Senior Staff Engineer, AI

Location: Prefer Onsite NYC or SF. Open to exceptional Remote candidates Employment Type: Full-Time Hiring Manager: Andrew Rosen, Head of Engineering ABOUT ARC Arc is building the first AI-native business cash management platform. We empower high-growth companies to manage, analyze, and act on their financial data through a unified cash management, treasury, and debt-financing platform—powered by AI. Founded in 2021, Arc is backed by world-class investors (Series A), supports thousands of technology companies as customers, and manages billions of dollars in transaction volume. With offices in NYC and SF, we operate on a Monday–Wednesday in-office model (Thu–Fri optional in-office or WFH). We’re at an inflection point. Large enough to matter; small enough to innovate. THE ROLE We are seeking a Senior Staff Engineer, AI to join Arc’s engineering organization as a key technical leader. This is a foundational AI role, responsible for driving the research direction, execution, and delivery of Arc’s AI-powered products across both cash management and debt marketplace products. WHAT YOU’LL DO LEADERSHIP & STRATEGY - Drive Arc’s most critical AI initiatives end-to-end in a cross-functional environment. - Serve as a company-wide thought leader on foundational models, LLMs, agent systems, retrieval, and emerging research. - Establish and refine Arc’s internal AI strategy, research direction, and technology roadmap. EXECUTION & PRODUCT IMPACT - Collaborate with engineering, product, design, and leadership to build and improve AI-powered financial products. - Build evaluation frameworks, model-improvement infrastructure, and production-grade AI systems. - Rapidly prototype 0→1 and MVP experiences to unlock new value for Arc customers. - Ship projects frequently and consistently, with strong bias to action. TECHNICAL EXCELLENCE - Architect and implement Generative AI applications using: - Agentic workflows - RAG systems - State-of-the-art model leveraging techniques - Optimize for inference performance, token efficiency, latency, and cost. - Contribute to platform-level systems in Python and Typescript. WHAT YOU BRING MINIMUM QUALIFICATIONS - 8+ years of engineering experience, including 1+ years building AI-based applications. - Advanced degree in Computer Science or related field; Masters/PhD preferred - Strong background in Generative AI, LLMs, and modern applied AI toolchains. - Demonstrated success building agentic systems, RAG architectures, or state-of-the-art model integrations. - Experience building evaluation pipelines for foundational-model applications. - Strong software engineering fundamentals. - Proven ability to independently drive 0→1, MVP development, and rapid prototyping. PREFERRED EXPERIENCE - Startup experience, ideally combined with exposure to 1–2 mid-size or large organizations. - Fintech or B2B product experience. - Applied AI experience including infra, model improvement loops, and optimization. - Python, Typescript, model performance tuning, and workflow automation. WHY JOIN ARC NOW? - Category creation: You’ll build the first AI platform for business cash business management. - Massive market: Banking + treasury + AI automation is a multi-trillion-dollar opportunity. - PMF already secured: Arc has elite customers, strong economics, and hyper-growth. - High impact: Staff engineers here are foundational—this role moves the roadmap. - Lean, elite team: Work with exceptional builders; every engineer is high-leverage.