Staff Machine Learning Engineer

Overview Build and operate the ML platform that powers AppFolio’s AI-native Real Estate platform, ensuring scalable training, inference, and cost‑efficient operations across AWS and multi‑provider LLMs. Responsibilities Design and operate AppFolio's ML infrastructure on AWS, including ECS, SageMaker, GPU fleets, model serving, autoscaling, and cost controls. Optimize AI cost across all applications through routing, caching, batch vs. real‑time processing, model size selection, and inference economics. Maintain reliable multi‑provider LLM access across Google, OpenAI, and Anthropic, with fallbacks and abstractions. Build the training and fine‑tuning stack for small language models, including data pipelines, GPU orchestration, and evaluation. Productionize research prototypes with SLOs, on‑call rotations, and observability. Operate AppFolio's AI safety and authorization layer, including guardrails on AWS, scoped tool permissions, and human‑in‑the‑loop gates. Qualifications Experience building and operating production ML infrastructure at scale on AWS (ECS, SageMaker, GPUs, autoscaling, cost controls). Production experience with model serving for LLMs and custom models, understanding quantization, batching, and routing. Direct experience integrating with Google Vertex/Gemini, OpenAI, and Anthropic APIs in production. Strong Python, Docker, dependency management, and CI/CD for AI workloads. Experience with RAG and agents (LangChain, LangGraph, modern RAG patterns). Demonstrated cost optimization for AI workloads without regressing quality or latency. Hands‑on experience operating AI guardrails, scoped tool permissions, and authorization layers. Systems thinker, production builder, owner‑operator, strong desire to move fast, collaborative, and reliable mindset. Nice to Have Experience training small language models for production use. GPU performance tuning (vLLM, TensorRT, Triton, or similar). Prior staff‑level role in a company with a significant AI infra footprint. Experience with ontology‑driven systems or knowledge graphs supporting AI applications. Contributions to open‑source ML infrastructure or LLM tooling. Location Remote (San Francisco, CA; Denver, CO; Santa Barbara, CA; San Diego, CA) Compensation Base salary $200,000 – $250,000 per year. Total rewards include benefits and potential discretionary bonuses. Equal Opportunity Statement At AppFolio, we value diversity in backgrounds and perspectives and depend on it to drive our culture. AppFolio is a proud Equal Opportunity Employer, and we welcome individuals of any race, color, religion, sex, sexual orientation, gender identity, national origin, age, marital status, ancestry, physical or mental disability, or veteran status. #J-18808-Ljbffr