Senior Developer

As a Senior Developer at Commercial, you will play a key role in supporting, maintaining, and evolving our core business systems and integrations. Working within the Business Systems team, you will deliver reliable, scalable solutions that support day-to-day operations, improve user experience, and enable business growth. This is a hands-on, varied role combining development, database optimisation, and systems integration. You will collaborate closely with stakeholders across the business, contributing to both new initiatives and continuous improvement of existing platforms. Your responsibilities as a Senior Developer will be: Develop, maintain, and enhance business applications, integrations, and internal systems, ensuring solutions are scalable, reliable, and user-focused. Work closely with stakeholders to understand requirements, provide technical guidance, and deliver pragmatic solutions aligned to business needs. Support and improve existing systems by troubleshooting issues, optimising performance, and enhancing usability and stability. Design and deliver system integrations (APIs, middleware, data exchange), ensuring robustness, security, and effective data flow between platforms. Take ownership of database performance, including schema design, query optimisation, indexing strategies, and data integrity. Manage and support data processes such as imports, exports, transformation, and reconciliation across multiple systems. Contribute across the full development lifecycle, including design, development, testing, deployment, and ongoing support. Support release management, version control, and deployment processes to ensure controlled and stable system changes. Collaborate with internal teams and third-party suppliers to ensure systems and integrations operate effectively. Contribute to continuous improvement by modernising legacy systems and adopting best practice development approaches. Explore and implement opportunities to leverage AI and automation technologies to improve system efficiency, data usage and business processes, ensuring solutions are practical, secure and aligned with business needs. About you: You will have strong experience in software development using Microsoft technologies (C#, .NET, SQL Server). Solid understanding of the full development lifecycle, including support and continuous improvement. Proven expertise in SQL Server, including performance tuning, database design, and query optimisation. Experience with integrations, APIs, middleware (e.g. Connex or similar), and data flows (ETL, transformation, mapping). Ability to troubleshoot complex system and data issues across interconnected platforms. Good understanding of development best practices, including source control, testing, and structured troubleshooting. Exposure to business systems (ERP/CRM), cloud platforms, or web technologies is beneficial. Strong problem-solving mindset with a focus on improving systems and user experience. Well organised, able to manage priorities in a fast-paced environment. Confident communicator who works collaboratively and contributes positively to team culture. Awareness or interest in AI, automation or emerging technologies, with a practical approach to applying them to real business challenges. About us We’re Commercial – a purpose-driven, people-first organisation that’s on an exciting journey to reach a £100m annual turnover and beyond. But what really defines us isn’t just the numbers – it’s the people, the culture we’ve built, and the innovative spirit that drives us forward. As Business Transformation Specialists, we combine original thinking with practical expertise to improve the everyday experiences and outcomes for our clients. Our areas of specialism include Managed IT, Smart Technologies, Digital Workspace, Interiors, Office Supplies, PPE, Facilities, and Workwear. We’re proud to be an award‑winning employer, having won our category at the Sunday Times Best Places to Work 2026 , recognised as the Best Place to Work in the Business and Management Services industry. In August 2025, we proudly achieved Ecovadis Platinum status, placing us among the top 1% of companies assessed worldwide for sustainability. We’re #commercialbynature – a team driven by values, sustainability, and continuous improvement. And now is a particularly exciting time to join us. Our Commercial HQ is undergoing a full refurbishment – and you’ll be working in a brand new, state-of-the-art office space, purposefully designed to support creativity, collaboration, and wellbeing. Our Benefits We believe that people thrive when they feel truly valued and at Commercial, we make sure that happens every single day. When you join us, you’ll enjoy a desirable benefits package designed to support your personal and professional wellbeing, reward your hard work, and help you flourish in all areas of life. Here’s what you can look forward to: A base salary of up to £65,000 per annum Hybrid working structure with the flexibility to work from home for part of the week A generous holiday allowance of 25 days plus bank holidays, which increases with length of service An enhanced family leave package to support you and your growing family Life Assurance, offering peace of mind with cover equivalent to four times your salary Access to health & wellbeing support – including 24/7 GP access, physiotherapy, and a confidential Employee Assistance Programme Free mortgage advice from leading broker Charles Cameron & Associates, available to you, your family, and friends Inclusive employee networking groups, with dedicated menopause and neurodiversity champions The Comm-Unity - employee representatives from across the business who give team members a voice and share ideas and feedback with the board each quarter Feel-good extras – including volunteering days, onsite parking at all four of our offices, free refreshments, an employee community platform to stay connected to like-minded colleagues, weekly company-wide Learning Days – a chance to share ideas, gain fresh insights, and explore a wide range of topics together, cycle-to-work and EV schemes, flexible working options, and much more! Training and Development At Commercial, we invest in our people, 86% of our Senior Managers and 80% of our Directors have been promoted within. Whether you're just starting out or looking to grow, your development journey is as unique as you are – and we’ll support you every step of the way by offering training and development opportunities for career growth. Diversity & Inclusion At Commercial, we believe our differences make us stronger. We are committed to creating a workplace where everyone feels seen, heard, and valued – no matter your background, belief, identity, or way of life. We’re proud to stand beside one another through life’s ups, downs, and everything in between. Our Diversity & Inclusion initiatives – including support around menopause, neurodiversity, mental health, and more – are just one of the ways we look out for each other and celebrate what makes us unique. We hire people, not checklists. So even if you don’t tick every box in the job description, we’d still love to hear from you. Your potential, passion and perspective might be exactly what we’re looking for! We are an equal opportunity employer and welcome applications from all individuals, regardless of race, ethnicity, gender identity, age, religion, disability, sexual orientation, or socio-economic background. To learn more about who we are, our values, and how we protect your personal data during the recruitment process, please visit our website and review our Job Applicant Privacy Policy https://commercial.co.uk/careers .