Senior AI Engineer at Arist (S20) $180K - $250K • 0.50% - 1.00% Deliver effective learning at scale US / Remote (US) Full-time US citizen/visa only 3+ years About Arist Backed by Y Combinator, Acadian Ventures, and Soma Capital, Arist is a text message learning platform helping Fortune 500 companies and large organizations — including DuPont, GE, and the State of California — create, deploy, and assess text message courses. Our long-term vision is to deliver critical knowledge and training to anyone in the world, regardless of traditional learning barriers, one text message at a time. What's a text message course? A series of texts, images/GIFs, and interactive exercises/questions delivered over 5 to 30 days via SMS or WhatsApp. Backed by research from Stanford and Harvard, text message courses see ~10x the completion and satisfaction rates of other learning mediums. In fact, we view text message courses as a brand-new content medium, with a variety of impactful use cases ranging from preventing misinformation to COVID-19 training in refugee camps to DEI training for startups. Why text messages? A majority of the world's population — including frontline employees, distributed teams, and remote audiences — has access to SMS and WhatsApp. Meanwhile, internet access is limited globally, making video courses inaccessible to over 3 billion people, including 30 million Americans. As well, it can also take months to build a traditional workshop or video course, while text message courses can be built and deployed in a day — by one person — ensuring frictionless transfer of knowledge. Writers have to get to the point, so learners get the most valuable insights, concepts, and case studies. The best part? 95% of people read a text within 3 minutes. As a result, we help create and deliver content employees love in a way that they will actually read and engage with. Don't take our word for it — try a text message course about text message courses here. About the role Skills: ML, Ruby on Rails Join the founding AI team at Arist, the leading enablement platform used by teams at Novartis, HP, and Intuit. You'll work closely with cofounders and our founding engineers to bring agentic, production-grade AI workflows (actually used by Enterprises) to life. What you'll build: Agentic workflows using LLMs for real-world task execution Customization layers for org-specific logic Voice-based and message-based learning agents AI pipelines with evaluation, feedback loops, and monitoring Multi-agent orchestration and AI system infra We’re looking for someone who: Has 5+ years of ML experience (PyTorch, TensorFlow), and 2+ years with LLMs (Hugging Face, OpenAI, Anthropic) Has built and deployed production AI systems, including RAG and vector search Knows prompt engineering, AI safety, and content filtering best practices Ideally has expert-level Rails experience (3+ years), including REST APIs, PostgreSQL, ActiveRecord, and RSpec Can lead AI integration in full-stack environments and collaborate across teams Understands LangChain, LlamaIndex, or similar frameworks (or can ramp fast) Communicates clearly, moves fast, and thrives in ambiguity Bonus if you’ve: Built agent-based AI features inside Rails apps Led AI-powered UI/UX design or AI feature launches Shipped real-time inference systems or AI content generation at scale If you're excited to ship practical, AI-first systems that actually get used by leading global orgs, reach out. Technology Arist runs scalable agentic AI services that integrate both private (Bedrock-hosted Claude, Mistral, Llama) and public (OpenAI, Perplexity) LLMs that drive workflows in a core Ruby on Rails/Vue.js product with real-time messaging and event-driven processing on cloud-native AWS infrastructure.