Software Engineer (AI)

Job description

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 Code-style agents, or similar orchestration approaches. - Make architectural decisions that balance latency, cost, reliability, and iteration speed. - 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 ecosystem. - Strong product sense, balancing performance, flexibility, and speed. - Comfortable working in dynamic startup environments with evolving needs. - Excellent communication and collaboration skills. - 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 share directly in the company’s success - Full medical, dental, and vision coverage - Wellness perks like Headspace and the Peloton One App - 401(k) to help you build long-term financial security - Lunch and snacks when you’re in the office - Regular team offsites and company events as we grow - A culture built on ownership - your work matters and people will see it!