26 to 50 of 61 API Design Jobs in London

Software Engineering Team Lead .NET / C#

Hiring Organisation
McGregor Boyall
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£110,000 - £125,000 per annum
remaining close to complex technical problem-solving. Key Responsibilities Lead and develop a high-performing engineering team Own delivery outcomes, quality, and engineering standards Design and evolve distributed, event-driven systems Partner with architecture and senior engineering stakeholders Drive continuous improvement across tooling, CI/CD, and testing Communicate … experience leading engineering teams in an Agile environment Strong expertise in C# and modern .NET/.NET Core Experience building distributed, event-driven systems API design and development (REST, GraphQL) Relational databases (SQL Server, MySQL, or similar) Cloud platforms such as AWS or Azure Solid understanding ...

SAP BTP Lead

Hiring Organisation
DXC
Location
City of London, London, United Kingdom
Employment Type
Permanent, Work From Home
Youll collaborate with business and technical teams to drive innovation, modernize architectures, and maximize value from SAPs cloud technologies. What Youll Do: Lead architecture, design, and implementation of solutions using SAP BTP services such as SAP Build, Integration Suite, Event Mesh, AI Core, and HANA Cloud. Define clean-core … Guide teams in building custom apps, workflows, automations, and side-by-side extensions using CAP/RAP and low-code tools. Own integration and API strategies leveraging BTP Integration Suite (APIs, OData, REST/SOAP, event-driven patterns). Provide technical leadership, mentoring developers and ensuring adherence to coding ...

Senior Full-Stack Developer

Hiring Organisation
Goodman Masson
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£40,000 - £70,000 per annum
work across frontend and backend systems, help shape technical solutions, and ensure best practices are followed throughout the development lifecycle. Key Responsibilities Design, develop, and maintain high-quality software solutions across the full stack Build and integrate APIs, ensuring secure and efficient data exchange Develop user interfaces using modern … Requirements Proven experience as a full-stack developer Strong proficiency in .NET (C#), JavaScript, and modern frontend frameworks Solid experience with SQL databases and API design and integration Excellent problem-solving, communication, and organisational skills Ability to work proactively on independent projects and collaboratively within a team Familiarity ...

Managing Technical Architect

Hiring Organisation
TALENT INTERNATIONAL UK LTD
Location
London, UK
Employment Type
Full-time
Description: Managing Technical Architect (Microservices Design Evaluation & Strategy Recommendation) £700-£800 Inside IR35 (Depending on experience) 7 months contract Must be SC clearance eligible About the role: We are seeking a highly skilled Managing Technical Architect with proven central government experience to help our client deliver/assess … provide design assurance across a complex ecosystem comprising microservices, monoliths, singleton applications and distributed monoliths. The role requires deep Managing expertise in evaluating and optimising complex application ecosystems, with particular emphasis on microservice architectural principles and modernisation strategies. As a Managing Technical Architect you will be responsible for: Conduct ...

Senior Backend Engineer

Hiring Organisation
THE IDOLS GROUP LIMITED
Location
London, United Kingdom
Employment Type
Permanent
systems problems. Skills and experience Strong expertise in Python and modern backend frameworks Deep knowledge of relational databases, particularly PostgreSQL Strong understanding of RESTful API design and microservices patterns Experience working with cloud platforms and containerised environments (Docker, Kubernetes) Experience with CI/CD pipelines, automated testing ...

Senior Platform Software Engineer

Hiring Organisation
Caresoft Global Ltd
Location
Stratford, London, England, United Kingdom
Employment Type
Contractor
Contract Rate
£73.18 per hour
PubSub, Secret Manager). Observability: Experience implementing and utilizing observability and monitoring tools (e.g., Grafana, Splunk) to maintain system health and diagnose issues. API Design: Experience designing and developing REST APIs and associated QA tools. Engineering Practices: Passion for Software Craftsmanship with experience in Pair Programming, Mobbing ...

Junior Back-end Engineer

Hiring Organisation
ivee
Location
London Area, United Kingdom
maintain server-side logic using modern backend frameworks (e.g. Node.js, Python, Go) Work with APIs — designing, integrating, and maintaining RESTful endpoints Support database design and optimisation (e.g. PostgreSQL, MongoDB) Collaborate with front-end and product teams to deliver full-stack features Write clean, testable, and maintainable code Help improve ...

Senior AI Engineer

Hiring Organisation
Chambers and Partners
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
Competitive salary
drive smarter decisions and greater efficiency across Chambers and Partners. In this brand new role, role, as part of our Data team, you’ll design and implement intelligent systems that enhance how we use data, streamline operations, and power innovation across our digital platforms. You’ll play … Main Duties and Responsibilities Data & Retrieval Build robust ingestion pipelines for PDFs/Word/Excel/Audio/JSON and semi-structured sources. Design RAG systems: chunking strategies, document schemas, metadata, hybrid/dense retrieval, re-ranking, and grounding. Manage vector/keyword indexes (e.g., Azure AI Search ...

(Senior) Full Stack Engineer

Hiring Organisation
BioTalent
Location
City of London, London, United Kingdom
with potential leadership options A high-autonomy role within a technically rigorous environment Your Responsibilities Own and evolve the React and Next.js application architecture Design and implement scalable UI patterns for complex workflows and data visualisation Define state management strategies for long-running jobs and asynchronous systems Build clean … years of experience building production React applications - React, Next.js, TypeScript Experience deploying and managing applications on AWS using Infrastructure as Code and containerized workflows API Design experience UX/UI & Design systems Experience with state management at scale (e.g. React Query, Zustand, Recoil) Knowledge of authentication, authorisation ...

Senior PHP Full Stack Software Engineer - Supply Chain / Sustainability. Hybrid

Hiring Organisation
RecruitmentRevolution.com
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£70,000 - £80,000 per annum
want to expand this further - so you’ll help define best practice for AI-enabled engineering across the team. Key Responsibilities: • Lead the design, build and maintenance of custom Moodle plugins, themes and core feature enhancements • Write high-quality, secure, reusable PHP and deliver robust front-end experiences • Architect … across application + infrastructure layers and drive resolution • Lead performance optimisation and scalability improvements • Ensure compliance with accessibility standards, GDPR, and data protection by design • Strengthen QA processes and data integrity (including release readiness) Collaboration & Stakeholder Management: • Work closely with product and design to shape solutions (not just ...

Senior PHP Full Stack Software Engineer - Sustainability

Hiring Organisation
RecruitmentRevolution.com
Location
London, United Kingdom
Employment Type
Permanent
Salary
GBP 70,000 - 80,000 Annual
want to expand this further - so you ll help define best practice for AI-enabled engineering across the team. Key Responsibilities: • Lead the design, build and maintenance of custom Moodle plugins, themes and core feature enhancements • Write high-quality, secure, reusable PHP and deliver robust front-end experiences • Architect … across application + infrastructure layers and drive resolution • Lead performance optimisation and scalability improvements • Ensure compliance with accessibility standards, GDPR, and data protection by design • Strengthen QA processes and data integrity (including release readiness) Collaboration & Stakeholder Management: • Work closely with product and design to shape solutions (not just ...

Senior PHP Full Stack Software Engineer - Supply Chain / Sustainability. Hybrid

Hiring Organisation
Recruitment Revolution
Location
City of London, London, United Kingdom
Employment Type
Permanent, Part Time, Work From Home
Salary
£80,000
want to expand this further - so you'll help define best practice for AI-enabled engineering across the team. Key Responsibilities: • Lead the design, build and maintenance of custom Moodle plugins, themes and core feature enhancements • Write high-quality, secure, reusable PHP and deliver robust front-end experiences • Architect … across application + infrastructure layers and drive resolution • Lead performance optimisation and scalability improvements • Ensure compliance with accessibility standards, GDPR, and data protection by design • Strengthen QA processes and data integrity (including release readiness) Collaboration & Stakeholder Management: • Work closely with product and design to shape solutions (not just ...

Senior PHP Full Stack Software Engineer - Sustainability

Hiring Organisation
RecruitmentRevolution.com
Location
EC1V, Bunhill, Greater London, Old Street, United Kingdom
Employment Type
Permanent
Salary
£70000 - £80000/annum + Benefits
want to expand this further - so you’ll help define best practice for AI-enabled engineering across the team. Key Responsibilities: • Lead the design, build and maintenance of custom Moodle plugins, themes and core feature enhancements • Write high-quality, secure, reusable PHP and deliver robust front-end experiences • Architect … across application + infrastructure layers and drive resolution • Lead performance optimisation and scalability improvements • Ensure compliance with accessibility standards, GDPR, and data protection by design • Strengthen QA processes and data integrity (including release readiness) Collaboration & Stakeholder Management: • Work closely with product and design to shape solutions (not just ...

Backend Engineer (TypeScript/Ruby)

Hiring Organisation
Oliver Bernard
Location
City of London, London, United Kingdom
experiences at scale. Package 💷 £70–90k + 5% bonus 🏢 Hybrid (2 days onsite, London) What you’ll do Own the full lifecycle of services: API design, architecture, deployment, and production Build an internal platform delivering consistent, real-time communications across multiple digital touchpoints Collaborate with Product, Data, Marketing ...

Backend Engineer – Build Scalable, High‐Impact Financial Infrastructure

Hiring Organisation
Albert Bow
Location
London Area, United Kingdom
+ mobile applications Building and maintaining high‐performance APIs and distributed microservices Solving problems around scalability, reliability, security, and automation Working with modern API protocols including GraphQL and gRPC Enhancing the platform that connects both traditional and on‐chain financial services Must‐have experience: Strong backend engineering background with …/or Golang Solid understanding of microservices, event‐driven systems & distributed architecture Strong knowledge of PostgreSQL and/or Redis Understanding of web semantics, API design & backend web standards Proficiency with Git and version control workflows Experience with CI/CD, build automation and modern engineering pipelines Excellent ...

Senior Node/AWS Developer

Hiring Organisation
Method-Resourcing
Location
City of London, London, United Kingdom
Employment Type
Permanent
Salary
£80,000
impact The skills and experience my client are looking for: 5+ years of experience in software engineering, with expertise in Node.js and REST API design. Strong knowledge of AWS and serverless architecture. Strong experience with TypeScript, ensuring clean, efficient, and maintainable code. Experience with CI/CD pipelines using ...

Senior Node/AWS Developer

Hiring Organisation
Method Resourcing
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£80,000 per annum
impact The skills and experience my client are looking for: 5+ years of experience in software engineering, with expertise in Node.js and REST API design. Strong knowledge of AWS and serverless architecture. Strong experience with TypeScript, ensuring clean, efficient, and maintainable code. Experience with CI/CD pipelines using ...

AI Platform Engineer

Hiring Organisation
The Portfolio Group
Location
London, Castle Baynard, United Kingdom
Employment Type
Permanent
owning the cloud-native platform that underpins conversational AI and generative AI products at scale. Sitting at the core of AI delivery, you will design, build, and operate the runtime, infrastructure, and operational layers supporting RAG pipelines, LLM orchestration, vector search, and evaluation workflows across AWS and Databricks. Working … platform powering conversational assistants and generative AI products. Build, operate, and optimise RAG and LLM-backed services, improving latency, reliability, and cost. Design and run cloud-native AI services across AWS and Databricks, including ingestion and embedding pipelines. Scale and operate vector search infrastructure (Weaviate, OpenSearch, Algolia, AWS Bedrock ...

Product Engineer

Hiring Organisation
Affinity Labs
Location
City of London, London, United Kingdom
full-stack product delivery, from infrastructure and AI integrations through to React/React Native interfaces, collaborating closely with founders, creators, product, and design to turn lean specs into scalable, user-loved software. We’re looking for a strong generalist with backend depth and real mobile experience. Responsibilities Implement … mobile + web frontend → APIs → data models → integrations) while maintaining quality and velocity. Build React Native mobile apps and shared component systems across products. Design and ship scalable backend services (APIs, integrations, AI workflows). Run tight build → test → iterate → ship loops; provide realistic estimates and surface blockers early. ...

Senior Java Engineer – Reactive (Spring WebFlux)

Hiring Organisation
Fynity
Location
London Area, United Kingdom
senior individual-contributor role within a high-performing engineering team, building asynchronous, message-driven systems designed for scale, resilience, and near-zero downtime. Design and implement high-throughput, low-latency systems processing millions of real-time payment events Build event-driven architectures using modern Java and reactive frameworks Work … extensively with non-blocking I/O, asynchronous flows, back-pressure, and concurrency Contribute to system and API design, focusing on scalability, fault tolerance, and observability Collaborate closely with architects, engineers, and client teams across Europe Operate in Agile environments (Scrum/Kanban) with a strong engineering culture ...

Staff Engineer

Hiring Organisation
Corecom Consulting
Location
City of London, London, United Kingdom
Employment Type
Permanent
Salary
£110000 - £130000/annum
10+ years) Expert-level Python, with deep understanding of async patterns and performance optimisation Proven experience designing and scaling distributed systems Strong background in API design, data-intensive systems, and service architecture Track record of building platforms that operate reliably under heavy load Nice to have: Experience with ...

Back End Developer

Hiring Organisation
Prism Digital
Location
City of London, London, United Kingdom
that don’t yet have perfect answers. What You’ll Work With Python development at a high level FastAPI or adjacent Python backend frameworks API design and backend architecture fundamentals PostgreSQL and/or MongoDB React or React Native for frontend collaboration AWS serverless infrastructure Docker for bespoke ...

Mobile App Experience Layer Engineer

Hiring Organisation
ARM
Location
Stratford, London, United Kingdom
Employment Type
Contract
Contract Rate
£508 - £548/day Inside IR35
Experience - Java/Kotlin with Spring and Spring Boot - Google Cloud Platform (Cloud Run, Pub/Sub, Secret Manager) - Observability tools (Grafana, Splunk) - REST API design - TDD, pair programming, mobbing - Strong communication and mentoring - Git Preferred Experience - DevOps/CI/CD - Load & performance testing - Mobile integration experience ...

Senior Developer

Hiring Organisation
Reed.co.uk
Location
London, South East, England, United Kingdom
Employment Type
Contractor
Contract Rate
£80,000 per annum
development experience. Proven success in high-performing engineering teams in fast-paced environments. Deep expertise in development with: Python (Django, Flask, or FastAPI) PostgreSQL (design, optimisation, maintenance) Containerisation (Docker/Kubernetes) Event-driven architecture (Kafka/RabbitMQ) Nice to have experience with: TypeScript/JavaScript (NextJS, NodeJS, Tailwind) Terraform … DevOps Experience building and scaling SaaS platforms in production. Strong background in software architecture, microservices, and API design. Hands-on experience with AWS platform. Track record of delivering high-quality software under tight timelines. Strong communication skills, able to motivate and align technical teams. Experience with AI tools, APIs ...

Technical Data Architect

Hiring Organisation
Harnham - Data & Analytics Recruitment
Location
London, South East, England, United Kingdom
Employment Type
Full-Time
Salary
£80,000 - £95,000 per annum
digital content platform, shaping cloud infrastructure, data models, integrations, APIs and security across the solution. You'll work closely with the platform provider to design and govern a scalable architecture built on modern cloud services such as AWS, Azure or GCP, ensuring reliability, performance and compliance. A key responsibility … schemas and metadata structures, partnering with Solutions Architects to ensure all onboarding aligns with industry best practices. You'll champion best-practice patterns across API design, integration layers, authentication, data pipelines and cloud-native services, with hands-on involvement in troubleshooting and implementation support. The role also produces ...