Software Engineer (AI)

About Numeral: Numeral is transforming how taxes get done. Digital businesses are currently bogged down by a painful web of regulations across 47 states and 70+ countries. We’re eliminating this burden so teams can focus on their core mission. We’re the largest and fastest-growing AI-native tax solution. Started in 2023, Numeral has raised over $57M from Benchmark, Mayfield, Y-Combinator, and many others. We now serve over 3,000 paying customers and have more than tripled our revenue every year in our history. About the role: We’re looking for a Foundational AI Engineer who thrives in ambiguity, enjoys building real-world AI systems end-to-end, and wants to define the technical and architectural foundations of an early-stage startup. This is a hands-on role for someone who wants to design and implement LLM-powered automation systems: model orchestration, tool calling, MCP-style integrations, agentic workflows, and automation-driven tooling. What you’ll do: Design, build, and operate production AI systems, including tool-calling agents, model orchestration layers, and RAG. Implement and maintain AI integrations using modern frameworks, MCP servers, and external model providers. Build and evolve scalable backend services and APIs that power automated workflows and customer-facing features. Think in automation and workflows: design systems using tools like n8n, Claude Co [... source excerpt omitted ...] ed. Own infrastructure, observability, and performance for both AI and non-AI services. Collaborate closely with product, design, and data teams to ship features that solve real customer problems. Help define engineering best practices, AI safety/reliability norms, and our overall technical culture. What you’ll bring: 7+ years of experience building products in high-growth environments. 2+ years of experience building with LLMs. Avid use of state-of-the-art AI development tools such as Cursor and Claude Code. Fluency with backend technologies like PostgreSQL, Redis, and cloud services (AWS preferred). Experience with frontend development, especially TypeScript and its ec [... source excerpt omitted ...] Startup mindset: Not scared of ambiguity and hungry for rapid growth Intensity & Ownership: This is not a 9-5 — we’re scaling rapidly and have a massive opportunity ahead of us. Customer Obsession: You deeply care about the user experience and solving their problems Even better: Experience in payments, tax, accounting, or regulatory tech. Experience with automation tools (n8n, Zapier-style systems, workflow engines) or building internal automation platforms. Familiarity with MCPs, tool calls, agent frameworks, or model orchestration patterns. Understanding of vector databases and concepts (such as Pinecone, HNSW). What we offer: Competitive salary and equity - you’ll sha