26 to 50 of 165 API Design Jobs in London

Senior Developer - Azure Applications

Location
Greater London, England, United Kingdom
BDSthe company helps organisations deliver meaningful digital transformation through cloud, data, AI and cyber security. We work across the public and private sector to design and build technology solutions that make a genuine difference to users. We’re looking for an Azure Application Developer with strong API development … production ready solutions within Microsoft Azure. The RoleAs an Senior Developer at UBDS, you’ll work alongside developers, architects, DevOps and security engineers to design and build cloud native applications and APIs. This is a hands on role where you’ll take solutions from requirements and design through ...

Enterprise Software Architect

Location
Bromley, England, United Kingdom
enterprise and partner ecosystems. The position also plays a key role in shaping industry best practices and representing the organisation externally. Enterprise & Ecosystem Architecture Design and oversee the implementation of enterprise‐wide software architecture, spanning internal platforms, cloud environments, and external partner ecosystems Develop “big picture” architectural frameworks … adherence to security, compliance, regulatory, and quality standards Identify and mitigate long‐term architectural risks (e.g., vendor lock‐in, scalability constraints, regulatory exposure) Technical Design & Solution Development Conduct research, analyse data, gather requirements, and define end‐to‐end solutions Create architectural artefacts representing system functions, integrations, and user interfaces ...

Senior Software Engineer, Inference Platform

Location
Greater London, England, United Kingdom
after you’re helping with UI/UX, customer success, documentation and product ops. What You’ll Do Inference Platform Architecture & Core Services Design and build the company's inference service platform the backbone for serving AI models at scale across diverse workloads Own and architect core platform components … Gateway, Resource Orchestrator, Runtime Engines, and Autoscaler Design highly modular, scalable, and extensible low‐level designs (LLDs) for inference infrastructure components Lead high‐level design discussions, establish architectural patterns, and drive technical decision‐making for the inference stack Model Deployment & Lifecycle Management Understand and optimize the dynamics ...

Senior Java Developer

Hiring Organisation
CODEVERSE LIMITED
Location
London, South East England, United Kingdom
Employment Type
Full-Time
Salary
£300.00 - £400.00 per day
experienced Senior Java/Python Engineer to join a high-performing Agile engineering team delivering secure, highly available and scalable microservices and API platforms. You will be hands-on with modern engineering technologies, working across microservices, APIs, Kafka, cloud databases, containers and observability, while also providing technical leadership … mentoring junior engineers. Key Responsibilities Design and develop scalable Java/Python microservices and REST APIs. Build and operate event-driven solutions using Apache Kafka . Design and optimise AWS Aurora PostgreSQL databases and data platforms. Deploy and support applications using Docker and Kubernetes . Develop API ...

Python Technical Lead FinTech

Hiring Organisation
Run-Time Group Ltd
Location
City of London, London, United Kingdom
Employment Type
Permanent
major advantage. Key Responsibilities Technical Leadership Own the technical roadmap, guide architectural decisions, and ensure engineering excellence across backend services. Python Engineering Design and build robust, secure, and scalable microservices using Python (FastAPI, Django, Flask). System Architecture Lead the design of distributed systems, event-driven architectures … data intelligence. DevOps & Cloud Collaborate on CI/CD pipelines, containerisation (Docker, Kubernetes), and cloud deployments (AWS/GCP/Azure). Data & API Strategy Oversee API design, data modelling, and integration with internal and external financial systems. Security & Compliance Ensure systems meet regulatory, security, and audit ...

Full Stack Software Engineer (Senior)

Location
Greater London, England, United Kingdom
This Role We're hiring a senior full-stack engineer who owns real problems end-to-end and shapes how the team builds, from API design and frontend experience through to backend services, production reliability, and launch. You already use AI as part of how you think, build … test, and ship. You'll write code that moves money in production, design and modernize the platform across the stack, and lead delivery of customer-facing features as Xe rebuilds its platform layer. You'll work in a small engineering team with direct access to product, design ...

Senior Manager- Software Engineering

Location
Greater London, England, United Kingdom
will be a hands‐on technical leader who defines direction, raises engineering standards, and delivers measurable product outcomes, all while remaining deeply involved in design and development. This is not a traditional people‐management or delivery‐management role—here, you will write code, architect solutions, lead complex projects … role is perfect for leaders seeking high‐growth, product‐driven environments, who are passionate about distributed systems, and who want to directly influence the design of secure, scalable, and resilient infrastructure while cultivating top engineering talent. What You’ll Do: Architect and design scalable, resilient, high‐performance backend ...

frontend js/react/typescript for AI video platforms

Location
Greater London, England, United Kingdom
used by over 90% of the Fortune 100, and its proprietary generative AI technology is built in-house. Задачи: Build, scale and evolve the design system, including the component library, design tokens and documentation Extend the design system for AI-assisted development using Storybook and machine-readable … interfaces such as MCP Design component APIs that resist misuse by AI and human developers Write high-quality, performant frontend code with React and TypeScript Partner with design, product and engineering to define components and deliver production-ready solutions Make components accessible by default according to WCAG 2.2 ...

Solution Architect

Location
Greater London, England, United Kingdom
Solirius Reply, part of the Reply Group, is a technology consultancy and digital transformation partner that helps organisations solve complex challenges through strategy, design, engineering, and delivery. We work closely with our clients to deliver secure, accessible, user-focused services that evolve with their needs. By combining deep technical … expertise with people-centred design, we create solutions that deliver meaningful, lasting impact. Our consultants partner directly with client teams, embedding into organisations to understand their goals, challenges, and users. This collaborative approach enables us to deliver tailored solutions that drive measurable outcomes across public and private sectors. Past ...

Senior Software Engineer

Location
Greater London, England, United Kingdom
Defence delivery team. This is a versatile, high-impact role designed for funded client delivery: you will build mission-critical web applications and API backends for central MoD programmes, while contributing to low-level system integrations (Kotlin, Android ART, IPC/AIDL) on tactical edge and Situational Awareness … platforms. You will sit at the intersection of modern enterprise software engineering and tactical edge integration, ensuring all code meets MoD Secure by Design (SbD) principles and Def Stan 00-056 safety boundaries. Full-Stack Application Development: Design and build resilient, secure web applications, microservices, and APIs (TypeScript ...

Senior Software Engineer - API Enterprise - Full-Stack

Location
Greater London, England, United Kingdom
NVIDIA DGX SuperPODs to delivering real‐time Language AI to over 300 million users and 200,000+ businesses globally. You will join the API Enterprise team. We sit at the intersection of DeepL's API platform and our Enterprise ecosystem. Whereas the Core team obsesses over the self … that enterprise IT and security teams depend on. We work hand‐in‐hand with a wide set of stakeholder teams to make DeepL's API the obvious and safe choice for global enterprises. We are shifting gears. We are moving from "Software-First" to "Product-First. ...

Python Application Developer with DevOps

Location
Greater London, England, United Kingdom
environment Qualifications Hands-on experience in production environments as a Software Developer and DevOps/Platform Engineer Strong production experience with Python and software design patterns (SOLID, DRY) Expertise in AWS (or similar cloud providers), Containerization and Kubernetes Deep understanding of RESTful API or GraphQL API design ...

Senior Engineer

Location
Greater London, England, United Kingdom
solutions and enabling tangible value through technology. This role is a full-stack engineering role (covering frontend, backend, data, infrastructure) and collaborates on solution design, implementation, deployment, testing and support.**Responsibilities:*** Design, build, and improve modern application services that support a strategic business platform, with a focus … strong track record of delivering production systems.* Strong experience building backend applications and APIs, ideally in Java* Practical experience across service-based architecture, API design, integration patterns, and modern web application delivery.* Experience contributing to modernisation or platform evolution initiatives is strongly desirable.* Strong engineering discipline across testing ...

Solution Architect

Hiring Organisation
Hackajob Ltd
Location
South West London, London, United Kingdom
Employment Type
Permanent
public sector clients, helping to deliver Solirius' services to the highest standard. The role will involve working with multiple business stakeholders, helping them to design business solutions which will then be implemented by the delivery teams. As a Solution Architect, you will be expected to operate with a high … role will require innovative thinking, applying best practices and emerging technologies to solve complex business problems in creative and pragmatic ways. Requirements Key Responsibilities: Design end-to-end solution architectures that meet business, technical, and security requirements. Translate business and technical requirements into scalable, secure, and cost-effective designs. ...

Senior Engineer - Payments

Location
Greater London, England, United Kingdom
development of our next-generation platform channels. Partner on the delivery of new products while continuously maintaining and improving existing ones. Architecture & Design: Collaborate with team members and engineering leaders to design new services and components utilizing our internal Request for Comments (RFC) process. End-to-End Ownership … Micro Frontends (MFEs) is a major plus. DevOps & Cloud: Hands-on experience with Docker, Kubernetes, Terraform, and AWS. Foundations: Strong understanding of system architecture, API design, scalable service integration, Linux systems, and Git version control. Core Soft Skills: Strong knowledge of basic algorithms, object-oriented/functional design ...

Senior Backend Engineer - UK

Location
Greater London, England, United Kingdom
startup with experience building SaaS products. You will also have a deep understanding of the key challenges engineers face and a firm grasp on design principles in prioritizing key features and capabilities. Your superpower is how to bridge the gap between technical specifics and business needs effortlessly and turn … engineering mastermind behind Heidi developing AI products which will change the face of healthcare Autonomously deliver beautiful & robust code with considerations on code structure design and scalability. Implement and optimize data storage solutions. Design, build, and maintain high-performance backend systems using Python. Architect and manage cloud infrastructure ...

Senior Fullstack Developer — Java or Kotlin, React and TypeScript

Location
Greater London, England, United Kingdom
maintain high standards of engineering quality.**How you will make an impact*** Build and maintain reliable JVM-based services using Kotlin or modern Java.* Design and develop well-structured APIs and integrations.* Build reusable services, APIs and components that enable other teams to deliver consistently and reduce duplication.* Contribute … API design standards, documentation and versioning across services.* Deliver complete end-to-end features by connecting backend services and data models with responsive web interfaces.* Use appropriate test-first and test-informed practices to create effective automated tests.* Experiment with AI-assisted engineering tools where they provide clear ...

Senior Fullstack Developer — Java or Kotlin, React and TypeScript

Location
Greater London, England, United Kingdom
maintain high standards of engineering quality. How you will make an impact Build and maintain reliable JVM-based services using Kotlin or modern Java. Design and develop well-structured APIs and integrations. Build reusable services, APIs and components that enable other teams to deliver consistently and reduce duplication. Contribute … API design standards, documentation and versioning across services. Deliver complete end-to-end features by connecting backend services and data models with responsive web interfaces. Use appropriate test-first and test-informed practices to create effective automated tests. Experiment with AI-assisted engineering tools where they provide clear ...

Technical Lead - Java

Hiring Organisation
Sanderson Recruitment
Location
London, United Kingdom
Employment Type
Permanent
Salary
£95,000
helping shape modern platforms that leverage Agentic AI, workflow orchestration, and intelligent automation to solve complex business challenges. What You'll Do Lead the design and delivery of scalable Java 17+/Spring Boot microservices Own architecture decisions, system design, and engineering standards Design resilient, high-performance … adoption of AI engineering tools including GitHub Copilot, Cursor, and Claude Code Deliver AI-powered features using LLMs, RAG, semantic search, and intelligent automation Design workflow orchestration solutions using Camunda or similar BPM platforms Lead the implementation of Agentic AI capabilities, autonomous workflows, and AI-driven decision making Drive ...

Blockchain Software Developer - Digital Assets Platform

Location
Greater London, England, United Kingdom
engineering role for a developer who is deeply enthusiastic about the intersection of decentralized technologies and institutional finance.The successful candidate will contribute to the design, development, and deployment of **Web3-native** components and integrations that power Citi's digital asset infrastructure — spanning tokenization, smart contracts, on-chain settlement … Web3 engineering** fundamentals, a curiosity for emerging blockchain ecosystems, and the ability to bridge decentralized technology patterns with enterprise-grade software standards.**Key Responsibilities*** **Design, develop, and deploy** Web3 components and integrations for Citi's Digital Asset Platform, including smart contracts, on-chain event listeners, wallet integrations, and blockchain ...

Blockchain Software Developer - Digital Assets Platform

Location
Greater London, England, United Kingdom
role for a developer who is deeply enthusiastic about the intersection of decentralized technologies and institutional finance. The successful candidate will contribute to the design, development, and deployment of Web3-native components and integrations that power Citi's digital asset infrastructure — spanning tokenization, smart contracts, on-chain settlement … Web3 engineering fundamentals, a curiosity for emerging blockchain ecosystems, and the ability to bridge decentralized technology patterns with enterprise-grade software standards. Key Responsibilities Design, develop, and deploy Web3 components and integrations for Citi's Digital Asset Platform, including smart contracts, on-chain event listeners, wallet integrations, and blockchain ...

Principal Developer

Location
London, United Kingdom
delivery methodology to ensure timely and high-quality delivery of software applications. Technical Ownership: Take technical ownership of a product or software solution, covering design, estimation, shaping, and user story/requirement creation. Solution Documentation: Document solutions, including architecture, configuration, release, and support handover. Stakeholder Collaboration: Collaborate and liaise … practices and modern architectural patterns, including microservices and message-driven architectures. Non-Functional Requirements: Experience developing applications with non-functional requirements in mind. Application Design: Experience in application/digital services design. Software Engineering Practices: Proficiency in software engineering practices like code reviews, CI/CD pipelines, and SOLID ...

Principal Developer

Hiring Organisation
Hackajob Ltd
Location
South West London, London, United Kingdom
Employment Type
Permanent, Work From Home
Salary
£90,000
delivery methodology to ensure timely and high-quality delivery of software applications. Technical Ownership: Take technical ownership of a product or software solution, covering design, estimation, shaping, and user story/requirement creation. Solution Documentation: Document solutions, including architecture, configuration, release, and support handover. Stakeholder Collaboration: Collaborate and liaise … practices and modern architectural patterns, including microservices and message-driven architectures. Non-Functional Requirements: Experience developing applications with non-functional requirements in mind. Application Design: Experience in application/digital services design. Software Engineering Practices: Proficiency in software engineering practices like code reviews, CI/CD pipelines, and SOLID ...

Systems Developer

Hiring Organisation
Massenhove Recruitment Limited
Location
London, United Kingdom
Employment Type
Full-Time
Salary
£40,000 - £55,000 per annum
insurers alike. Ideal for a candidate who is driven to succeed, take ownership and pride in delivering exceptional levels of customer service. Key Accountabilities Design, develop, test, and maintain Python applications, scripts, and services Build and maintain APIs and integrations with third-party systems and internal platforms Write clean … technical solutions Participate in code reviews, sprint planning, and agile ceremonies Troubleshoot, debug, and resolve production issues in a timely manner Contribute to the design and optimisation of data pipelines and database interactions Support CI/CD pipeline development and deployment automation Write and maintain unit, integration, and regression ...

Software Engineer II - Cloud Platform Engineering - Chase UK

Location
Greater London, England, United Kingdom
developer experience, providing tools and infrastructure that support agile methodologies and continuous integration/continuous deployment. Identify problems, propose solutions, and execute software design, development, operations, and technical troubleshooting. Develop secure, high-quality full stack production code, and review and debug code. Support the products you build through … team culture of diversity, opportunity, inclusion, and respect. Required Qualifications, Capabilities, and Skills Practical knowledge of the full software development lifecycle, including system design, application development, testing, and operational stability. Ability to develop, debug, and maintain code using modern programming languages and database querying languages. Good understanding of Java ...