Software Developer, API & Integrations

Arthur Recruitment; Greater London; On-site; GBP 70,000 - 100,000; Full time

Job summary

Arthur Recruitment is seeking an API & Integration Developer to lead the design, development and maintenance of modern API and integration services in a cloud-based Microsoft environment.

You will own API contracts, endpoints, authentication and error handling while building secure, scalable RESTful APIs and integrating internal apps with third‑party services. This role is hands-on and focused on architecture, cloud, API design and lifecycle management.

Qualifications

• Designing, developing and maintaining APIs and integration services using C# and .NET.
• Translating business requirements into robust integration solutions.
• Building cloud native solutions across Microsoft Azure.
• Developing secure, scalable and high performance RESTful APIs.

Responsibilities

• Designing, developing and maintaining APIs and integration services using C# and .NET
• Building cloud native solutions across Microsoft Azure
• Developing secure, scalable and high performance RESTful APIs
• Integrating internal applications with third party and external services
• Translating business and technical requirements into effective integration solutions
• Defining API contracts, endpoints, request and response structures, authentication and error handling
• Developing lightweight administrative and integration interfaces using Blazor or similar technologies
• Implementing authentication and authorisation using OAuth2, OpenID Connect and Microsoft Entra ID
• Building monitoring, logging, tracing and alerting into services
• Developing automated unit, integration and API tests
• Managing API documentation using OpenAPI / Swagger
• Supporting API versioning and lifecycle management
• Working closely with DevOps teams around CI/CD and automated deployment
• Troubleshooting integration issues across development and production environments
• Helping establish strong engineering, security and development standards

Skills

C#

.NET

Azure

RESTful APIs

OAuth2

OpenID Connect

Microsoft Entra ID

Blazor

OpenAPI/Swagger

CI/CD

Tools

CI/CD tools

Cloud services

Job description

We are working with an established organisation that is continuing to invest heavily in its technology capability and is looking to hire an API & Integration Developer.

This is a hands on engineering role with responsibility for designing, developing and maintaining modern API and integration services across a cloud based Microsoft environment.

The Role

You will be responsible for:

• Designing, developing and maintaining APIs and integration services using C# and .NET
• Building cloud native solutions across Microsoft Azure
• Developing secure, scalable and high performance RESTful APIs
• Integrating internal applications with third party and external services
• Translating business and technical requirements into effective integration solutions
• Defining API contracts, endpoints, request and response structures, authentication and error handling
• Developing lightweight administrative and integration interfaces using Blazor or similar technologies where required
• Implementing authentication and authorisation using OAuth2, OpenID Connect and Microsoft Entra ID
• Building monitoring, logging, tracing and alerting into services
• Developing automated unit, integration and API tests
• Managing API documentation using OpenAPI / Swagger
• Supporting API versioning and lifecycle management
• Working closely with DevOps teams around CI/CD and automated deployment
• Troubleshooting integration issues across development and production environments
• Helping establish strong engineering, security and development standards

Technology Environment

The core technology landscape includes:

Additional exposure to the following would be highly relevant:

You will have genuine ownership across the architecture, design, development and lifecycle management of integration services and will work closely with Product, Business Analysis, Data and Technology teams.

The business is looking for someone who enjoys being hands on, solving complex integration challenges and taking ownership of technical solutions from initial requirement through to production.

It is a strong opportunity for an experienced .NET engineer who wants to move deeper into cloud, API architecture and integration engineering while remaining close to the code.