About Mutinex We're an early-stage B2B SaaS startup with a proven platform, big-name clients, and millions in revenue. We're not chasing unicorn status; we're building a sustainable, long-lasting business (think Bowhead Whale!). Mutinex helps marketers understand their ROI and make smarter decisions with their budget. We're a hybrid team based in Sydney, Melbourne, and New York. We value communication, open-mindedness, and a culture of feedback. All staff receive equity (ESOP), and we offer increasing annual leave based on tenure. The Role As a Senior Software Engineer on the DataOS team, you'll be a key technical contributor, responsible for building and scaling DataOS , our core platform for automating data ingestion and processing for Marketing Mix Modelling (MMM). While your primary focus is building robust and scalable data systems, this role is full-stack in nature. You'll have the opportunity to work across our entire technology stack, contributing to our frontend applications to deliver complete, end-to-end features for our users. You'll apply first-principles software engineering to complex data challenges, taking ownership of a high-impact domain within a fast-growing, product-led startup. Role Responsibilities Platform Architecture and Development: Be a key player in steering the technical design and development of DataOS. You'll architect and build new features, evolve the platform's architecture for scalability and maintainability, and uphold the highest standards of code quality. Building Scalable Data Systems: Play a crucial part in the engineering efforts to scale our data processing and warehousing solutions. This involves performance engineering, optimizing distributed systems, and designing infrastructure that can handle terabytes of data efficiently. End-to-End Feature Delivery: Take ownership of features from the data processing layer all the way to the user interface. You'll work on both the backend APIs and the frontend components that consume them, ensuring a seamless user experience. Automated Data Quality & Observability: Go beyond simple data validation. Design and implement robust, automated frameworks for data quality assurance, error handling, and end-to-end observability across our data platform. Performance Optimization: Proactively identify and eliminate performance bottlenecks across the platform, from data ingestion and transformation to storage and retrieval. Collaboration and Mentorship: Work within a cross-functional team of product managers, data scientists, and other engineers. Share your expertise with team members, championing best practices through code reviews and technical guidance. What We're Looking For Strong Software Engineering Foundation: You have experience building and maintaining production-grade backend systems and services. You live and breathe software engineering principles like SOLID, design patterns, and building testable, maintainable code. Your experience is in software, applied to the data domain. Experience Building Data-Intensive Applications: You have a proven track record of designing, building, and scaling complex, data-intensive systems in the cloud. You understand the unique challenges of distributed systems, concurrency, and handling large data volumes. Full-Stack Flexibility: You have experience with, or a strong willingness to work on, modern frontend frameworks (we use React). You understand that delivering a great data product means building the user experience that makes it accessible and useful, and you aren't afraid to get your hands dirty in the UI. Modern Tech Stack: You have hands-on experience with modern cloud infrastructure (we use GCP) and infrastructure-as-code (e.g., Pulumi, Terraform). While experience with data orchestrators (e.g., Dagster, Airflow) or transformation tools (e.g., dbt) is valuable, your core strength is in a general-purpose language like Python or Go. A Passion for the Craft: You see software engineering as a craft and take pride in your work. This translates into a commitment to building high-quality, reliable, and well-tested software. You don't just write code that works; you write code that is clean, maintainable, and a pleasure for others to work with. Growth Mindset: You're eager to learn, take on new challenges, and continue to deepen your technical expertise and impact. Excellent Communicator: You can clearly articulate complex technical ideas to both technical and non-technical stakeholders. Proactive Problem-Solver: You don't just fix bugs; you identify the root cause and improve the system to prevent future issues. Ready to join us? If you're passionate about building data platforms and eager to make a big impact in a fast-growing startup, we'd love to hear from you. Send us your resume and a brief cover letter explaining why you're excited about this opportunity.