Software Engineer (Mobile & Sensing)

About the Company Cartesian is building spatial intelligence for indoor environments to drive operational efficiency. We’re tackling one of the biggest challenges in the $35T global retail industry: in-store inventory visibility. Our platform delivers accurate indoor positioning and actionable product location insights, helping retailers streamline operations, optimize workflows, and reduce inefficiencies. Leveraging wireless signals, we provide a uniquely scalable, infrastructure-free solution already deployed by international fashion brands. Founded by an MIT engineering professor and alum behind the award-winning, patented core technologies, Cartesian spun out in 2023. Originally backed by the prestigious SBIR Award from the US National Science Foundation, we've bootstrapped to a live product that's now deployed in over a dozen countries and have been aggressively scaling in the market. About the Role Our first product is the only indoor inventory positioning system that operates on existing handheld devices. Mobile provides the critical interface between users and our system: you will build both SDKs and end-user apps that collect high rates of data from on-devices and peripheral sensors, provide real-time feedback and help users spatially locate items in stores. We’re actively adding new customers and expanding our product portfolio, so our work spans the full lifecyc [... source excerpt omitted ...] iving deep into why things work a certain way (e.g. the data from this output doesn’t look correct), focusing on simplicity, and building seamless interactions for users. Minimum Requirements We are looking for slope, not experience. That said, this is not an entry level position and to be competitive, we expect 2+ years of experience building mobile products at a company with a high engineering bar. Passion for building applications in the physical world - connecting sensors, data, insights and people together via performant, intuitive interfaces. Track record of driving complex, end-to-end projects. Strong opinions on how to structure mobile applications for correctness, maint [... source excerpt omitted ...] lity, and performance. Excellent written communication (designing projects, sharing progress updates, reviewing other people’s work, getting buy-in on decisions, etc.) Preferred Qualifications Comfortable contributing to the backend when needed. Experience shipping and maintaining mobile SDKs to enterprise customers at scale. Experience defining, implementing, and automating testing on real-world hardware. Why Now We’re a fast-moving MIT startup at an important inflection point for our product growth and direction. We are building a talent-dense team of engineers and applied researchers to solve hard, high-impact problems in retail operations. You will have outsized ownership a