Founding Data Scientist

About Sela Sela is the market-leading AI voice agent for mortgage lenders. Founded in 2024, we’ve grown like crazy (~$0->13M in 20 months), and currently count 5 of the 10 largest independent mortgage banks in the U.S. as enterprise customers. If we’re successful, the cost of owning a home in the US will become ~1% cheaper. We’ve raised $21M across our Seed and Series A from top investors.   Why this is a huge opportunity Around 1% of the U.S. labor force works in phone sales, representing roughly $100B of annual salary, and the industry is poised at the brink of complete disruption. We are at the cutting edge of this economic transformation, one of the first companies creating real, durable economic value through applied AI. Buying a house is the largest financial decision most people make in their lives, and homeownership is tied to many other purchases, including life insurance, homeowners insurance, alarm systems, home renovations, solar panels, and more. By owning the mortgage vertical, we will own the relationship with the consumer, allowing us to serve as the essential AI infrastructure for high consideration consumer sales.   Why Join 1. Crazy growth: The market pull is exhilarating - we’ve grown 10x in the past 12 months and more than 100x since our seed round, all without a dedicated sales or marketing team. Building something that people want so badly is the best feeling you can have in a startup. 2. Team and Culture: We are a high-agency team where the bar is high and everyone makes the people around them better. Collaboration and intensity are core team values: people truly care about their work and their coworkers. At the same time, we don't take ourselves too seriously. 3. Challenging problems: Outperforming human sales teams on half a million daily calls is not easy. Low-latency, real-time infra. 99.9% uptime. Enterprise-grade privacy and security. Advanced simulation and evaluation systems. Flexible A/B testing. AI scheduler and dialer. We own the whole stack and we do not compromise on quality. 4. Well-funded: We’ve raised $21M+ in total funding, most recently a $15M Series A in June 2026.   What will you do - Help us build the top-performing AI sales agent in the world. - Analyze hundreds of millions of calls to understand what drives better sales outcomes. - Design and run experiments across every part of the sales call — what we say, how we say it, when we call, and more. - Build models that help us personalize and optimize calls for each lead. - Turn large, complex datasets into recommendations that directly improve our AI agents. - Partner closely with engineering to build a robust, scalable, and future-proof experimentation framework. What will you own - Experimentation across hundreds of millions of sales calls, from identifying opportunities to measuring results. - The methodology behind how we design experiments, measure outcomes, and make decisions. - Turning insights from our calls into improvements to our AI sales agents. - Ensuring our experimentation framework can support increasingly sophisticated experiments as we scale. - As our first data scientist, defining how data science is done at Sela and eventually the team we build. What are we looking for Must haves: - 4+ years of experience in data science, machine learning, experimentation, or a closely related field. - Strong statistical foundations and experience designing and analyzing experiments. - Strong Python and SQL skills and the ability to work with very large datasets. - Ability to take an ambiguous problem, figure out what to measure, and turn the results into actionable recommendations. - Strong technical judgment and the ability to work closely with engineers on experimentation systems. - High agency and the ability to operate without an established playbook. Nice to haves: - Experience designing experimentation or optimization systems at scale. - Experience with causal inference, personalization, ranking, or recommendation systems. - Experience working with LLMs, speech, or conversational data. - Experience at a fast-growing startup or as an early data science hire.   Benefits - $180k - $250k + equity - Top-of-market medical, dental, and vision coverage for you and your dependents - 401(k) with a top-of-market employer match - Unlimited PTO - Snacks, weekly team lunches, and dinner on Sela - Hybrid in-office schedule: four days a week together in SF, with a flexible remote day on Wednesdays