Senior Developer in Belfast

We are looking for an experienced and versatile Senior Developer to join our growing engineering team. You will play a central role in the design, development, and delivery of complex software solutions across our technology stack. As a senior member of the team, you will be expected to take ownership of solution design, contribute to architectural decisions, and provide technical leadership to peers.

WHAT WILL YOU BE DOING?

• Solution Design & Architecture
  • Demonstrable experience leading end-to-end solution design, from initial requirements through to delivery and testing.
  • Ability to produce clear technical documentation including architecture diagrams, design specs, and decision records.
  • Strong understanding of system architecture principles and the ability to evaluate trade-offs across different approaches.
  • Experience taking overall ownership of solutions - including infrastructure context, integration points, and testing strategies.
• Backend Languages
  • Excellent programming skills with proven experience building production-grade applications, in Python, Typescript and Go are desirable.
  • Familiarity with Python frameworks (FastApi, Django), packaging, testing (e.g. pytest), and best practices for maintainable, scalable code.
  • Or alternatively express/Hono or other backend frameworks.
• Front-End Development
  • Solid front-end development skills, with hands-on experience in modern JavaScript and TypeScript.
  • Experience working with React or similar component-based frameworks to build responsive, user-friendly interfaces.
• REST APIs & OAuth
  • Strong experience designing and consuming RESTful APIs.
  • Working knowledge of OAuth 2.0 and modern authentication/authorisation patterns.
• Database Knowledge
  • Proficiency with relational databases, specifically PostgreSQL and MySQL.
  • Comfortable writing complex queries, managing schema design, and optimising database performance.
• Technology Stack
  • Candidates should be familiar with, or enthusiastic to work across, our core suite of languages and frameworks: Python - primary backend language, JavaScript & TypeScript - front-end and scripting, React - front-end UI framework, Go - performance-critical services, Rust - systems-level development.
  • Candidates must also be familiar with Cloud Hosting and Storage: Microsoft Azure, Amazon - cloud infrastructure, services, and deployment pipelines.
• Desirable Skills
  • The following skills are not essential but would be considered a strong advantage: Microsoft Azure - cloud infrastructure, services, and deployment pipelines, Linux & Virtualisation - administration, scripting, and virtualised environments, Dynamics 365 - integration experience with Microsoft Dynamics 365 for CRM or operational workflows.

WHAT WILL YOU BRING?

• A minimum of 5 years of professional experience in a software development role, with demonstrable time spent at a senior level.
• A track record of delivering complex, multi-component software projects end to end.
• Experience mentoring or guiding less experienced developers is desirable.

IS FIBRUS FOR ME?

At Fibrus Limited, we put our people first! Having been awarded the Investors in People 'We invest in People' standard accreditation, we are proud to be a company who encourage colleagues to do and be their very best. Our culture is focused on trust, collaboration, growth, and flexibility. We invest in our people, offering colleagues benefits that improve their personal lives as well as their careers! So along with competitive salaries and an excellent benefits package, we also offer our colleagues benefits including mental health workshops, professional development support and private healthcare. We also recognise the importance of supporting our colleagues with life changes and have comprehensive policies around menopause, mental health, pregnancy loss and leave for maternity, parental and adoption. As we continue to grow, you would be joining a team of dedicated and passionate people who work super hard every day to improve the lives of those in our own communities by transforming the digital infrastructure of Northern Ireland and Great Britain! We're building something special at Fibrus, with our team at the very heart of it and we are excited to speak to potential colleagues who share our purpose!

HOW TO APPLY

To apply to join the Fibrus Group, please do so online and our recruitment team will be in contact with you once we've had a chance to have a look at your application. We wish you the best of luck and thank you for your interest in Fibrus.

Fibrus Limited, Fibrus ISP, Hyperfast and Viberoptix, belong to the Infracapital group of companies. We will retain your information, for the purposes of recruitment, for a period of up to 12 months. We may also share your information with our partner organisations for the purposes of recruitment. Please email if you do not wish us to retain your information or do not wish for us to share your information.

To be considered for this role you will be redirected to and must complete the application process on our careers page. To start the process click the Continue to Application or Login/Register to apply button below.