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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Developer (JavaScript, ASP.NET MVC) - **Company:** 慨正橡扯 - **Location:** Belfast, UK - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** HTML, JavaScript (Programming Language), .NET Framework, Agile Methodology, Android Software Development, Application Integration Architecture, ASP.NET MVC Framework, Unit Testing, C Sharp (Programming Language), Cascading Style Sheets (CSS), Github, Nunit, Scrum Methodology, Software Maintenance, SystemC, TypeScript, ReactJS, Backend, React Native, Software Version Control, GXP - **Published:** September 8, 2026 - **Apply:** https://www.collegerecruiter.com/job/2840615303-senior-developer-javascript-aspnet-mvc ## About the Role 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., * 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, * 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. ## Description * 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 ## Related Videos - [Blueprints for Success: Steering a Global Data & AI Architecture](https://www.wearedevelopers.com/videos/1577-blueprints-for-success-steering-a-global-data-ai-architecture) - [The Resilience of the World Wide Web](https://www.wearedevelopers.com/videos/1281-the-resilience-of-the-world-wide-web) - [Navigating the Corporate Jungle: Life as a Developer in a large Company](https://www.wearedevelopers.com/videos/621-navigating-the-corporate-jungle-life-as-a-developer-in-a-large-company) - [Agile work at CARIAD – Creating a customer web application for controlling the vehicle ](https://www.wearedevelopers.com/videos/200-agile-work-at-cariad-creating-a-customer-web-application-for-controlling-the-vehicle) - [NoLoJS - Avoiding JavaScript Cruft with HTML and CSS - Aaron T. Grogg](https://www.wearedevelopers.com/videos/1806-nolojs-avoiding-javascript-cruft-with-html-and-css-aaron-t-grogg) - [WeAreDevelopers LIVE - Streaming HTML](https://www.wearedevelopers.com/videos/2135-wearedevelopers-live-streaming-html) ## Related Articles - [What’s the Difference between a Junior, Mid, and Senior Developer?](https://www.wearedevelopers.com/magazine/238-what-s-the-difference-between-a-junior-mid-and-senior-developer) - [Frontend Developer Salary in The UK](https://www.wearedevelopers.com/magazine/233-frontend-developer-salary-in-the-uk) - [Dev Digest 120 - Apple and peers](https://www.wearedevelopers.com/magazine/455-dev-digest-120-apple-and-peers) - [React Developer Salary [2023]](https://www.wearedevelopers.com/magazine/198-react-developer-salary-2023) - [Fullstack Developer Salary UK](https://www.wearedevelopers.com/magazine/251-fullstack-developer-salary-uk) - [Dev Digest 121 - AI goes offline](https://www.wearedevelopers.com/magazine/456-dev-digest-121-ai-goes-offline)