Machine Learning Engineer Intern

We’re a community of dreamers, big thinkers, problem solvers, active listeners, and multipliers. At every opportunity, we set the pace while delivering innovation built to carry real estate into the future. Where customers are empowered to take on any opportunity. Because together, we have the power to create extraordinary outcomes for our customers, our communities, and ourselves. Realm-X is AppFolio's AI-native platform powering this transformation. It enables a new generation of intelligent capabilities across our products, including Realm-X Assistant (copilot), Flows (AI Agentic workflows) and Performers (autonomous AI Agents). Realm-X serves as both a foundation for internal teams to build and scale AI-powered products , and a core layer delivering intelligent, high-impact experiences directly to our customers . At its core, Realm-X is built on a structured domain ontology and a set of shared business primitives —such as transactions, actions, reports, metrics, and skills—that enable AI systems to deeply understand and operate across the full context of property management workflows. This foundation allows us to build context-aware, action-oriented AI systems that go beyond simple assistance to power real automation and decision-making. We're hiring a Senior Machine Learning Engineer to design and ship the next generation of voice and conversational AI agents within Realm-X. This role helps define AppFolio's production voice and chat agent pipelines, working at the intersection of LLM agent frameworks, real-time voice technology, and streaming infrastructure. You will work with Product, Voice channel, and ML Platform teams to translate cutting-edge agent and voice research into reliable, low-latency, multi-channel experiences that scale across our entire customer base. Ship Voice & Text Agents: Architect and ship voice and text agent pipelines that handle real-time, multi-turn customer interactions. Lead a Pod: Lead a small pod of ML and platform engineers; Define Quality: Partner with Product and Voice channel teams to define KPIs, eval harnesses, and acceptance criteria for agent quality. Drive selective Small Language Model (SLM) fine-tuning and inference optimization for voice latency and cost. You have 5+ years of experience developing and scaling web-based applications, preferably in a SaaS environment. You have shipped production AI agents serving real users in voice and/or text channels. You think in pipelines and systems, not just models. You value work-life balance as a foundation for sustained high performance. Deep, shipped experience with LangChain, LangGraph, LangSmith, and LangChain Deep Agents (or equivalent agent frameworks). Hands-on with Voice-to-Voice models and traditional TTS / STT pipelines; Strong grasp of LLM reasoning behavior, tool use, structured output, and reasoning-vs-latency trade-offs across providers. Telephony & cloud: Production experience with Twilio (or comparable telephony) and AWS. Expert Python, async programming, and WebSockets for real-time, bidirectional streaming. ML fundamentals: Solid foundation in deep learning, model evaluation, and inference optimization; able to deploy with Docker on AWS. Bachelor’s, Master’s, or Ph.D. in Computer Science or related technical discipline. Experience fine-tuning Small Language Models for domain-specific voice applications. Familiarity with RAG over structured business data and tool-using agents over API surfaces. Prior experience in regulated or customer-facing industries with strict reliability requirements. Publicly verifiable work on GitHub, in open-source agent frameworks, or in community competitions. Find out more about our locations by visiting our site . The actual compensation for this role will be determined by a variety of factors, including but not limited to the candidate’s skills, education, experience, and internal equity. The compensation range listed here does not include additional benefits or any discretionary bonuses you may be eligible for based on your role and/or employment type. Regular full-time employees are eligible for benefits - see here . Our innovative platform and trusted partnership enable our customers to connect communities, increase operational efficiency, and grow their business. Grow | We enable a culture of high performance, where delivering results is recognized by opportunities for growth and compelling total rewards. Impact | We are creating a world where living in, investing in, managing, and supporting communities feels magical and effortless, freeing people to thrive. We learn as much from each other as we do our customers and our communities. Connect | We excel at hybrid work by fostering an environment that feels flexible, personal and connected, no matter where we are. At AppFolio, we value diversity in backgrounds and perspectives and depend on it to drive our innovative culture. This means that no matter what race, color, religion, sex, sexual orientation, gender identification, national origin, age, marital status, ancestry, physical or mental disability, or veteran status, you’re always welcome at AppFolio.