Spherecast

Senior Backend Engineer (Visa Sponsorship)

San Francisco | OnSite

Senior Backend Engineer (Visa Sponsorship) San Francisco | OnSite SENIOR BACKEND ENGINEER (VISA SPONSORSHIP) As a Backend Engineer at Spherecast, you will be responsible for building the backbone to scale Agnes throughout the world - our AI Supply Chain Manager that decides what to produce, where to make it, and how to move it through factories, warehouses, and channels. This is a fast-paced, highly autonomous role for someone who can own backend systems end-to-end: from designing data architectures to making sure user requests get processed in real time, so physical goods can flow reliably to the right place, at the right time. You'll work directly with the core team to turn the physical flow of goods into something as programmable as code. If you're a builder who thrives at the intersection of large-scale data architectures, systems engineering, and organizing messy real-world data, this is your opportunity to shape how global brands run their supply chains. WHAT WE'RE LOOKING FOR You are a great fit if you have: - Hands-on experience with modern backend stack environments: FastAPI, Python, and testing frameworks such as pytest, with a track record of shipping real products. - Claude Code, Codex, and OpenCode are your best friends - you know how to parallelize instances to make sure we're shipping 24/7, even while you sleep, and you know the ins and outs of each of them at any time. - A track record of building full-stack apps, including designing data architectures and backend systems. - Proficiency in