Staff ML Engineer — Production-Scale AI Infra

Appfolio; Santa Barbara (CA); On-site; USD 200,000 - 275,000; Full time

Job summary

AppFolio is hiring a Staff Machine Learning Engineer to advance the ML platform powering Realm-X. You’ll train, fine-tune, infer, and evaluate AI models while keeping the cloud cost-efficient and always-on. You’ll work across ML infrastructure, applied AI, and cost discipline to scale Realm-X for our broad customer base.

You’ll collaborate with Voice & Agents and Research ML teams to harden prototypes into production systems with observability, SLOs, and secure guardrails for AI applications.

Qualifications

• ML infra at scale: built and operated production ML infrastructure on AWS - ECS, SageMaker, GPUs, autoscaling, cost controls.
• Inference platforms: production model serving for LLMs and custom models with batching and routing.
• Provider breadth: integrated with Google Vertex/Gemini, OpenAI, and Anthropic APIs in production.
• Training capability: trained or fine-tuned language models end-to-end; deep learning, evaluation, inference.
• Cloud-native engineering: strong Python, Docker, dependency management, and CI/CD for AI workloads.
• RAG & agents: working knowledge of LangChain / LangGraph and modern RAG patterns over data.

Responsibilities

• Design and operate AppFolio's ML infrastructure on AWS - ECS, SageMaker, GPU fleets, model serving, autoscaling, and cost controls.
• Drive AI cost discipline: optimize cost across AI apps including routing, caching, batching, and inference economics.
• Maintain reliable multi-provider LLM access across Google, OpenAI, and Anthropic with sensible fallbacks.
• Build training and fine-tuning stack for small language models, including data pipelines and GPU orchestration.
• Partner with Voice & Agents and Research ML engineers to productionize prototypes with SLOs and observability.
• Operate AI safety and authorization: guardrails, tool permissions, and human-in-the-loop gates.

Skills

ML infrastructure

Production ML systems

Cloud-native engineering

Python

CI/CD for AI workloads

RAG & agents

Cost optimization

Hardware/cloud cost control

Education

Bachelor's, Master's, or Ph.D. in Computer Science or related technical discipline

Tools

AWS ECS

SageMaker

GPUs

LangChain

LangGraph

Job description

AppFolio is hiring a Staff Machine Learning Engineer to advance the ML platform powering Realm-X. You’ll train, fine-tune, infer, and evaluate AI models while keeping the cloud cost-efficient and always-on. You’ll work across ML infrastructure, applied AI, and cost discipline to scale Realm-X for our broad customer base.

You’ll collaborate with Voice & Agents and Research ML teams to harden prototypes into production systems with observability, SLOs, and secure guardrails for AI applications.