Senior Full Stack Product Engineer

At Marsello, we're building the Loyalty Marketing Platform that helps retailers and hospitality brands grow loyal customers wherever they are. More than 2,000 brands around the world use Marsello to deliver personalised marketing, loyalty and customer engagement experiences that drive measurable results. We're looking for two Senior Full Stack Product Engineers to help shape the future of our platform and the way we build software. This is a senior technical leadership role where you'll own significant areas of the product end-to-end, influence architecture and infrastructure decisions, and help define how our engineering team works in an AI-first world. How we work Marsello's engineering team operates using an agentic engineering model. Every engineer uses AI agents as part of their daily workflow. Success here isn't measured by how much code you personally write. It's measured by how effectively you can define problems, orchestrate agents, review outputs, and help the team continuously improve the way we build software. We're looking for engineers who are excited by the opportunity to combine strong technical judgement with modern AI-assisted development practices. What you'll do You'll lead the delivery of complex product initiatives while helping raise the technical capability of the wider team. You'll: Own technical direction for major areas of the platform Contribute to architecture, infrastructure and engineering strategy, along with others in the engineering team. Design and deliver features across our .NET, MongoDB, React and AWS stack Use AI coding agents to run multiple workstreams in parallel and accelerate delivery Review, refine and validate agent-generated code to ensure quality, reliability and maintainability Improve the way we build software through better prompts, evals, tooling and development practices Take part in our engineering support rotation and help solve complex customer issues Mentor intermediate and junior engineers through pairing, coaching and technical guidance Contribute to infrastructure, observability and platform improvements across our AWS environment What we're looking for Strong software development experience in a SaaS environment Strong experience building and owning systems end-to-end Deep expertise with C#, .NET, Web APIs, MongoDB and React/TypeScript Hands-on experience with AWS and confidence working with Terraform Solid understanding of CI/CD, observability and operating production systems Experience using AI-assisted development tools and workflows in a meaningful way Strong architectural and problem-solving skills Excellent communication skills and the ability to work effectively across engineering, product and customer-facing teams A collaborative mindset and a genuine desire to help others grow Why Marsello? You'll join a high-performing, globally distributed team with a strong culture, meaningful product challenges, and the opportunity to help define what modern AI-enabled software engineering looks like in practice. We're open to candidates based anywhere in New Zealand. Wellington is preferred, but not required, as we find occasional face-to-face collaboration valuable for a role that works closely across teams and disciplines. If you're excited by building great software, solving complex technical problems, and helping shape the future of AI-assisted engineering, we'd love to hear from you. Applications are open until 12 July 2026 . We encourage interested candidates to apply as soon as possible, as we will be reviewing applications as they are received and may close the process earlier if we find the right person for the role.