Backend Developer SR (AM - BE - 20260512)

We're looking for a modern, AI-empowered engineer — strong fundamentals, opinionated about good design, and experienced in both agentic development tooling and AI-enabled product features — to help build and launch a new digital purchase platform. Someone who codes fast, leads by example, and can hold their own in product conversations as easily as in technical ones. The project is for a major company modernizing how customers buy online — standing up a modern stack to run the full purchase flow online, end-to-end. We're building a brand-new back-end: a modern integration layer to multiple third-party provider APIs, the AI plumbing to power agentic features across the funnel, and an agent-facing dashboard ("Agent Co-Pilot") that lets human agents see live shoppers in real time and jump into the conversation when needed. The first AI lighthouse is a customer-facing chat assistant tied into that same plumbing — pricing, configuration, eligibility checks, hand-off to a human. This is a 3-month foundation build with a senior, hand-picked team, kicking off ASAP.