Senior Umbraco .NET Developer

Onyx-Conseil; Spalding; Hybrid; GBP 45,000 - 55,000; Full time

Benefits offered by this job

Holiday

Pension

Job summary

Onyx-Conseil in Spalding, UK, is seeking a Senior Umbraco .NET Developer to own full‑stack projects, influence technical decisions, and deliver modern web applications using C#, .NET Core and Umbraco CMS.

The role includes work on greenfield and existing systems, designing REST APIs, integrating third‑party services, mentoring peers, and helping define development standards for enterprise CMS solutions in a hybrid setup (three days on-site).

Qualifications

• Strong commercial experience with Umbraco CMS development.
• Proven background with C#, .NET / .NET Core and ASP.NET Core.
• Full-stack development experience including HTML, CSS/SCSS and JavaScript.
• Experience with SQL Server, Entity Framework and API integrations.
• Ability to troubleshoot complex technical issues and deliver scalable solutions.
• Desirable experience with Azure, Azure DevOps, CI/CD or modern JavaScript frameworks.

Responsibilities

• Develop and maintain web applications using C#, .NET Core and ASP.NET Core.
• Build and enhance websites and platforms using Umbraco CMS.
• Design and integrate REST APIs and third-party systems.
• Contribute to architecture, technical design and development standards.
• Support, modernise and optimise existing applications and platforms.
• Mentor and provide technical guidance to other developers.

Skills

Umbraco CMS

C#

ASP.NET Core

Full-stack

HTML CSS JS

SQL Server

Azure DevOps

Tools

Azure DevOps

Git

Job description

Senior Umbraco .NET Developer
Spalding, Lincolnshire - Hybrid, 3 days on-site
£45,000 - £55,000 + Holiday + PensionAre you an experienced Umbraco/.NET Developer looking for a senior position where you can take ownership of full-stack development projects, influence technical decisions, and work on the design and delivery of modern web applications using the latest Microsoft technologies?This is an excellent opportunity to join a growing technology business specialising in digital transformation, bespoke software development and enterprise applications. You'll play a key role in delivering high-quality web platforms and CMS-driven solutions for a diverse client base while helping to shape development standards and best practices across the team.In this hands-on position, you'll work across both new and existing applications, developing functionality using C#, .NET and Umbraco CMS, integrating third-party systems and APIs, and contributing to the ongoing enhancement and modernisation of business-critical solutions. You'll be involved throughout the full software development lifecycle, from technical design through to deployment and support.The ideal candidate will have strong commercial experience with Umbraco development and the Microsoft .NET stack, alongside excellent problem-solving abilities and a passion for delivering high-quality, maintainable software. This role offers the opportunity to work on technically varied projects while developing your leadership and architectural expertise.

The Role:

• Develop and maintain web applications using C#, .NET and ASP.NET Core
• Build and enhance sophisticated websites and digital platforms using Umbraco CMS
• Design and integrate REST APIs and third-party business systems
• Contribute to architecture, technical design and development standards
• Support, modernise and optimise existing applications and platforms
• Mentor and provide technical guidance to other developers

The Person:

• Strong commercial experience with Umbraco CMS development
• Proven background with C#, .NET / .NET Core and ASP.NET Core
• Full-stack development experience including HTML, CSS/SCSS and JavaScript
• Experience with SQL Server, Entity Framework and API integrations
• Ability to troubleshoot complex technical issues and deliver scalable solutions
• Desirable experience with Azure, Azure DevOps, CI/CD or modern JavaScript frameworks

Reference Number: BBBH278148

We are an equal opportunities company and welcome applications from all suitable candidates.