Senior Developer (C#, ASP.NET MVC, JavaScript)

System C; Belfast; Hybrid; GBP 50,000 - 70,000; Full time

Job summary

System C is looking for a Senior Developer to enhance their CIS Oncology product suite, known as ChemoCare, which is vital for managing chemotherapy treatments across the NHS. The role involves designing, developing, and maintaining software, while ensuring quality and reliability.

The ideal candidate will have strong experience with C#, ASP.NET MVC, and SQL Server, bringing both back-end and front-end skills. Join System C to contribute to meaningful projects that support improved care outcomes across the NHS.

Qualifications

• Strong professional experience with C# and ASP.NET MVC.
• Strong SQL Server experience.
• Experience developing for the web with JavaScript, HTML, CSS.
• Experience using GitHub for source control.

Responsibilities

• Designing, developing, and maintaining software within the CIS Oncology product suite.
• Owning complex features through design, implementation, and testing.
• Contributing to the technical direction of the ChemoCare product suite.
• Reviewing code written by others and providing constructive feedback.

Skills

C#

ASP.NET MVC

SQL Server

JavaScript

HTML

CSS

GitHub

React Native

TypeScript

Job description

Description

At System C, we create technology that connects care and improves outcomes across the NHS. Our CIS Oncology (ChemoCare) product plays a critical role in supporting chemotherapy treatment management nationwide, and we are continuing to invest in its safety, quality, and long-term evolution.

The Senior Developer role sits within the CIS Oncology product suite (ChemoCare), which supports the management of chemotherapy treatment across the NHS. ChemoCare is a market leading product in its field, with a forward looking programme of work to ensure it continues to provide safe, effective, and valued support to NHS customers.

This is a senior individual contributor role, intended for an experienced developer who enjoys hands on work. The role supports reliable delivery, good engineering practice, and ownership of more complex areas of the product.

What You Will Do

• Designing, developing, and maintaining software within the CIS Oncology (ChemoCare) product suite
• Owning complex features or technical areas through design, implementation, and handover into testing and release
• Making technical decisions and escalating risks or trade‑offs where needed.
• Contributing to the technical direction of the ChemoCare product suite, balancing near term delivery with longer term maintainability
• Working closely with the QA team to support effective testing, defect resolution, and overall product quality
• Ensuring code is clear, maintainable, and appropriately tested, in line with agreed development standards
• Reviewing code written by others and providing practical, constructive feedback
• Supporting and mentoring less experienced developers as part of normal team working
• Providing 3rd line support (as part of a shared team responsibility) for the ChemoCare product, including investigation and resolution of complex defects where required

What You Will Bring

• Strong professional experience with C# and ASP.NET MVC
• Strong SQL Server experience
• Experience in developing with for the web: JavaScript, HTML, CSS
• Knowledge of principles of writing mobile apps and deployment on apple and android app stores
• Experience using GitHub for source control and collaboration
• Strong analytical and problem‑solving skills both at a strategic and tactical level
• Experience working with complex or long‑lived codebases
• Confidence contributing to technical design and making informed trade‑offs
• A pragmatic, calm approach when dealing with ambiguity or pressure
• Clear communication, including explaining technical constraints to non‑technical stakeholders
• Significant commercial experience operating at senior developer level in both back‑end and front‑end areas

Nice to have

• Experience with React Native or React, or equivalent frameworks
• Experience in writing automated unit tests using NUNIT
• Good understanding of waterfall, agile and scrum development methodologies, and their practical application.
• Experience in .NET 10 and other latest technologies including AI integration
• Experience in TypeScript

Why join System C?

You will work on software that genuinely matters, alongside people who value collaboration, ownership, and integrity. We support flexible working, encourage reflective practice, and value those who are comfortable navigating change while keeping quality and patient safety at the forefront.

Apply today and help us continue to deliver technology that supports better care across the NHS.