Senior Machine Learning Scientist

About Us Keystone AI is an AI customer service company whose mission is to make customer service extraordinary for everyone. We're driven to raise a new standard of quality customer service at scale, enabling enterprise companies to deliver experiences that people love–instant, proactive, personalized, and effortless. Keystone AI is an AI transformation platform and partner—combining strategic expertise with powerful AI agent management technology to accelerate businesses’ AI maturity to keep them ahead of the curve. With Keystone AI , 83% of customer conversations—and counting—are effortlessly resolved through automation, giving teams more time back, companies more resources to focus on growth, and customers more life to focus on what matters most to them. Established in 2016, Keystone AI is a Canadian company that has powered over 5.5 billion interactions for leading brands like Square, YETI, IPSY, and Monday.com , saving millions of hours of human effort. Backed with over $250M in funding from tier-one investors including Accel, Bessemer, FirstMark, Spark, and Version One Ventures, Keystone AI is a pioneer in the management and application of AI in customer service. At Keystone AI , we see growth as a reflection of each individual owner’s personal growth. That’s why our values are rooted in driving progress and continuous improvement. If you’re ambitious and eager to grow, Keystone AI could be the place for you. Learn more at www.ada.cx . As a Senior ML Scientist at Keystone AI , you will own the quality and reliability of the AI features that power our AI Agent platform for customer support. You will partner with Product Managers, Engineers, and Designers to frame problems, design experiments, and make evidence-based decisions that improve outcomes for customers and end users. You will primarily deliver simple and highly reusable evaluation and analysis code, and you will collaborate with engineers to productionize changes. To be successful, you will develop a deep understanding of Keystone AI ’s product and empathize with our users to find the best ways to solve customer problems. If you’re excited to shape the future of AI-driven customer support, we would love to hear from you. About You 5+ years of industry experience as a Data Scientist, Machine Learning Engineer, or similar with shipped work that moved product metrics Deep experience applying large language models to customer problems Excellent communicator, able to explain experimental results and complex ML concepts to diverse audiences You design reliable experiments and datasets that translate to production impact Strong software skills in Python, writing clean, production-ready code and documents Outcomes Run rapid, reliable experiments with sound statistical methods, reproducible pipelines, and clear readouts that drive product decisions Lead design choices across model selection, retrieval and grounding, prompting, and tool use, framing tradeoffs in quality, safety, cost, and latency Reduce critical AI failure modes, for example hallucinations and prompt injection, through targeted testing and red teaming Partner with PM, Engineering, and Design to prioritize customer use cases and failure modes, turning insights into changes that improve automated resolutions, CSAT, cost per conversation, and latency Coach and mentor peers in the Product Development org in AI feature design, experimentation, and measurement. Provide crisp and actionable feedback to help raise the standard for AI feature quality Benefits & Perks At Keystone AI , you’ll not only build extraordinary products but also thrive in an environment designed for your success. We prioritize your well-being, growth, and work-life balance. Here’s what we offer: Benefits Unlimited Vacation: Recharge when you need to. Comprehensive Benefits: Extended health coverage, dental, vision, travel, and life insurance. Wellness Account: Empowering you to invest in your overall well-being and lifestyle. Employee & Family Assistance Plan: Resources to support you and your loved ones. Perks Flexible Work Schedule: Balance your work and personal life. Remote-First, In-Person Friendly: Options to work from home or at our local hub. Learning & Development Budget: Invest in your long-term growth goals and skills. Work from Home Budget: Equipping you with the tools and support for a seamless remote work experience. Access to Cutting-Edge AI Tools: Work with the best AI tech stack in the industry. Hands-On with LLMs: Enhance your expertise in leveraging large language models. A Thriving Industry: Join the forefront of innovation in AI, shaping the future of technology. The above Benefits and Perks only apply to full-time, permanent employees. As part of our recruitment process, we may use AI enabled tools to support certain aspects of hiring, such as interview note-taking. All hiring decisions are made by our team. Thank you for your interest in joining us at Keystone AI . Due to the high volume of applications, we will only contact candidates whose qualifications match closely to the require