Software Engineer (AI)

Numeral; New York (NY); On-site; USD 180,000 - 250,000; Full time

Benefits offered by this job

Equity

Health insurance

Wellness perks (Headspace, Peloton)

401(k) matching

Office lunch and snacks

Team offsites

Job summary

Numeral is building an AI-native tax platform and seeking a Foundational AI Engineer to own the technical foundations and end-to-end AI workflows. You’ll design tool-calling agents, orchestration layers, and MCP-style integrations while scaling backend services for real-world customer needs.

You will collaborate with product, design, and data teams, establishing engineering best practices, AI safety norms, and a culture of ownership as Numeral grows rapidly in a customer-centric way.

Qualifications

• 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.

Responsibilities

• 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.

Skills

LLM development

Backend engineering

Frontend development

Cloud services

Communication

Startup mindset

Tools

Cursor

Claude Code

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!