AI Engineer

About StackOne: StackOne is the AI Integration Gateway for SaaS products and AI Agents. Backed by GV and Workday Ventures ($24M raised), we help builders of SaaS platforms and AI Agents orchestrate hundreds of scalable, accurate, and enterprise-grade integrations. Our platform combines 25,000 pre-mapped actions on 200 connectors, an AI-powered integration development toolkit, plus security by design: a real-time architecture, managed authentication and permissions, and end-to-end observability. Join us on our fast trajectory to build the future of agentic integrations. With an AI-native integration toolkit that delivers real-time execution, managed authentication, granular permissions, and full observability, all built with safety at its core, we’re now doubling down on AI R&D & creating our own lab to push the boundaries of tool calling for agents: training specialized LLMs designed to outperform general-purpose models in what matters most: precision, reliability, and safety in agentic execution. ABOUT THE ROLE You'll help build a world where users of any agents can integrate with the tool of their choice in one click thanks to StackOne. We are looking for a Software Engineer with a strong background in AI production-grade applications with professional experience working with LLMs (eg: GPT, Anthropic and others). In this role, you will deliver AI features and products end-to-end and work with the wider AI team of StackOne (comprising of AI researchers and other AI engineers). You will report directly to the CTO. RESPONSIBILITIES - Act as a full-stack engineer: design, build, and ship features across frontend, backend, and infrastructure. - Leverage AI models to accelerate development, while maintaining best-in-class reliability, testing, and code quality. - Build and maintain inference pipelines, embeddings, retrieval, and orchestration systems. - Integrate tool-calling and MCP (Model Context Protocol) patterns into product features. - Ship and maintain open-sourc