Software Engineer, Full Stack

Back to jobsSoftware Engineer, Full StackNew York, New York, United States, San Francisco, California, United StatesApplyAbout InstaLILY InstaLILY is an AI products and infrastructure company that puts execution at the frontier of enterprise AI. That work begins with Lily™, the world's first AI Forward Deployed Engineer, which learns how a business works, builds the software it needs, and goes live in days. It does not leave when the work ships; it stays and keeps the software working as the business changes. Lily runs wherever the work happens, in the cloud, on-premise, or at the edge, through InstaLILY's Small Data Center, built with NVIDIA technology. Founded in 2023 by Amit Shah and Sumantro Das, InstaLILY has raised nearly $100 million from Energize Capital, Insight Partners, and Home Depot Ventures. Headquartered in New York, with offices in San Francisco, London, and Toronto, InstaLILY serves leading companies across construction, industrial distribution, logistics, healthcare, and other operationally intensive industries. Learn more at https://instalily.ai/. The Traction Revenue grew 5x over the past year, and Lily has driven over $200M in new annual sales for a single customer. We serve some of the largest operators in our industries, including SRS Distribution (part of The Home Depot family), United Rentals, and Henry Schein, and we work closely with the Google DeepMind and NVIDIA ecosystems. How We Work We work in small teams with real ownership: clear problems, direct access to the customers whose work you're changing, and room to ship. Your code runs in live production systems inside billion-dollar operations, so you see your impact directly. People who do well here want that proximity to the work. We're growing fast, and the people who join now shape what this company becomes. Everything runs on three principles: Customers, Culture, and Code.About the Role As a Full Stack Software Engineer at InstaLILY, you'll own meaningful pieces of our AI agent platform: the core systems that let autonomous agents reason, act, and integrate into our enterprise customers' workflows. You'll work alongside the Lead Software Engineer and a team drawn from top-tier programs to design, build, and ship the platform features that show up in production at our customers. You'll work across the stack, from backend services and agent infrastructure to APIs and the web interfaces our customers actually touch. This role is deeply client-facing. You won't be coding in a vacuum and handing off to a customer success team. You'll be in the room with our customers from the start. You'll sit in working sessions with enterprise stakeholders, run technical discovery, translate messy real-world workflows into shipped features, and embed with customer teams during rollouts. The best engineers here are the ones who can switch between writing production code in the morning and walking a Fortune 500 VP through a system architecture in the afternoon. You need to code at a high bar, make architectural decisions you can defend, and explain them clearly to people who don't speak engineer. Responsibilities Own end-to-end design and delivery of features across the full stack: backend services, agent infrastructure, APIs, and customer-facing web UIs Build, ship, and operate LLM-powered systems: agents, RAG pipelines, tool-use frameworks, evaluation harnesses, and the supporting infrastructure that makes them reliable in production Lead technical discovery with new enterprise customers; sit with their teams, map their workflows, and translate what you hear into shipped product Embed with customer teams during deployments and rollouts; be the engineering presence in the room, not the one waiting for a Jira ticket Present architecture and technical tradeoffs to non-technical executives at our customers, and defend them under pressure Partner with the Growth team to turn customer feedback into roadmap; iterate on what's actually being used vs. what we thought...