Senior Full Stack Engineer

OnBuy is an online marketplace seeking a Senior Full Stack Engineer to build, scale, and evolve their core commerce platform. The role requires end-to-end engineering ownership, designing, building, and maintaining full-stack solutions, and owning features from concept to release.

Requirements

• Design, build, and maintain full-stack solutions across UI, APIs, and backend systems
• Translate product requirements, designs, and wireframes into scalable, production-ready systems
• Build responsive, high-performance user interfaces using modern JavaScript frameworks
• Translate UI/UX designs into clean, maintainable code
• Optimise applications for speed, scalability, and usability
• Design and develop scalable services and APIs
• Work across monolith and microservices architecture (Laravel / PHP services)
• Maintain and evolve legacy systems while building modern, scalable architecture
• Write and maintain automated tests (unit, integration, end-to-end)
• Participate in and lead code reviews to ensure high engineering standards
• Debug, troubleshoot, and resolve issues across the stack
• Optimise systems for performance, reliability, and scale
• Work with large-scale data systems (MySQL, NoSQL, search platforms)
• Identify bottlenecks and proactively improve system efficiency
• Communicate technical concepts clearly to non-technical stakeholders

Benefits

• Company Equity
• 25 days annual leave + Bank Holidays
• 1 extra day off for your Birthday
• Employee Assistance Programme
• Perks at Work benefit platform
• Opportunities for career development and progression