26 to 50 of 129 API Design Jobs in London

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 ❯

London, Sheffield, and Bristol. Salary: £40k to £80k What You'll Be Doing as a Software Engineer: Lead technical aspects of full stack development projects and mentor junior engineers Design and build scalable web applications using modern frontend and backend technologies Develop responsive user interfaces and robust REST APIs Design and maintain database schemas, queries, and optimise performance … aspects of full stack development projects Strong proficiency in TypeScript/JavaScript and modern frontend frameworks (React, , Svelte, or similar) Backend expertise with Python (Django or FastAPI) and RESTful API design Database proficiency with PostgreSQL including schema design and query optimization Experience with containerisation (Docker) Knowledge of CI/CD pipelines and testing methodologies (unit, integration, automated … testing) Leadership skills for mentoring engineers and communicating with stakeholders Understanding of software design principles and performance optimization techniques Track record of successful project delivery in a technical leadership capacity You may also have some of the desirable skills and experience: Experience with Kubernetes for container orchestration Knowledge of microservices architecture patterns and implementation Familiarity with object storage solutions More ❯

a standard backend role. We are seeking a foundational engineer to own our single greatest strategic asset: our unique, privileged access to network-level intelligence via the GSMA CAMARA API standard. This is our “right to win”, and you will be the engineer responsible for building the bridge to it. You will be the Critical Path Owner for Track … Key Responsibilities Telco Integration & Architecture Own and build the Security Signal Ingestion path, the secure, low-latency, and out-of-band data channel connecting to our founding members' network API gateways. Architect and implement a carrier-agnostic, vendor-agnostic connector layer to consume RESTful APIs from a heterogeneous global landscape of telco partners and IMS vendors (e.g., Nokia, Ericsson … technical liaison to the engineering teams at our telco founders (Deutsche Telekom, Singtel, SKT, etc.), working “hand-in-glove” to navigate, validate, and productionize their new CAMARA network APIs. Design and build the high-throughput microservices that will query, ingest, normalize, and cache network signals (e.g., sim-swap, device-roaming-status) to be used in our real-time Scam More ❯

a standard backend role. We are seeking a foundational engineer to own our single greatest strategic asset: our unique, privileged access to network-level intelligence via the GSMA CAMARA API standard. This is our right to win, and you will be the engineer responsible for building the bridge to it. You will be the Critical Path Owner for Track … Key Responsibilities Telco Integration & Architecture ? Own and build the Security Signal Ingestion path, the secure, low-latency, and out-of-band data channel connecting to our founding members' network API gateways. ? Architect and implement a carrier-agnostic, vendor-agnostic connector layer to consume RESTful APIs from a heterogeneous global landscape of telco partners and IMS vendors (e.g., Nokia, Ericsson … technical liaison to the engineering teams at our telco founders (Deutsche Telekom, Singtel, SKT, etc.), working hand-in-glove to navigate, validate, and productionize their new CAMARA network APIs. ? Design and build the high-throughput microservices that will query, ingest, normalize, and cache network signals (e.g., sim-swap, device-roaming-status) to be used in our real-time Scam More ❯

a standard backend role. We are seeking a foundational engineer to own our single greatest strategic asset: our unique, privileged access to network-level intelligence via the GSMA CAMARA API standard. This is our right to win, and you will be the engineer responsible for building the bridge to it. You will be the Critical Path Owner for Track … Key Responsibilities Telco Integration & Architecture Own and build the Security Signal Ingestion path, the secure, low-latency, and out-of-band data channel connecting to our founding members' network API gateways. Architect and implement a carrier-agnostic, vendor-agnostic connector layer to consume RESTful APIs from a heterogeneous global landscape of telco partners and IMS vendors (e.g., Nokia, Ericsson … technical liaison to the engineering teams at our telco founders (Deutsche Telekom, Singtel, SKT, etc.), working hand-in-glove to navigate, validate, and productionize their new CAMARA network APIs. Design and build the high-throughput microservices that will query, ingest, normalize, and cache network signals (e.g., sim-swap, device-roaming-status) to be used in our real-time Scam More ❯

and automate their Platform as a Service (PaaS) environment. What You’ll Be Doing: Own architecture and technical decisions across squads; accountable for how software is built and shipped. Design and develop distributed, scalable microservices (C# .NET Core or Node.js) and REST/JSON APIs. Build modern React + TypeScript UIs with component-driven design, advanced state management … and reusable frameworks. Leverage AWS services (Lambda, API Gateway, SQS/SNS, Step Functions, S3, IAM) to deliver secure, event-driven systems. Embed testing-first practices (TDD/BDD, contract tests, Jest/RTL, Playwright/Cypress, xUnit/NUnit) to raise code quality. Implement modern CI/CD (GitHub Actions) and Infrastructure as Code (Terraform, CloudFormation, AWS CDK … . Model secure-by-design principles; ensure robust authentication/authorisation (OAuth2, JWT) and data governance. Mentor engineers, set patterns, run PoCs, and unblock complex problems across squads. Champion “Always ship each cycle”; partner with Product to balance scope, delivery, and quality. Drive modernisation: sunset legacy code, reduce tech debt, and improve performance, reliability, and observability. Who We’re More ❯

and automate their Platform as a Service (PaaS) environment. What You’ll Be Doing: Own architecture and technical decisions across squads; accountable for how software is built and shipped. Design and develop distributed, scalable microservices (C# .NET Core or Node.js) and REST/JSON APIs. Build modern React + TypeScript UIs with component-driven design, advanced state management … and reusable frameworks. Leverage AWS services (Lambda, API Gateway, SQS/SNS, Step Functions, S3, IAM) to deliver secure, event-driven systems. Embed testing-first practices (TDD/BDD, contract tests, Jest/RTL, Playwright/Cypress, xUnit/NUnit) to raise code quality. Implement modern CI/CD (GitHub Actions) and Infrastructure as Code (Terraform, CloudFormation, AWS CDK … . Model secure-by-design principles; ensure robust authentication/authorisation (OAuth2, JWT) and data governance. Mentor engineers, set patterns, run PoCs, and unblock complex problems across squads. Champion “Always ship each cycle”; partner with Product to balance scope, delivery, and quality. Drive modernisation: sunset legacy code, reduce tech debt, and improve performance, reliability, and observability. Who We’re More ❯

practice and technology to all areas of our business specifically designed for our global reach. About the Role We're seeking a Principal Full Stack Engineer to lead the design, development, and scaling of AI-powered digital products that serve infrastructure, engineering, and consulting professionals around the globe. This is a hands-on leadership role that blends deep technical … providing technical direction and mentoring a small cross-functional team of engineers and data scientists, helping ensure excellence and strong delivery outcomes. What You'll Do Build scalable products: Design, build and maintain robust, secure full-stack applications that integrate AI/ML models and serve our external clients and internal users across Mott MacDonald at global scale. Lead … including CloudWatch, Sentry, or DataDog, to ensure application stability, performance optimisation, and effective issue resolution Experience managing or mentoring engineering teams, including cross-functional collaboration. Understanding of secure architecture, API design, and performance optimisation. Experience with modern DevOps practices including CI/CD, containerisation (Docker, Kubernetes), and infrastructure as code (Terraform). Why Join Us Build purposeful, high More ❯

evolve and automate their Platform as a Service (PaaS) environment. What Youll Be Doing: Own architecture and technical decisions across squads; accountable for how software is built and shipped. Design and develop distributed, scalable microservices (C# .NET Core or Node.js) and REST/JSON APIs. Build modern React + TypeScript UIs with component-driven design, advanced state management … and reusable frameworks. Leverage AWS services (Lambda, API Gateway, SQS/SNS, Step Functions, S3, IAM) to deliver secure, event-driven systems. Embed testing-first practices (TDD/BDD, contract tests, Jest/RTL, Playwright/Cypress, xUnit/NUnit) to raise code quality. Implement modern CI/CD (GitHub Actions) and Infrastructure as Code (Terraform, CloudFormation, AWS CDK … . Model secure-by-design principles; ensure robust authentication/authorisation (OAuth2, JWT) and data governance. Mentor engineers, set patterns, run PoCs, and unblock complex problems across squads. Champion Always ship each cycle; partner with Product to balance scope, delivery, and quality. Drive modernisation: sunset legacy code, reduce tech debt, and improve performance, reliability, and observability. Who Were Looking More ❯

Fullstack Developer(AI) to help build the next generation of intelligent, personalized financial platforms. This role blends modern front-end engineering with AI-powered workflows, automation, and human-centered design to deliver seamless digital experiences for users across global markets. You'll join a lean, high-impact product and engineering team where autonomy, creativity, and rapid iteration are core … to how we work. We use AI as a force multiplier-amplifying human creativity, streamlining development, and unlocking new possibilities in financial technology. 🔧 Responsibilities Collaborate with design, backend, and data teams to deliver adaptive, scalable web experiences. Optimize personalization and tracking systems while ensuring accessibility, privacy, and security compliance. Scout and implement AI-driven tools to enhance development workflows … content compatible with AI workflows. Break down complex projects into agile deliverables and contribute to technical documentation. 🧠 Requirements Strong front-end engineering skills (React, TypeScript/JavaScript, CSS, responsive design). Experience with AI-enhanced development tools (e.g., AI code assistants, automated testing, intelligent pipelines). Familiarity with headless CMS platforms and web content workflows. Understanding of web analytics More ❯

Solution Architect Permanent role Job Location : London ( Hybrid) Languages: C#, Python, SǪL Tech Stack: Azure GCP, DDD, EDA, Microservices, API Integration, Distributed Systems Architecture Frameworks: TOGAF, Well Architected, CNCF Cloud Platforms: Microsoft Azure, K8s, familiarity with AWS, Google Cloud Platform Must Have : TOGAF certification, Cloud experience (Azure), Terraform, CI/CD (ADO/GHA), API design and … integration Technologies: EDA, Microservices, API Integration, DDD, Distributed Systems Tools: Visio, UML, Ardoc, Enterprise Architect, Terraform, ADO (for CI/CD), Docker, Kubernetes Nice to Have : Financial Industry experience, Kubernetes, Docker, Experience with security and compliance frameworks (ISO27001 More ❯

Full-Stack Development Solid software engineering background with proficiency in Python, JavaScript/TypeScript, Java, or Go Experience with modern frameworks (React, Node.js, Django, FastAPI) Knowledge of microservices architecture, API design (REST, GraphQL) Experience with containerization (Docker, Kubernetes) and cloud-native development patterns DevOps & SRE Practices Experience implementing CI/CD pipelines and DevOps methodologies Knowledge of infrastructure More ❯

Full-Stack Development Solid software engineering background with proficiency in Python, JavaScript/TypeScript, Java, or Go Experience with modern frameworks (React, Node.js, Django, FastAPI) Knowledge of microservices architecture, API design (REST, GraphQL) Experience with containerization (Docker, Kubernetes) and cloud-native development patterns DevOps & SRE Practices Experience implementing CI/CD pipelines and DevOps methodologies Knowledge of infrastructure More ❯

and Carlos Cadenas (Index Ventures, GoCardless, Skyscanner). The Role: Technical Lead We are looking for a Technical Lead to join our high-calibre software engineering team. You will design, build, and maintain the core services and APIs that power our proprietary platform, with opportunities to contribute to both back-end and front-end codebases, and explore AI & LLMs … you will help drive the next evolution of our platform, designing architecture, managing engineers and shaping how we integrate AI and large language models into our products and workflows. Design, implement, and maintain scalable back-end services and APIs (primarily in Go, with Python for scripting and data). Mentor and manage team members and share knowledge across disciplines. … Lead by example, build fast and help shape our technical roadmap. Take full lifecycle ownership of end-to-end delivery — from technical design and implementation through to testing, deployment, and monitoring. Contribute to front-end code (VueJS) as needed, supporting a collaborative, full stack environment. Work with relational databases (Postgres) and NoSQL solutions (e.g., MongoDB, Redis). Participate in More ❯

we scale, we’re looking for talented Java Engineers with strong Spring Boot experience to join our high-impact engineering team. The Role: As a Java Engineer, you’ll design, build, and optimise Microservices that power our AI-enabled security analytics platform. You’ll work closely with data scientists, DevOps engineers, and product teams to deliver secure, scalable, and … high-performance services. What You’ll Do: Develop and maintain Java-based microservices using Spring Boot Build highly available, distributed systems for real-time threat intelligence Collaborate on architecture, API design, and system optimisation Implement secure coding practices and contribute to our cybersecurity standards Work in a cloud-native environment (AWS/GCP/Azure) using CI/… with cross-functional teams to ship reliable, enterprise-grade features What We’re Looking For: Strong commercial experience with Java 11+ Expertise in Spring Boot, Spring Cloud, and RESTful API development Experience building microservices in distributed systems Understanding of cloud platforms (AWS/GCP/Azure) Familiarity with Docker, Kubernetes, or similar container technologies Knowledge of security principles or More ❯

we scale, we’re looking for talented Java Engineers with strong Spring Boot experience to join our high-impact engineering team. The Role: As a Java Engineer, you’ll design, build, and optimise Microservices that power our AI-enabled security analytics platform. You’ll work closely with data scientists, DevOps engineers, and product teams to deliver secure, scalable, and … high-performance services. What You’ll Do: Develop and maintain Java-based microservices using Spring Boot Build highly available, distributed systems for real-time threat intelligence Collaborate on architecture, API design, and system optimisation Implement secure coding practices and contribute to our cybersecurity standards Work in a cloud-native environment (AWS/GCP/Azure) using CI/… with cross-functional teams to ship reliable, enterprise-grade features What We’re Looking For: Strong commercial experience with Java 11+ Expertise in Spring Boot, Spring Cloud, and RESTful API development Experience building microservices in distributed systems Understanding of cloud platforms (AWS/GCP/Azure) Familiarity with Docker, Kubernetes, or similar container technologies Knowledge of security principles or More ❯

generation Unified Client Experience (UCX) frontend that will streamline client journeys across a range of products and services, in both web and mobile domains. It's an opportunity to design, architect and build a modern frontend using latest technologies and best practices to transform our savings and investment platform. The UCX team consolidates the efforts of the whole organisation … scale, regulated environments - ideally in Investment, Asset or Wealth Management. Solid experience in building and deploying frontend applications in React or React Native with hands-on knowledge of secure API design and authentication services. Experience in Java and Spring Boot, or iOS (Swift) or Android (Kotlin) along with exposure to Figma and Vercel is a big plus. Capable More ❯

the go-to technical voice for engineering and delivery, shaping how apps, services, and systems come together. It’s a varied role that mixes hands-on coding with architectural design and technical leadership. You’ll design and build modern environments, integrate multiple SaaS platforms, and help set the standards for how things are done across the organisation. You … cloud architecture • Infrastructure as code using Terraform and CloudFormation • Docker and Kubernetes • Automation and CI/CD pipelines • GitHub and GitHub Actions Software and Frameworks • React, Node, Next.js, Python • API design and integration • RESTful services and automation Data and Platforms • Salesforce • Google Workspace • Atlassian tools such as Jira and Confluence • Databases including DynamoDB, MongoDB, and RDS Security and … best practice You’ll bring a broad technical background, strong problem-solving ability, and the confidence to define the right approach. If you enjoy combining coding, cloud engineering, and design thinking, and want a role with purpose, autonomy, and impact, then this is for you. More ❯

the go-to technical voice for engineering and delivery, shaping how apps, services, and systems come together. It’s a varied role that mixes hands-on coding with architectural design and technical leadership. You’ll design and build modern environments, integrate multiple SaaS platforms, and help set the standards for how things are done across the organisation. You … cloud architecture • Infrastructure as code using Terraform and CloudFormation • Docker and Kubernetes • Automation and CI/CD pipelines • GitHub and GitHub Actions Software and Frameworks • React, Node, Next.js, Python • API design and integration • RESTful services and automation Data and Platforms • Salesforce • Google Workspace • Atlassian tools such as Jira and Confluence • Databases including DynamoDB, MongoDB, and RDS Security and … best practice You’ll bring a broad technical background, strong problem-solving ability, and the confidence to define the right approach. If you enjoy combining coding, cloud engineering, and design thinking, and want a role with purpose, autonomy, and impact, then this is for you. More ❯

practices. This role would suit someone who thrives in a collaborative environment, enjoys solving complex engineering challenges, and has experience working across the full software delivery lifecycle. Key Responsibilities Design, build, and maintain backend services and APIs using Python (Flask) Collaborate with cross-functional teams including cloud engineers and frontend developers Deploy and maintain applications on AWS or Azure … Solid grasp of version control (Git) and modern software delivery practices Desirable Experience in consulting or working with multiple client projects Familiarity with containerisation (Docker, Kubernetes) Understanding of modern API design and microservice architecture More ❯

practices. This role would suit someone who thrives in a collaborative environment, enjoys solving complex engineering challenges, and has experience working across the full software delivery lifecycle. Key Responsibilities Design, build, and maintain backend services and APIs using Python (Flask) Collaborate with cross-functional teams including cloud engineers and frontend developers Deploy and maintain applications on AWS or Azure … Solid grasp of version control (Git) and modern software delivery practices Desirable Experience in consulting or working with multiple client projects Familiarity with containerisation (Docker, Kubernetes) Understanding of modern API design and microservice architecture More ❯

generation Unified Client Experience (UCX) frontend that will streamline client journeys across a range of products and services, in both web and mobile domains. It's an opportunity to design, architect and build a modern frontend using latest technologies and best practices to transform our savings and investment platform. The UCX team consolidates the efforts of the whole organisation … scale, regulated environments - ideally in Investment, Asset or Wealth Management. Solid experience in building and deploying frontend applications in React or React Native with hands-on knowledge of secure API design and authentication services. Experience in Java and Spring Boot, or iOS (Swift) or Android (Kotlin) along with exposure to Figma and Vercel is a big plus. Capable More ❯

work across the entire stack to create robust, performant systems that power intelligent autonomous agents. Key Responsibilities: •⁠ ⁠Develop and maintain full stack applications using modern frameworks (Next.js, React, FastAPI) •⁠ ⁠Design and implement RESTful APIs and backend services •⁠ ⁠Build responsive frontends with TypeScript and modern UI frameworks •⁠ ⁠Write comprehensive tests following TDD principles •⁠ ⁠Manage databases and optimize queries (PostgreSQL, Supabase … Skills: •⁠ ⁠2-3+ years full stack development experience •⁠ ⁠Strong proficiency in Python and FastAPI for backend development •⁠ ⁠Proficiency in JavaScript/TypeScript, React/Next.js for frontend •⁠ ⁠RESTful API design and implementation expertise •⁠ ⁠Test-driven development with pytest and testing frameworks •⁠ ⁠Database design and management (PostgreSQL, SQL) •⁠ ⁠Git version control and modern development workflows Desired Skills More ❯

work across the entire stack to create robust, performant systems that power intelligent autonomous agents. Key Responsibilities: •⁠ ⁠Develop and maintain full stack applications using modern frameworks (Next.js, React, FastAPI) •⁠ ⁠Design and implement RESTful APIs and backend services •⁠ ⁠Build responsive frontends with TypeScript and modern UI frameworks •⁠ ⁠Write comprehensive tests following TDD principles •⁠ ⁠Manage databases and optimize queries (PostgreSQL, Supabase … Skills: •⁠ ⁠2-3+ years full stack development experience •⁠ ⁠Strong proficiency in Python and FastAPI for backend development •⁠ ⁠Proficiency in JavaScript/TypeScript, React/Next.js for frontend •⁠ ⁠RESTful API design and implementation expertise •⁠ ⁠Test-driven development with pytest and testing frameworks •⁠ ⁠Database design and management (PostgreSQL, SQL) •⁠ ⁠Git version control and modern development workflows Desired Skills More ❯

practices (code quality, CI/CD, security etc). Working within a project management/agile delivery methodology Experience in technical ownership for a product or software solution, covering design, estimation, shaping and user story/requirement creation Documentation of solutions (e.g. architecture, configuration, release, support-handover Collaborate and liaise with other Version 1 and customer stakeholders/end … practices and modern architectural patterns, including microservices and message-driven architectures NFR/Non-Functional requirement understanding and experience developing applications with this in mind Application/Digital Services Design experience Experience in software engineering practices like Code Reviews, CI/CD Pipelines and SOLID/DRY principals Hands-on developing/coding role using the following technologies: Frontend … JavaScript/TypeScript or Angular or React or Node) Backend (Java, SpringBoot, Hibernate, Kotlin) Experience in estimation and sizing Integration experience API Design experience Cloud experience Appetite to work with emerging AI technologies SC Eligible Additional Information Why Version 1? At Version 1, we believe in providing our employees with a comprehensive benefits package that prioritises their wellbeing More ❯