Senior .NET Software Engineer – Azure & APIs

Kensington Mortgage Company; Marlow, Greater London; Hybrid; GBP 65,000 - 90,000; Full time

Job summary

Kensington Mortgage Company seeks a Software Engineer to design, build and maintain secure, scalable digital solutions across back-end and API layers. You will work with C#, .NET and Azure, contributing to both new capabilities and modernisation of existing applications.

You’ll collaborate with engineers, architects, QA, product owners and analysts through full delivery, while practicing secure coding, automated testing and CI/CD in an Agile environment.

Qualifications

• Five or more years of commercial software development and support for production systems.
• Experience delivering software within a UK-regulated environment, ideally financial services.
• Strong C# and .NET experience including ASP.NET Core.
• Experience designing and consuming REST APIs; OpenAPI knowledge.
• Azure cloud experience (PaaS and serverless).
• SQL and data modelling skills.
• Git, PRs and automated CI/CD pipelines (preferably Azure DevOps).
• Automated testing across applications and integrations.
• Logging/telemetry with Application Insights.
• Secure software development, including authentication and secrets management.
• Familiar with automated code quality and security tooling (Wiz, SonarQube Cloud, Snyk).
• Working in an Agile delivery environment.

Responsibilities

• Design, develop and maintain web applications, APIs and integration services.
• Build solutions using C#, .NET, ASP.NET Core and Azure.
• Develop and maintain automated unit, integration and API tests.
• Contribute to technical design, backlog refinement and demos.
• Participate in peer code and design reviews.
• Support automated build and deployment pipelines with quality and security checks.
• Apply secure-by-design practices and remediate vulnerabilities.
• Use logging/telemetry to monitor production apps.
• Investigate incidents and conduct root-cause analysis.
• Refactor and reduce technical debt while improving existing apps.
• Collaborate across technical teams and delivery partners.

Skills

C# / .NET

SOLID principles

REST APIs

OpenAPI

Microsoft Azure

SQL / data modelling

Git / CI/CD

Automated testing

Logging / telemetry

Secure SDLC

Security tooling (Wiz / SonarQube / Sn

Tools

Azure DevOps

Application Insights

Wiz

SonarQube Cloud

Snyk

Job description

Kensington Mortgage Company seeks a Software Engineer to design, build and maintain secure, scalable digital solutions across back-end and API layers. You will work with C#, .NET and Azure, contributing to both new capabilities and modernisation of existing applications.

You’ll collaborate with engineers, architects, QA, product owners and analysts through full delivery, while practicing secure coding, automated testing and CI/CD in an Agile environment.