's development and ensure the design aligns with the strategic vision. The Solutions Architect will … in the disciplines involved in full lifecycle software and systems Engineering. In particular, you should have good experience in systems integration, with a strong emphasis on software-led integration, API design and implementation, and secure interoperability, alongside basic networking skills. What you will do: The Solutions Architect will be responsible for the end-to-end design and … implementation of a key software system. This will include analysis and design, assisting with and governing software development and hosting, and achieving successful IT health checks, testing, and deployment. About You: As an experienced Solutions Architect, you will have an outstanding range of knowledge and experience in integrating systems containing electronic, electrical, and mechanical components and sub-systems. Specific More ❯

Halian Technology are searching for an Interim API Integrations Specialist to join our client's forward-thinking technology team. Our client is a dynamic and rapidly growing energy supplier based in Oxfordshire, committed to driving business success through smart, reliable energy solutions. Our client challenges the existing marketplace with a tech-driven, customer-focused approach and foster a culture … designing cutting-edge integrations, delivering high-quality solutions, and want to work in a company where your expertise is valued and supportedthis is the role for you. Key Responsibilities: Design, develop, and maintain API integrations between internal systems and external SaaS platforms. Collaborate with product, data, and engineering teams to identify integration requirements and deliver robust solutions. Monitor … and troubleshoot integration workflows, ensuring data consistency across platforms. Translate business requirements into technical specifications for system connectivity. Build and maintain API documentation, providing guidance on integration best practices. Ensure all integrations meet compliance, security, and performance standards. Work closely with SaaS vendors and partners to coordinate technical efforts. Key Requirements: Essential: Strong expertise in digital engineering, CMS design More ❯

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 ❯

transformation programme, and are looking for an experienced Integration Architect to join on a 12-month contract . This role is ideal for someone who specialises in system integration, API design, and cloud-based architecture (Azure) and enjoys shaping strategy as well as guiding delivery teams. Key Responsibilities Define and deliver the integration architecture strategy for a group … wide transformation. Design and govern API-led integrations, interface specifications, message schemas, and data flows. Work closely with Solution Architects, Cloud Architects, Product Owners and delivery teams to ensure scalable, secure and future-proof integration solutions. Champion integration best practices, standardisation and reusability across programmes. Provide technical leadership, documentation, and mentorship to delivery teams. Ensure all integration solutions … data protection standards. What We're Looking For Proven experience as an Integration Architect/Solution Architect with strong integration focus Hands-on knowledge of Microsoft Azure integration services (API Management, Service Bus, Logic Apps, Event Grid, etc.) Strong understanding of enterprise integration patterns, API management platforms (Apigee/Azure API Mgmt) Experience working in agile delivery More ❯

from home Role Overview A key client of ours in the media space are seeking an experienced Senior Full Stack Web Developer to play a key role in the design, development, and delivery of innovative, high-performance web applications. This position is central to the ongoing evolution of our programmatic and data-driven integration platforms, with a focus on … across multiple environments. This is an opportunity to work in a collaborative, fast-moving environment where technical expertise, creative problem-solving, and continuous improvement are highly valued. Key Accountabilities Design, develop, and maintain scalable and secure software applications aligned with architectural and business objectives. Partner with business, technical, and product leaders to deliver solutions that support the company's … strategic vision. Champion best practices in coding standards, testing, deployment, and DevOps automation. Contribute to a culture of innovation, collaboration, and continuous technical improvement. Key Responsibilities Lead the design and development of dynamic, responsive web applications using React.js , Node.js , and related technologies. Build and optimize PostgreSQL databases, including schema design, complex queries, and performance tuning. Implement and manage More ❯

every year of education • At least 8-10 years of experience with Information Technology Key Responsibilities • Develop and maintain enterprise-scale .NET applications using ASP.NET Core 9.0 and C# • Design and implement RESTful APIs for biogas trading, inventory management, and regulatory reporting • Build complex business logic for RINS credit calculations, LCFS compliance, and carbon credit trading • Work with PostgreSQL … and Microsoft Identity Platform • Develop email workflow systems and automated reporting for regulatory compliance • Create scheduled background jobs using Quartz.NET for data processing and calculations • Integrate with Microsoft Graph API for SharePoint document management via Azure MS Graph • Build real-time features using SignalR for live trading updates • Implement data validation using FluentValidation • Work with Docker and OpenShift for … containerized deployments Required Technical Skills • 5+ years of experience with .NET development (C#, ASP.NET Core) • Strong experience with Entity Framework Core and PostgreSQL • Proficiency in RESTful API design and OpenAPI/Swagger documentation • Experience with authentication systems (OAuth2, JWT, Azure AD) • Knowledge of containerization (Docker) and Kubernetes/OpenShift • Experience with background job processing and scheduled tasks • Understanding More ❯

and Spring Boot experience, solid understanding of Kubernetes and AWS services, and hands-on database development with SQL-based systems. Familiarity with mobile integrations (iOS/Android native), RESTful API design, and Agile delivery methodologies will be highly beneficial. This is an exciting opportunity to work in a dynamic FinTech environment where innovation, quality, and performance are at More ❯

ll bring: Proven experience in software integration, with skills in Python, C, Powershell, and CI/CD pipelines Strong knowledge of architectural patterns such as SOA, Microservices, ESB, and API design Expertise in designing and implementing integration solutions for COTS and custom software Familiarity with containerisation (Docker), orchestration (Kubernetes), and virtualisation (VMware, IaaS tools like Ansible, Terraform) Excellent More ❯

backend expertise with Kotlin and Spring Boot (ESSENTIAL) Skilled in designing and maintaining microservices architectures . Confident working with SQL databases (PostgreSQL, MySQL or equivalent). Understanding of RESTful API design and third-party integrations. Experience with testing frameworks , debugging, and performance optimisation. Familiarity with AWS, Docker/Kubernetes and CI/CD pipelines (desirable) Key Responsibilities: Develop … and microservices . Build and optimise SQL schemas and queries for performance and scalability. Integrate APIs and third-party services into core systems. Collaborate with cross-functional teams to design scalable, maintainable software solutions . Participate in code reviews , contributing to team standards and documentation. Support production deployments, monitoring, and issue resolution. Continuously improve application performance, reliability, and user More ❯

Stack or Backend Developer to play a key role in shaping the backend of our next-generation B2C platform. You’ll work closely with our front-end team to design and deliver robust, scalable APIs and infrastructure that power our consumer experience. What You’ll Do: Develop and maintain production-grade APIs and backend systems using Node.js. Leverage AI … and security for scale. Collaborate with front-end engineers to integrate APIs seamlessly. What We’re Looking For: Extensive experience building high-traffic consumer applications. Strong understanding of RESTful API design, database optimization, and security. Proven AI-assisted development workflow. Ability to work autonomously within established technical frameworks. Nice to Have: React/Next.js, Azure, Payload CMS, microservices More ❯

ASAP What we're looking for: 4+ years' experience in software engineering (SaaS or start-up background preferred) Strong proficiency in Python and C#, with hands-on experience in API design and cloud architecture (Azure). Experience with Excel add-ins or Office JavaScript APIs is highly desirable. Exposure to vectorization, RAG (Retrieval-Augmented Generation), or AI-driven … Background or interest in commercial real estate technology. Self-starter with excellent communication skills and the ability to operate autonomously in a dynamic, growing business. What you'll do: Design & Develop: Build and maintain robust back-end services and APIs powering the company's automation suite. Integrate Smartly: Enhance and expand integrations across Microsoft 365 applications (Excel, Word, PowerPoint … . Architect Systems: Help design scalable, secure, and high-performance data infrastructure. Collaborate: Partner closely with the founding team and business stakeholders to translate complex workflows into elegant technical solutions. Lead by Example: Take control of the project, uphold code quality, and drive best practices across the stack. Shape the Future: Contribute to the long-term technical roadmap and More ❯

ASAP What we're looking for: 4+ years' experience in software engineering (SaaS or start-up background preferred) Strong proficiency in Python and C#, with hands-on experience in API design and cloud architecture (Azure). Experience with Excel add-ins or Office JavaScript APIs is highly desirable. Exposure to vectorization, RAG (Retrieval-Augmented Generation), or AI-driven … Background or interest in commercial real estate technology. Self-starter with excellent communication skills and the ability to operate autonomously in a dynamic, growing business. What you'll do: Design & Develop: Build and maintain robust back-end services and APIs powering the company's automation suite. Integrate Smartly: Enhance and expand integrations across Microsoft 365 applications (Excel, Word, PowerPoint … . Architect Systems: Help design scalable, secure, and high-performance data infrastructure. Collaborate: Partner closely with the founding team and business stakeholders to translate complex workflows into elegant technical solutions. Lead by Example: Take control of the project, uphold code quality, and drive best practices across the stack. Shape the Future: Contribute to the long-term technical roadmap and More ❯

This is initially a 6 month contract with the potential to extend and will be a hybrid role that will be based in either London or Coventry . Responsibilities: Design robust integration solutions across commercial, HR, and data platforms within a complex, multi-brand retail environment Lead architectural planning for the decommissioning of legacy systems, ensuring smooth transitions to … modern, scalable services Define and document integration standards, including API strategies, event schemas, and interface contracts to enable decoupled, reusable services Implement event-driven architectures using Kafka to support real-time data exchange and responsive system interactions Collaborate cross-functionally with product managers, engineering teams, and platform leads to define scalable service boundaries and integration touchpoints Support the design … adoption of strategic data services, promoting data integrity, consistency, and standardisation across the enterprise Ensure integration consistency in areas such as data handling, authentication, error management, and versioning Lead design reviews for integration solutions, ensuring alignment with enterprise architecture principles and governance frameworks Act as a trusted advisor, championing best practices in integration architecture and guiding teams on modern More ❯

days in-office per week, occasional on-site workshops Contract: Initial 6-month contract (potential for extension) Overview: We are seeking an experienced Solution Architect to lead the design and delivery of integration solutions within our Asset Management ecosystem. The successful candidate will play a key role in defining target architectures, delivering integration designs, and ensuring seamless interoperability between … technically adept, business-minded professional who can bridge operational and technology teams, deliver robust integration solutions, and communicate effectively with stakeholders across the organization. Key Responsibilities: Lead the Integration Design for a fault reporting solution, including ServiceNow and IBM Maximo integration. Define and document the Target Architecture for the wider Asset Management ecosystem. Collaborate with business, operational, and technical … years’ experience in Solution Architecture , ideally within large, complex corporate environments. Strong understanding of Asset Management Systems and associated data models. Proven experience with ServiceNow platform and integration design . Experience with IBM Maximo (or alternative EAM platforms such as IFS or Ultimo ). Proficiency in data integration , API design , and user interface considerations . Familiarity with More ❯