Foundational AI Engineer

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.

• 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).

• 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!

• Numeral is transforming how taxes get done. Digital businesses are currently bogged down by a painful web of regulations across 47 states and 50+ 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 2,500 paying customers and have more than tripled our revenue every year in our history.
• We’re primarily hiring in our SF and NY offices, but do hire remotely in some cases