1 to 25 of 39 API Design Jobs in London

Software Architect

Hiring Organisation
X4 Group
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
Competitive salary
business-critical integration platform. Partner with senior technology stakeholders to ensure alignment with enterprise architecture principles and future technology strategy. Define architecture standards, design patterns, and engineering best practices. Provide hands-on technical leadership while remaining actively involved in solution design and development. Design secure, scalable, event … large-scale enterprise environments. Strong software engineering background with C# and .NET Core. Experience designing and implementing microservices architectures. Strong understanding of Domain-Driven Design (DDD). Expertise in API design, security, governance, and API Management technologies. Experience with messaging technologies such as RabbitMQ, Kafka ...

Java Developer - Payments

Hiring Organisation
Huxley Associates
Location
City of London, London, United Kingdom
Employment Type
Permanent
Salary
£80000 - £130000/annum
senior individual contributor who combines hands-on Java development with architectural leadership, remaining close to implementation and setting the technical standard through design, code-level guidance, and practical problem solving. Design, build, and evolve highly available, high-throughput, zero-downtime systems and internet-facing APIs that can scale … securely for large retail and external client volumes. Lead architectural decisions across API design, domain modelling, integration patterns, resilience, observability, and operational robustness, ensuring the platform is fit for 24/7 global production use. Work across multiple software engineering teams to drive consistency in engineering standards, development ...

Lead Solution Architect Endur (ETRM Gas & Power Trading)

Hiring Organisation
BP Energy
Location
South West London, London, United Kingdom
Employment Type
Work From Home
improved valuation,, internal market and others) are architecturally coherent, reusable and aligned with bp's enterprise technology strategy. Establish and chair the GPTI Architecture Design Authority, governing all significant change through structured reviews, design challenges and sign-off gates. Influence and advise VP/SVP-level stakeholders … through risk analytics (VaR, Greeks, Monte Carlo, stress testing), P&L attribution, settlement, invoicing, confirmations and regulatory reporting (REMIT, EMIR, MiFID II, ACER). Design and govern the market connectivity architecture, covering exchange connectivity, broker interfaces, electronic trading platforms, TSO/DSO nomination interfaces and real-time price feeds. ...

Lead Solution Architect Endur (ETRM Gas & Power Trading)

Hiring Organisation
17918
Location
London, United Kingdom
improved valuation,, internal market and others) are architecturally coherent, reusable and aligned with bp's enterprise technology strategy. Establish and chair the GPTI Architecture Design Authority, governing all significant change through structured reviews, design challenges and sign-off gates. Influence and advise VP/SVP-level stakeholders … through risk analytics (VaR, Greeks, Monte Carlo, stress testing), P&L attribution, settlement, invoicing, confirmations and regulatory reporting (REMIT, EMIR, MiFID II, ACER). Design and govern the market connectivity architecture, covering exchange connectivity, broker interfaces, electronic trading platforms, TSO/DSO nomination interfaces and real-time price feeds. ...

Senior Full Stack Developer (React & C#.NET)

Hiring Organisation
Adecco
Location
London, United Kingdom
Employment Type
Contract
Python (pyspark): Experience with data pipelines and analytics is a plus. Power BI: Familiarity with developing dashboards and data models. Architecture: Knowledge of microservices, API design, and event-driven architectures. DevOps/CI/CD: Experience with Azure DevOps, GitLab, GitHub Actions, or similar tools. Cloud Platforms: Proficient … Azure preferred). Databases: Strong skills in SQL Server, PostgreSQL, or other relational databases. containerisation: Experience with Docker and Kubernetes. Key Responsibilities Design & Develop: Create and maintain full stack applications using React JS and C#.NET Core. Build Services: Develop high-performance backend services and RESTful APIs with a focus ...

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 Developer

Hiring Organisation
Reed.co.uk
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£90,000 per annum
venture backed by the strength and stability of an established business. Key Responsibilities End-to-end development of high-quality, scalable SaaS platforms from design through deployment and maintenance. Architect and implement robust backend services primarily using Python and PostgreSQL. Develop and maintain responsive, performant front-end applications with … Provide technical mentorship and leadership to development teams, fostering best practices in coding, testing, and deployment. Participate in code reviews, architecture discussions, and system design decisions. Troubleshoot and resolve complex technical issues across the full stack. Ensure software security, scalability, and performance are maintained at all times. Keep abreast ...

AWS Solution Architect (Senior Manager)

Hiring Organisation
Anson Mccade
Location
City of London, London, United Kingdom
Employment Type
Permanent
high-performing cloud practice. This is an opportunity to work at the forefront of cloud transformation, partnering with tier-one clients across industries to design and deliver innovative, scalable, and secure AWS solutions. Youll play a pivotal role in shaping enterprise cloud strategies while leading complex transformation programmes. … strategy Certifications & Education AWS Certification (Associate or Professional e.g. Solutions Architect, DevOps Engineer) Degree in Computer Science, Engineering, or related discipline Technical Expertise Architecture & Design Translating business needs into scalable cloud architectures Cost optimisation and cloud best practices Data & AI Experience with data platforms, analytics, and AI/ ...

Backend Engineer

Hiring Organisation
Robert Half
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
Salary negotiable
systems that enable global commerce, while evolving an existing real-time platform to support new markets. You will address backend capacity constraints and help design a shared transaction and ledger layer used across multiple business lines. This is a hands-on senior engineering role requiring both high-quality delivery … strong technical leadership in ambiguous, high-scale environments. You will be expected to: Design scalable systems with correctness and failure modes considered from the outset Clarify and scope requirements before proposing solutions Make pragmatic trade-offs in system design, avoiding over-engineering Operate independently without reliance ...

Java Technical Lead

Hiring Organisation
Adecco
Location
Wembley, London, England, United Kingdom
Employment Type
Full-Time
Salary
£80,000 - £85,000 per annum
best practice implementation across: Stateless architecture Health check endpoints Secure secret management (Azure Key Vault) Containerisation standards and deployment readiness The Integration Engine Lead API and integration strategy, including: RESTful API design OAuth2 authentication flows (including FusionAuth) Event-driven systems via Azure Service Bus Transactional email logic ...

Solutions Architect

Hiring Organisation
Euro Car Parks
Location
Central London, London, United Kingdom
Employment Type
Permanent
Ireland providing specialist services to a wide range of blue-chip clients. The role We are seeking technical polyglots who enjoy both technical architectural design, hands-on coding and peer reviews, though also like the idea of the equally important social/client-facing aspect of the role. … development architecture as well as supporting business analysts and product owners in planning and story-mapping for new development. You will act as technical design authority (TDA) for delivery of technical stories and produce technical documentation artefacts to support the delivery process. Main Responsibilities Duties will include: The design ...

Java / Cloud Technical Lead - London, Wembley

Hiring Organisation
Adecco
Location
London, United Kingdom
Employment Type
Permanent
Salary
£75000 - £80000/annum + Benefits
just familiarity, but production ownership. Azure Integration: Proven experience building applications that consume Azure-native services, including Azure Key Vault for secrets, Azure Storage API, and Azure Service Bus for event-driven messaging. DevOps Mindset: Solid understanding of the full CI/CD lifecycle; comfortable reading and contributing … Dockerfiles and GitHub Actions YAML workflows - not as a DevOps engineer, but as a developer who understands the pipeline their code flows through. API Mastery: Deep expertise in RESTful API design principles, OAuth2 authentication flows (including FusionAuth integration), and DMARC-compliant transactional email logic via SendGrid. Duties ...

Lead Java Modernization Engineer - London, Wembley

Hiring Organisation
Adecco
Location
London, United Kingdom
Employment Type
Permanent
Salary
£75000 - £80000/annum + Benefits
just familiarity, but production ownership. Azure Integration: Proven experience building applications that consume Azure-native services, including Azure Key Vault for secrets, Azure Storage API, and Azure Service Bus for event-driven messaging. DevOps Mindset: Solid understanding of the full CI/CD lifecycle; comfortable reading and contributing … Dockerfiles and GitHub Actions YAML workflows - not as a DevOps engineer, but as a developer who understands the pipeline their code flows through. API Mastery: Deep expertise in RESTful API design principles, OAuth2 authentication flows (including FusionAuth integration), and DMARC-compliant transactional email logic via SendGrid. Duties ...

Java Technical Lead

Hiring Organisation
Michael Page
Location
London, United Kingdom
Employment Type
Permanent
Salary
£80000 - £90000/annum
manage technology teams to deliver high-quality software solutions. Collaborate with stakeholders to understand business requirements and translate them into technical deliverables. Oversee the design, development, and implementation of technical solutions. Ensure best practices in coding, testing, and deployment are followed. Provide technical mentorship and guidance to team members. … modern Java (17+) is non-negotiable. 2+ years leading engineering teams or operating as a tech lead/lead engineer with ownership of design and delivery outcomes. Deep Spring Boot expertise: REST APIs, Spring Security, Spring Data, Spring Cache; proven ability to set patterns others follow. Strong command ...

Senior Python Engineer (Django / DevOps / IaC)

Hiring Organisation
Pontoon
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
£850 per day
cloud-native systems across the business by making security tooling fast, reliable, and seamless for every development team. You will be responsible for Design, develop, and maintain scalable REST APIs using Django. Build and operate asynchronous task pipelines (Celery/Redis) that orchestrate security scanning at scale. Ensure best … practices for code quality, performance, and security. Integrate robust security practices into all API layers, including authentication, authorisation, data validation, and protection against vulnerabilities. Develop and manage CI/CD pipelines for automated testing, deployment, and monitoring. Work closely with core devops teams or independently handle infrastructure and deployment ...

Integration Developer FTC

Hiring Organisation
itecopeople
Location
London, United Kingdom
Employment Type
Permanent, Work From Home
Salary
£60,000
using modern cloud-native and streaming technologies. Key Responsibilities Develop event-driven integrations and backend services Build connectors, event-processing services, and data pipelines Design scalable integration patterns, schemas, and event flows Develop CDC pipelines and resilient messaging solutions Improve observability through logging, metrics, and tracing Deploy containerised services … Grafana Required Skills Strong software engineering background Experience building integration or event-driven platforms Kafka, Redpanda, or similar streaming technologies Enterprise system integrations and API design Agile development experience Strong communication and collaboration skills Desirable Skills Go and/or Python CDC pipeline development Azure cloud experience Observability ...

AI Platform/ DevOps Engineer

Hiring Organisation
The Portfolio Group
Location
City of London, London, Castle Baynard, United Kingdom
Employment Type
Permanent
Salary
£70000 - £80000/annum + Benefits
secure, and cost-efficient platform infrastructure that enables AI engineering teams to ship and operate AI products reliably in production. What you'll do Design, build, and operate cloud-native AI platform infrastructure across AWS (Lambda, API Gateway, DynamoDB, S3, CloudWatch) and Databricks Deploy and operate containerised services … workflows, and RAG components Implement observability across AI workloads using CloudWatch, MLflow, and OpenTelemetry - covering latency, throughput, cost, and system health Apply secure-by-design principles including IAM, encryption, network controls, and audit logging Work closely with AI engineers to translate prototypes and proof-of-concepts into production-ready ...

Senior C# Engineer - Agentic Engineering, .NET 9, AWS Lamba & SQS

Hiring Organisation
Smart Sourcer Limited
Location
City of London, London, United Kingdom
Employment Type
Contract
Contract Rate
From £750 to £800 per day
with the ability to architect and lead distributed REST microservices at scale. Strong authority in AWS serverless : Lambda-first, with hands-on experience across API Gateway, SQS, Step Functions, EventBridge and IAM. Practical experience with Claude Code (or similar) and advanced agentic workflows multi-agent orchestration, context management, custom … commands/skills, and scaling AI-assisted delivery. Deep data expertise across Aurora MySQL and DynamoDB schema design, access patterns, indexing, query tuning, and pragmatic trade-offs around consistency, scale and cost. Proven ability to design event-driven systems with SQS: idempotency, retries, ordering, DLQs and operational robustness. ...

Full Stack Developer

Hiring Organisation
Robert Half
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
Salary negotiable
this is an opportunity to help shape the future of a rapidly evolving platform. Role The Full Stack Developer will contribute to full-stack design and development across the platform. Design, develop, and maintain both front-end user interfaces and back-end services, APIs, and databases. Monitor platform … strong focus on backend development. Bachelor's or Master's degree in Computer Science, Engineering, or a related discipline. Strong understanding of database design, data modelling, and optimisation, particularly using SQL. Hands-on experience working with Google Cloud Platform (GCP) services. Experience monitoring production systems, triaging issues, and distinguishing ...

Manager - Lead AI Engineer

Hiring Organisation
Anson Mccade
Location
City of London, London, United Kingdom
Employment Type
Permanent, Work From Home
Salary
£70,000
building and knowledge-sharing initiatives Skills & Experience Required Significant senior backend development experience with strong Python proficiency (async programming, concurrency, multithreading) Expertise in RESTful API design, OpenAPI/Swagger documentation and API lifecycle best practices Hands-on experience with ML libraries: PyTorch, PySpark, scikit-learn, Hugging Face … machine learning, cloud computing or data engineering highly advantageous Professional accounting qualification desirable but not required Nice to Have Experience with Microsoft Graph API Background in audit, financial services or regulated industry technology What's on Offer A competitive salary and benefits package, flexible hybrid working across 20+ ...

Enterprise Architect - 6 months - Hybrid - INSIDE IR35

Hiring Organisation
Harvey Nash
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£650 - £700 per day
months - Hybrid - INSIDE IR35 I am working with a client who are seeking an experience Enterprise Architect with strong background in leading the architectural design for the replacement of legacy systems (ORACLE) Key Responsibilities: 'As-Is' Architecture Baseline Target State Design Integration Strategy & API Design Transition ...

Back-End Development Lead

Hiring Organisation
Oyster Consultant
Location
South East London, London, United Kingdom
Employment Type
Permanent, Work From Home
Salary
£80,000
evolve our stack and make constant improvements. Required Skills/Experience Strong C# development experience Experience with both .NET Core and .NET Web API Experience of building Microservices in .Net Core Experience using Message Based Architectures Experience using both SQL & NoSQL technologies Experience of API design Cloud ...

Software Engineer

Hiring Organisation
Corpay
Location
Central London, London, United Kingdom
Employment Type
Permanent, Work From Home
division. This position falls under our Cross Border line of business and is located in London. In this role, you will contribute to the design and development of our eMoney and FX payment systems. You will report directly to the Engineering Manager and collaborate closely with Product, Design … will set you up for success by providing: Assigned workspace or home office setup Company-issued equipment Role Responsibilities Provide significant contribution to the design, development, and maintenance of secure and scalable payment systems. Collaborate with engineering managers, designers, and product teams to gather and analyse requirements, implement technical ...

Full Stack Engineer

Hiring Organisation
Total Recruitment Group
Location
West London, London, United Kingdom
Employment Type
Permanent
Salary
£85,000
role, with strong backend expertise in Typescript and Node and front capability in React Proficiency in SQL, Redux, cloud services (AWS or GCP), RESTful API design and GraphQL Strong analytical skills with the ability to design, optimise, and troubleshoot complex UIs Excellent communication and leadership skills; ability ...

Senior Full Stack Engineer (GCP, Python, JavaScript) Remote

Hiring Organisation
Exalto Consulting
Location
London, United Kingdom
Employment Type
Contract
Contract Rate
£400 - £410/day
assisted development workflows. ● Agile Experience: Proven track record working within Agile teams and participating in iterative delivery. ● Core Engineering: Proficiency in Git, REST API design, and modern CI/CD practices This is a great opportunity to work for an exciting organisation and to start ASAP. The role ...