25 of 25 API Design Jobs in Central London

Senior Software Development Engineer

Location
City Of London, England, United Kingdom
role in shaping our technical domain with the goal of powering all Expedia Group’s brands and product lines. In this role, you will: Design, build, and evolve robust, scalable, and secure backend services and applications, including clear low-level and high-level designs, APIs, data models, and explicit … pricing and offers experiences across Expedia Group brands. Lead end-to-end implementation of complex features and systems within the Offers Domain, from technical design and coding through testing, deployment, monitoring, and ongoing operational support, ensuring simple, accurate, and transparent pricing throughout the shopping and booking journey. Partner closely ...

Senior Engineering Manager — Hotels.com Technology

Location
City of Westminster, England, United Kingdom
support to do their best work. Join us and build for travelers everywhere. Expedia Group brands power global travel for everyone, everywhere. We design cutting‐edge tech to make travel smoother and more memorable, and we create groundbreaking solutions for our partners. Our diverse, vibrant, and welcoming community … loyalty, app and web experiences, and the platform capabilities underneath them. You will own technical direction and delivery for your team, drive system and API design for performance‐critical, high‐traffic customer‐facing services, and partner closely with Product, Design, Data, Marketing, and Platform teams in small ...

Software Development Engineer II - Full Stack

Location
City of Westminster, England, United Kingdom
every layout or content adjustment. In this role, you will: Develop React-based user interfaces and backend capabilities. Build, integrate, and contribute to API design decisions. Own features from understanding requirements through delivery, with support from teammates and product management. Collaborate with product management, backend and domain service … rollout of server-driven UI, enabling card layouts to be updated through configuration. Migrate traffic from legacy systems to the new platform. Apply API design considerations, including additional calls, traffic management, and error handling. Deliver reliable software with a rigorous development approach and a high quality bar. Experience ...

Integration Architect - Java, AWS, FS - OutsideIR35

Hiring Organisation
Sanderson Recruitment
Location
City of London, London, United Kingdom
Employment Type
Contract
Contract Rate
£550 - £600 per day + Outside IR35
connectivity across the clients core systems. Key Responsibilities: Own and evolve integration architecture aligned with enterprise standards Define and govern integration patterns across teams Design and deliver event-driven, API-first, and messaging solutions (NATS, REST) Lead end-to-end integration delivery, including hands-on development (Java/… Spring) Ensure scalable, cloud-native solutions on AWS Produce architecture artefacts (blueprints, contracts, ADRs) Guide teams on best practices, API governance, and event design Engage stakeholders and align cross-team integration efforts Primary Skills: Event-driven architecture and messaging systems (NATS, pub/sub, async patterns) API ...

Core Platform Developer

Location
City Of London, England, United Kingdom
Description: Role Overview We are seeking a Core Platform Developer to help design and build shared engineering foundations used across the firm. This role is focused on backend and platform capabilities that improve how internal teams build, integrate, deploy, and operate software. The ideal candidate is a strong software … patterns, and increase the reliability of internal systems. This person should be comfortable working across multiple areas of the stack, from service frameworks and API enablement to observability, governance, and developer workflows. This is a high-ownership role within a global, fast-moving engineering environment. Key Responsibilities Design ...

Senior Software Engineer

Hiring Organisation
The Portfolio Group
Location
City of London, London, United Kingdom
Employment Type
Permanent
Salary
£90000/annum
integration layer behind a new generation of AI-powered products. This is a genuinely full-stack engineering role, combining production-grade backend development, API design, AI integrations and frontend engineering. You'll work across the full application lifecycle, designing the services and interfaces that connect AI capabilities … products customers and colleagues use every day. You'll play a key role in building MCP integrations, agent-to-agent connectivity and robust API services, while also developing responsive, accessible interfaces in React and TypeScript. What you'll be doing Own the application and integration layer of AI products ...

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 ...

Senior Python Developer

Hiring Organisation
Tech 4
Location
City of London, London, United Kingdom
Employment Type
Permanent
play a key part in driving the adoption of AI across engineering, leveraging emerging technologies and embedding AI-native workflows to improve how they design, build, and deliver software. This role is predominantly hands-on, with around 2030% of time on technical leadership: architecture, mentoring, and shaping … generated code to our standards for security, reliability, and cost-efficiency (FinOps). These are first-class concerns in agentic pipelines, not afterthoughts. Design, build, and operate software across our platform, applying the same rigour to AI-augmented work as to anything else you ship. Embed deeply with Product ...

Senior Software Developer

Hiring Organisation
Youngs Employment Services
Location
WC2H, Covent Garden, Greater London, United Kingdom
Employment Type
Permanent
Salary
£65000 - £75000/annum Bonus
senior engineering role and you'll be joining at a point where the architecture, delivery approach and product direction still matter. You'll design and ship production services, contribute to a structured strangler-fig migration, and use AI-assisted development tools such as Cursor and Claude Code as part … suit an experienced Senior Developer, or a strong Developer ready to step up in a collaborative, senior-led environment. What You'll Be Doing Design, build and support cloud-based services in .NET 10 across Azure API Management, Azure SQL and the wider Azure platform. Help modernise ...

Principal Software Developer (Web)

Location
City Of London, England, United Kingdom
from an MVP to a comprehensive companion to the desktop application, as well as continuing the evolution of our Mobile app. Responsibilities Design & Build: Deliver robust, maintainable features across the stack (Scala/Play backend, React/AG-Grid frontend) Mobile Migration: Define the path from Codename … preferred, but not required)experience with Scala/Java preferred, but not required) Mobile Capability: Experience building or maintaining cross-platform Mobile Apps Architecture & Design: Solid grasp of API design, web & mobile architecture, as well as good UX design. Communication: Clear, pragmatic communicator who collaborates well with ...

Infrastructure Developer

Location
City Of London, England, United Kingdom
services and automation that connect complex infrastructure environments. The wider goal is to remove manual infrastructure processes and replace them with reliable, self-service, API-driven services. You will design and develop integrations across areas including bare-metal compute, networking, storage, cloud and workload platforms. A major part … role will involve building API services around a central CMDB, creating a reliable source of truth that can drive automated provisioning, configuration and infrastructure lifecycle management. Responsibilities will include: Building production-grade services and automation primarily in Python Designing REST APIs and integration layers across infrastructure platforms Developing CMDB ...

Chanel ERP Ecosystem Architect

Location
City Of London, England, United Kingdom
driving alignment across various teams with different priorities, ways of working to achieve solution standardisation. You sit at the intersection of business strategy, solution design, and delivery execution, shaping how D365 integrates and evolves globally. You work closely with integration architects, solution architects, developers, engineering/product teams … event‐driven patterns. Review and approve specifications, customisations, and integrations that impact end to end process flows across multiple systems. Facilitate cross‐system design alignment with solution owners (POS, WMS, EDI, middleware, data platform, identity/security), ensuring decisions are understood, documented, and governable. Support environment and build strategy ...

Technical Product Manager

Location
City Of London, England, United Kingdom
integrations that embed Xapien in the processes our customers already use. This is a hands-on product role for someone who is comfortable reading API docs, sketching data flows, and debating trade-offs with engineers — then translating all of it into a roadmap that commercial teams and enterprise customers … requirements with engineering (security, compliance, scalability) and support customers and partners through implementation. Establish success metrics for integrations and iterate based on real usage. API/MCP Own the product direction for Xapien's configuration API and MCP capabilities — how customers and AI agents programmatically configure ...

Technical Lead (Front Office Asset Management Tech Stack)

Location
City Of London, England, United Kingdom
technical leadership across the Front Office application portfolio, ensuring solutions are aligned with business strategy, architectural standards, and operational requirements Lead the design, development, implementation, and support of technology solutions that enable investment, trading, portfolio management, and related business capabilities Partner with Product Owners, business stakeholders, architects, and engineering … platform simplification, application resiliency, automation, and AI-enabled capabilities Act as the primary technical authority for the application suite, making informed decisions on architecture, design patterns, technology selection, and engineering best practices Manage technical deliveries across multiple concurrent initiatives, ensuring successful execution, risk management, stakeholder communication, and high-quality ...

Technical Lead

Location
Westminster, West End, United Kingdom
technical leadership across the Front Office application portfolio, ensuring solutions are aligned with business strategy, architectural standards, and operational requirements Lead the design, development, implementation, and support of technology solutions that enable investment, trading, portfolio management, and related business capabilities Partner with Product Owners, business stakeholders, architects, and engineering … platform simplification, application resiliency, automation, and AI-enabled capabilities Act as the primary technical authority for the application suite, making informed decisions on architecture, design patterns, technology selection, and engineering best practices Manage technical deliveries across multiple concurrent initiatives, ensuring successful execution, risk management, stakeholder communication, and high-quality ...

Senior Scala Engineer CGEMJP

Location
City Of London, England, United Kingdom
Attribute Reputation services (APIs) to Digital services to provide attribute insights for fraud detection and prevention across the business. This work involves: Help design a future vision for our Att Rep services, including consolidation, to allow us to provide a consistent and easy to use experience for users. Consideration … maintenance efforts through incremental re-architecting - e.g. reducing the number of technologies that are required to support the pipeline & using managed services where appropriate. Design and develop clean functioning, testable code on the back-end, write effective APIs, develop and manage well-functioning databases and applications with security ...

Senior Scala Engineer CGEMJP00355784

Hiring Organisation
Experis
Location
West End, London, Stratford and New Town, United Kingdom
Employment Type
Contract
Contract Rate
£590 - £637/day
Attribute Reputation services (APIs) to Digital services to provide attribute insights for fraud detection and prevention across the business. This work involves: Help design a future vision for our Att Rep services, including consolidation, to allow us to provide a consistent and easy to use experience for users. Consideration … maintenance efforts through incremental re-architecting - e.g. reducing the number of technologies that are required to support the pipeline & using managed services where appropriate. Design and develop clean functioning, testable code on the back-end, write effective APIs, develop and manage well-functioning databases and applications with security ...

Scala Engineer

Location
City Of London, England, United Kingdom
Responsibilities Help define and deliver the future vision for attribute reputation services, driving simplification and consolidation where appropriate. Design and develop high-volume, high-availability, low-latency backend services. Enhance and optimise existing applications and services. Support incremental re-architecting initiatives to reduce technical complexity and improve maintainability. Develop … clean, testable and maintainable code using Scala and modern engineering practices. Design, build and maintain secure APIs, databases and applications. Collaborate with Product Owners, Business Analysts, Data Engineers and wider technical teams to deliver effective software solutions. Contribute to service support and operational excellence within a "build ...

Principal Software Engineer - C#

Location
City Of London, England, United Kingdom
Role Overview ICRV are seeking an exceptional Principal Engineer to own the architecture, design and hands‐on delivery of a desktop platform automating and streamlining trading desk workflows. This is a high‐visibility player‐coach role that may evolve to include formal people management. Role Responsibilities … output. Own the technical direction of the ICRV greenfield project, developing high‐performance, scalable, and robust solutions from first principles through to production operation. Design for hard non‐functional requirements: latency and responsiveness budgets as acceptance criteria, crash containment, least‐privilege isolation between sub‐applications. Work effectively with ...

C# .NET Developer – 11851

Location
City Of London, England, United Kingdom
joining an established team where you’ll have the opportunity to work alongside other Junior and experienced developers, contributing to the design and development of new applications and features, and help maintain and improve existing systems. Responsibilities: Develop, test, and deploy efficient, scalable, and maintainable applications using C# … . 2 – 5 years of professional experience in backend development. Strong proficiency in C# and .NET Core (latest versions). Solid understanding of RESTful API design and integration. Familiarity with CI/CD pipelines and Git for version control and continuous integration. Excellent problem-solving and analytical skills ...

Principal Software Engineer - C#

Location
City Of London, England, United Kingdom
team that executes complex, multi-leg synthetic strategies on behalf of institutional clients.Role OverviewICRV are seeking an exceptional Principal Engineer to own the architecture, design and hands-on delivery of desktop platform automating and streamlining trading desk workflows. This is a high-visibility player-coach role: you will apply … C#/.NET (LTS): back-end services with ASP.NET Core.Experience designing and delivering event-driven, service-oriented back-end systems (message brokers, async workflows, API design) in a production trading environment.Experience building desktop applications that host web content (e.g., Electron, Tauri, or custom .NET host); comfortable with WebSocket ...

Software Engineer

Hiring Organisation
Platform Recruitment
Location
City of London, Greater London, United Kingdom
Employment Type
Permanent
Salary
£90000 - £160000/annum
heavily backend-biased position but given the size of the team you will be working across the stack when needed Build scalable, performant systems Design and deliver end-to-end features with direct impact on customer value Work with product and ML teams to help translate abstract and complex … software function About you: Strong ability across scalable and performant systems You have a product mindset Statically typed language expertise Experience with API design Low ego and love of engineering Full details are available. Please don't hesitate to reach out for more information. ...

Technical Product Manager

Location
City Of London, England, United Kingdom
investigates that data, and the APIs and integrations connecting it with customers’ existing systems. This is a hands-on role for someone comfortable reading API documentation, mapping data flows and working through technical trade-offs with engineers. You’ll take problems from early discovery through to delivery and adoption … functional requirements, including security, compliance and scalability. Own the direction of customer-facing APIs and emerging agent-based capabilities. Contribute to decisions around API design, versioning, backwards compatibility and developer experience. Create clear documentation and examples for technical customers and partners. Lead discovery using customer conversations, product data ...

Technical Product Manager: AI Data, APIs & Integrations

Location
City Of London, England, United Kingdom
seeking a technically minded Product Manager to own the data sources, APIs and integrations at the heart of our platform. You will read API documentation, map data flows and work through technical trade-offs with engineers, translating detail into a roadmap that engages both engineering and commercial stakeholders. … lead discovery through to delivery, shaping API design and data ingestion for a range of customer use cases. #J-18808-Ljbffr ...

Red Team Engineer

Location
City Of London, England, United Kingdom
growing need to track new threats, develop new defences and deploy in a timely and efficient manner. How you can make an impact Design and execute Red Team Operations against iProov’s biometric platform, web apps, APIs, identity flows Strengthen the company’s security posture through offensive security assessments … reduction. Bring insight into all aspects of modern security issues to our products and rapidly developing prototypes for mitigations. Mentor engineers in secure-by-design patterns, client-side security, and secure API design. Work hand-in-hand with developers to propose pragmatic mitigations, remediation plans, and detection logic ...