Sigma Consulting Group

Full-Stack Developer (Founding Engineer) Location: London, United Kingdom (Hybrid) Employment Type: Full-Time Department: Engineering Compensation: £50,000 + Equity About Zenrox Zenrox Healthcare UK is building an AI-powered marketplace that connects healthcare providers with MHRA-compliant medical equipment suppliers. Our flagship platform, ZenroxIQ, transforms procurement through intelligent supplier matching, automated compliance workflows, and predictive analytics-serving NHS trusts and private healthcare organisations across the UK. The Opportunity We are seeking a talented Full-Stack Developer to join as a Founding Engineer, playing a key role in designing, building, and scaling our marketplace platform. This is a hands on role offering end-to-end ownership across the technology stack-from crafting seamless user experiences to developing robust backend systems. You will work closely with the CTO to shape architecture, implement core features, and deliver a high-performance platform that drives efficiency in healthcare procurement. Key Responsibilities Platform Development Develop, customise, and enhance a WordPress/WooCommerce-based marketplace platform Build core features such as quote request systems, supplier matching, and order workflow management Design and implement scalable backend services supporting marketplace operations Frontend & User Experience Develop responsive, high-quality user interfaces using modern JavaScript frameworks (e.g., React) Optimise user experience across buyer and supplier journeys Ensure cross-browser compatibility and mobile responsiveness AI Integration & Innovation Integrate AI-driven capabilities such as visual search and pricing optimisation into the platform Collaborate on the implementation of intelligent features that enhance procurement decision making API & System Integration Design, develop, and maintain RESTful APIs Integrate third party services including payment gateways, compliance verification systems, and analytics tools Implement secure payment processing and escrow functionalities Performance, Security & Compliance Optimise platform performance, scalability, and reliability Apply secure coding practices and ensure compliance with GDPR and data protection standards Maintain high availability and system integrity Collaboration & Technical Strategy Work closely with the CTO on architecture, technical design, and system scalability Contribute to technical decision making, documentation, and engineering best practices Participate in agile development processes and continuous improvement initiatives Requirements Minimum of 3+ years' experience in full stack development Strong proficiency in PHP with hands on WordPress/WooCommerce development experience Solid frontend development skills using JavaScript and frameworks such as React Experience with database design and optimisation (MySQL or PostgreSQL) Strong understanding of RESTful API design and integration Knowledge of secure coding practices and data protection (GDPR) Ability to work independently, take ownership, and make pragmatic technical decisions Preferred / Advantageous Experience Experience building marketplace or e commerce platforms Hands on experience with payment gateway integrations (e.g., Stripe, PayPal) Experience developing B2B or enterprise-grade software solutions Familiarity with WooCommerce plugins (e.g., YITH or similar tools) Exposure to healthcare or regulated industries DevOps experience (e.g., AWS, Docker, CI/CD pipelines) Why Join Zenrox Founding engineering role with meaningful ownership and equity participation Opportunity to build critical infrastructure for healthcare procurement High level of autonomy to design and implement end to end solutions Direct collaboration with a visionary founding team Clear pathway to technical leadership roles as the company scales How to Apply Interested candidates should submit their: CV GitHub profile Link to a relevant project (or a brief project description) Position URL: Email Subject Line: Full-Stack Developer Application