51 to 75 of 115 API Design Jobs in England

Senior Backend Developer (.NET | AI-First SaaS Platform)

Hiring Organisation
Keepnet
Location
Stevenage, Hertfordshire, UK
Employment Type
Full-time
that power these systems, working in a multinational, AI-first engineering team where quality, ownership, and long-term thinking matter. What You'll Do Design, build, and maintain scalable backend services for Keepnet's Human Risk Management platform. Build clean, modular APIs that integrate internal services and third-party … enable automation, reporting, and security workflows. Develop testable, maintainable codebases using principles such as Clean Architecture, DDD, and TDD. Own the full development lifecycle: design, implementation, CI/CD (Azure), and post-release monitoring. Work on distributed and asynchronous systems using message queues, background workers, and event-driven workflows. ...

Senior Backend Developer (.NET | AI-First SaaS Platform)

Hiring Organisation
Keepnet
Location
Chelmsford, Essex, UK
Employment Type
Full-time
that power these systems, working in a multinational, AI-first engineering team where quality, ownership, and long-term thinking matter. What You'll Do Design, build, and maintain scalable backend services for Keepnet's Human Risk Management platform. Build clean, modular APIs that integrate internal services and third-party … enable automation, reporting, and security workflows. Develop testable, maintainable codebases using principles such as Clean Architecture, DDD, and TDD. Own the full development lifecycle: design, implementation, CI/CD (Azure), and post-release monitoring. Work on distributed and asynchronous systems using message queues, background workers, and event-driven workflows. ...

Senior Backend Developer (.NET | AI-First SaaS Platform)

Hiring Organisation
Keepnet
Location
Bath, Somerset, UK
Employment Type
Full-time
that power these systems, working in a multinational, AI-first engineering team where quality, ownership, and long-term thinking matter. What You'll Do Design, build, and maintain scalable backend services for Keepnet's Human Risk Management platform. Build clean, modular APIs that integrate internal services and third-party … enable automation, reporting, and security workflows. Develop testable, maintainable codebases using principles such as Clean Architecture, DDD, and TDD. Own the full development lifecycle: design, implementation, CI/CD (Azure), and post-release monitoring. Work on distributed and asynchronous systems using message queues, background workers, and event-driven workflows. ...

Senior Backend Developer (.NET | AI-First SaaS Platform)

Hiring Organisation
Keepnet
Location
Cambridge, Cambridgeshire, UK
Employment Type
Full-time
that power these systems, working in a multinational, AI-first engineering team where quality, ownership, and long-term thinking matter. What You'll Do Design, build, and maintain scalable backend services for Keepnet's Human Risk Management platform. Build clean, modular APIs that integrate internal services and third-party … enable automation, reporting, and security workflows. Develop testable, maintainable codebases using principles such as Clean Architecture, DDD, and TDD. Own the full development lifecycle: design, implementation, CI/CD (Azure), and post-release monitoring. Work on distributed and asynchronous systems using message queues, background workers, and event-driven workflows. ...

Senior Backend Developer (.NET | AI-First SaaS Platform)

Hiring Organisation
Keepnet
Location
Chesterfield, Derbyshire, UK
Employment Type
Full-time
that power these systems, working in a multinational, AI-first engineering team where quality, ownership, and long-term thinking matter. What You'll Do Design, build, and maintain scalable backend services for Keepnet's Human Risk Management platform. Build clean, modular APIs that integrate internal services and third-party … enable automation, reporting, and security workflows. Develop testable, maintainable codebases using principles such as Clean Architecture, DDD, and TDD. Own the full development lifecycle: design, implementation, CI/CD (Azure), and post-release monitoring. Work on distributed and asynchronous systems using message queues, background workers, and event-driven workflows. ...

Solutions Architect

Hiring Organisation
Addition
Location
Milton Keynes, Buckinghamshire, England, United Kingdom
Employment Type
Full-Time
Salary
£60,000 - £71,000 per annum
high-impact transformation programs that drive innovation and business success. In this dynamic, full-time position based in Milton Keynes, you will lead the design and delivery of cutting-edge architecture solutions across strategic initiatives such as Contract Management Transformation, Fleet Programmes, and Digital Innovation. Collaborate with global teams … enterprise integration, messaging models, and Agile/Lean practices Experience with EA tools (LeanIX, Alfabet, Bizzdesign, Sparx EA) Cloud platform expertise (AWS, Azure) API design, event-driven and microservices architectures Understanding of SOAP, REST, and modern integration patterns Ability to produce detailed technical designs for diverse audiences Experience ...

Senior Software Developer

Hiring Organisation
Oscar Associates (UK) Limited
Location
Warrington, Cheshire, North West, United Kingdom
Employment Type
Permanent
Salary
£55,000
Stack Developer - Remote - Competitive Salary I'm working with an exciting organisation that is looking to appoint a Senior Full Stack Developer to help design and deliver secure, cloud-native applications within a modern Microsoft and Azure ecosystem. This is an excellent opportunity for an experienced full-stack engineer … maintaining unit and frontend tests (NUnit and ViTest) Contributing to CI/CD pipeline improvements and secure deployment practices Participating in architecture and technical design reviews Ensuring all development aligns with OWASP security best practices Tech Stack & Environment Core technologies: .NET 10/ASP.NET Core Angular 21 (mandatory) DevExpress ...

Senior .Net Developer

Hiring Organisation
ISR RECRUITMENT LIMITED
Location
South West, United Kingdom
Employment Type
Permanent
Salary
£55000 - £65000/annum (plus excellent company benefits)
locally) c£55,000 to £65,000 per year Pension, Bonuses, Training and Development, etc. Skills and Experience: Expertise in C#, .NET Core, REST API design and backend architecture. Strong SQL skills with the ability to create performant, reliable database logic. Strong understanding of ORM patterns, data mapping … product and offshore teams. Experience integrating services into CI/CD pipelines (GitHub Actions or Azure DevOps). Familiarity with clean architecture, domain-driven design, or similar engineering patterns. Understanding of containerisation workflows (Docker) and AKS operational concepts. Mentoring experience or leadership within engineering teams. Exposure to API ...

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 ...

Lead Developer

Hiring Organisation
Oscar Associates (UK) Limited
Location
Warrington, Cheshire, North West, United Kingdom
Employment Type
Permanent, Work From Home
Salary
£80,000
manual test strategies Documenting architectural decisions (ADRs) and maintaining clear technical communication Tech Stack & Experience Core technologies: .NET 10/ASP.NET Core Web API Entity Framework Core with Azure SQL .NET MAUI (offline-first mobile design) Microsoft Azure (App Services, Azure SQL, Blob Storage, Key Vault, Application Insights … years working within fast-paced, 'fail-fast' delivery environments At least 2 years in a leadership position Strong expertise in modern .NET and API design Proven Angular experience (v15+) Hands-on Azure architecture and deployment experience Experience implementing Infrastructure as Code (Bicep preferred) Experience integrating Azure Entra ...

Staff Software Engineer

Hiring Organisation
Classic Football Company Ltd
Location
Manchester Area, United Kingdom
collaborative Agile environment. You will take ownership of complex Magento and front-end initiatives, influence technical direction, and work closely with Product, Design, and Operations to ensure our platforms remain scalable, secure, and high-performing. Location: Hybrid/Remote flexibility Hours: The role is a full-time position … Responsibilities: Lead the design, development, and maintenance of Magento 2 (PHP) features, modules, and integrations, including REST and GraphQL APIs. Drive front-end development using React (JavaScript/TypeScript), consuming Magento GraphQL endpoints to deliver high-quality customer experiences. Own technical solutions from concept through to production, ensuring quality ...

.NET Developer

Hiring Organisation
SYSTEM C HEALTHCARE LIMITED
Location
Liverpool, Merseyside, North West, United Kingdom
Employment Type
Permanent
Salary
£35,000
squad, youll translate user needs into well-designed, well-tested services and APIs, collaborating closely with Product, QA, DevOps and DBAs. What youll do Design, develop and unit-test new features; improve and support existing modules Build and version RESTful APIs using C#/.NET with strong dependency injection …/CD pipelines and test automation with Azure DevOps/TeamCity/Octopus What youll bring Commercial experience in C# .NET and SQL, with API design and versioning know-how Familiarity with REST, dependency injection, JSON and git-based workflows Exposure to Azure (App Services, Functions, Service ...

Full Stack Web Developer

Hiring Organisation
LM RECRUITMENT SOLUTIONS LTD
Location
Stroud, Gloucestershire, South West, United Kingdom
Employment Type
Permanent, Work From Home
Salary
£55,000
full-stack technologies. Develop new features and functionality for both front-end and back-end components in following best practices. Implement and maintain robust API integrations with internal and third-party systems. Assist in monitoring, troubleshooting, and resolving production issues to maintain system reliability and data integrity. Participate … reviews, testing, and documentation to maintain high standards of code quality. Required Skills & Experience Strong full-stack development experience with Laravel/PHP for API development and front-end frameworks such as Vue.js (or similar). Familiarity with Node.js for working on an existing LoopBack application. Experience with ...

Technical Team Lead - eDV Cleared

Hiring Organisation
Forward Role
Location
Cheltenham, Gloucestershire, South West, United Kingdom
Employment Type
Permanent
identify risks, plan deliveries, and support resource allocation Core Focus: Architecture & Integration Cross-domain strategy and secure system integration Java/Spring Boot microservices design and governance Senior technical stakeholder liaison across customer and internal teams What You Bring: Proven experience leading teams in Agile, customer-facing software projects … Experience with one or more of the following: Full-stack web development Software as a Service (SaaS) Mobile application development API design and development Cloud platforms (AWS, Azure, GCP) Front-end development and user experience (UX) Clearance required - Due to the nature of the clients' work ...

Backend Engineer - Build Scalable, High‐Impact Financial Infrastructure

Hiring Organisation
Albert Bow
Location
London, UK
Employment Type
Full-time
+ 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 ...

Back End Developer

Hiring Organisation
Osdire
Location
Liverpool, England, United Kingdom
designing and building robust, secure, and high-performance backend systems that support core marketplace functionality and evolving business requirements. Key ResponsibilitiesSystem Architecture & Development Design and implement scalable, maintainable backend architecture Apply SOLID principles, clean code practices, and clear separation of concerns Develop modular components using service-layer and repository … Passport) Service listings (creation, editing, search, filtering) Order lifecycle and transaction management Secure payment integrations (Stripe, PayPal) Internal messaging, reviews, and dispute resolution RESTful API development with versioning support Database & Performance Design and maintain efficient, well-structured database schemas Optimise SQL queries, indexing, and prevent N+1 issues Implement ...

Software Developer

Hiring Organisation
Reed
Location
Wellington, Somerset, England, United Kingdom
Employment Type
Full-Time
Salary
£41,000 - £51,000 per annum, Inc benefits
Type: Full-time Salary: Up to £51,000 Join our clients innovative Research & Development team as a Full-Stack Developer, where you will design, build, and maintain applications using Angular on the frontend and .NET (C#) on the backend. This role involves close collaboration with the Product and Testing … C#), asynchronous programming, and dependency injection. Quality-focused with experience in unit testing (Jest/NUnit or similar) and code review. Knowledge of RESTful API design, OpenAPI/Swagger, and NoSQL databases. Excellent collaboration skills, with experience working closely with product teams, platform teams, developers, and testers. Strong ...

Mid-Senior Ruby on Rails Engineer (B2B SaaS | Hybrid | UK)

Hiring Organisation
Transreport
Location
London Area, United Kingdom
architecture Extensive experience with PostgreSQL, including performance tuning and complex queries. Experience with background job processing using Sidekiq and Redis. Solid understanding of RESTful API design, JSON serialization, and authentication (e.g., JWT, SSO). Hands-on experience with AWS services and containerised deployments (Docker). Experience troubleshooting ...

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 ...

Senior Data Engineer (Contract) - Azure

Hiring Organisation
Profiles Creative
Location
City of London, London, United Kingdom
Hybrid Experience needed: Azure stack - Blob Storage, SQL Database, ADF, Synapse Analytics, and Azure Functions. Delivered end-to-end DWH (source integration, dimensional models, API layer) as a lead engineer. Designed and built Bronze/Silver/Gold medallion architecture in Azure. Made architectural decisions (source integration patterns, APIdesign, dimensional models) and created ADRs. Dimensional modelling (Kimball star schemas), SCD Type 2, MDM (entity resolution, golden records). Batch + incremental ETL/ELT pipelines. File-based integration (CSV/XLS ingestion, error handling). Database replication (SQL Server snapshot/delta strategies). Partitioning strategies (date ...

Senior Java Application Engineer

Hiring Organisation
Robert Walters
Location
Manchester, Lancashire, United Kingdom
Employment Type
Permanent
Salary
GBP Annual
innovation, and low-cost investing, fosters an inclusive and collaborative culture that empowers employees to make a meaningful impact globally. What you'll do * Design and build scalable Spring Boot microservices that power critical business applications * Create robust units, Cucumber, and Playwright tests, championing automation and quality engineering * Architect … deploy, and maintain AWS infrastructure using CloudFormation * Lead system analysis, application and database design, and seamless third-party integrations * Turn complex technical requirements into clean, maintainable, production-ready code * Manage code promotion across development, test, and production environments, including change control and production support * Collaborate closely with cross-functional ...

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 ...