Software Engineer (Full-stack, AI Team)

Numeral is building the automation backbone for internet commerce, starting with the painful world of sales tax compliance. We handle everything from registration to remittance, delivering a white-glove service so e-commerce businesses can stay focused on growing their products, customers, and teams.

Founded by early Stripe employees, backed by Benchmark Capital, and part of Y Combinator's W23 batch, Numeral has raised $57M+, has 2,500+ customers, and has tripled revenue year-over-year.

About the Role

We are hiring a Foundational AI Engineer to join the AI team. You will define the technical and architectural foundations of an early-stage startup building LLM-powered automation systems for an AI-native tax compliance platform.

What You'll Do

• Design and deploy production AI systems including tool-calling agents, model orchestration layers, and RAG pipelines.
• Implement LLM integrations using modern frameworks, MCP servers, and external model providers.
• Build backend services and APIs powering automated workflows.
• Make architectural decisions balancing latency, cost, reliability, and iteration speed.
• Own infrastructure and observability for AI and non-AI services.
• Define engineering best practices and AI safety standards.

Qualifications

• 7+ years building products in high-growth environments.
• 2+ years of LLM development experience.
• Active use of state-of-the-art AI development tools such as Cursor and Claude Code.
• Backend fluency: PostgreSQL, Redis, AWS.
• Frontend experience with TypeScript.
• Startup mindset and comfort with ambiguity.

Bonus

• Experience with fintech or tax systems.
• Experience with automation platforms (n8n, Zapier).
• Experience with MCP servers and agent frameworks.
• Experience with vector databases (Pinecone, HNSW).

Compensation & Location

• $175,000 to $300,000 + equity.
• New York or San Francisco (hybrid), remote considered in some cases.

Benefits

• Competitive equity.
• Medical, dental, and vision coverage.
• Wellness perks.
• 401(k).
• Office amenities and team events.