AI & ML Engineer

ABOUT SANDSTONE Sandstone is on a mission to elevate in-house legal from a support function into a true strategic partner. From day one, we’ve been clear about what we are—and are not. We are not replacing in-house legal teams. We are building a platform that amplifies them. Our platform enables modern legal teams to move at the speed of AI, deliver better outcomes, and create measurable business value. We unify legal data, power end-to-end workflows, and organize business context within the tools teams already use. Sandstone is the home for AI-native legal departments. Today, Sandstone is trusted by Fortune 500 companies and fast-growing innovators alike. We ship quickly, iterate relentlessly, and scale with intention. When you join Sandstone, you become part of a team that believes deeply in the compounding power of collaboration, rigorous problem-solving, and obsessive attention to detail. Our engineering team is elite, our lawyers ship code every day, and we are dedicated to building the most delightful product an in-house lawyer opens in the morning—and closes at the end of the day. We work five days a week out of our offices in the Lower East Side. Dogs welcome; shoes optional; chess encouraged. THE ROLE Sandstone is building the AI-native operating system for in-house legal teams. As an AI & ML Engineer, you will build the systems that make that possible: agents that reason over contracts and business context, retrieval systems that surface the right precedent, document understanding pipelines that turn legal work into structured intelligence, and evals that help us measure and improve quality. This is an applied AI product engineering role. You will own production AI systems end-to-end, from problem definition and data strategy through model behavior, orchestration, reliability, UX, and launch. You will work closely with engineers, lawyers, designers, and customers to translate legal judgment into product behavior. This is not a research role, a prompt engineering role, or a narrow ML infrastructure role. We are looking for product-minded AI engineers who can move quickly through ambiguity, work across the stack, and build systems that are useful, trustworthy, and delightful for lawyers to use every day. WHAT YOU’LL DO - Build production AI systems for legal workflows such as contract review, redlining, legal intake, drafting, negotiation, search, and knowledge management - Improve retrieval and context systems that reason over contracts, playbooks, precedent, customer data, and business context - Build document parsing and understanding pipelines that extract structure, entities, obligations, issues, and negotiation context from complex legal documents - Develop agentic and workflow-based LLM systems for long-running, multi-step legal tasks - Create evals, datasets, metrics, and feedback loops to measure quality, reliability, cost, and latency - Partner with lawyers and customers to turn real workflow feedback into product improvements - Work across backend AI services, data pipelines, APIs, and product surfaces - Make pragmatic system design decisions about when to use frontier models, smaller models, retrieval, rules, human review, or product design WHAT WE LOOK FOR - 4+ years of experience as an AI engineer, ML engineer, full-stack engineer, product engineer, data scientist, or similar role - Experience shipping applied AI or LLM-powered products, especially involving retrieval, agents, evals, document understanding, structured extraction, or workflow orchestration - Strong software engineering fundamentals and comfort working across backend systems, data pipelines, APIs, and product-facing surfaces - Ability to own ambiguous technical and product problems from discovery through launch and iteration - Strong judgment around quality, latency, cost, reliability, observability, security, and UX tradeoffs - Excitement about working with lawyers and customers to encode domain expertise into product behavior - Bias toward shipping, measuring, and improving rather than waiting for perfect specs or perfect models - Clear communication, especially when explaining AI behavior and system tradeoffs to technical and non-technical teammates - Bonus: experience with legal, financial, enterprise SaaS, search, document AI, workflow automation, or other domains where correctness and trust matter WORKING AT SANDSTONE: BENEFITS & PERKS - Comprehensive health, dental, and vision insurance; 401K - 12 weeks paid parental leave - Flexible time off (20+ days PTO) - Annual learning & development stipend - Technology stipend, including unlimited spend on AI tooling - Daily lunch for in-office team members At Sandstone, we value high ownership, flexibility, and curiosity. You'll have an outsized impact, work closely with ambitious colleagues, and help transform how legal teams work for the modern age.