Senior ML Engineer, Voice AI & Real-Time Agents

AppFolio, Inc.; Santa Barbara (CA); Hybrid; USD 167,000 - 230,000; Full time

Job summary

AppFolio, Inc. is seeking a Senior Machine Learning Engineer to design and ship voice and text agents within Realm-X, its AI-native platform.

You’ll work across LLM agent frameworks, real-time voice tech, and streaming infrastructure to deliver scalable experiences for customers. You will collaborate with Product, Voice channel, and ML Platform teams to translate research into reliable, low-latency pipelines that scale across our user base.

Qualifications

• You have 5+ years of experience developing and scaling web-based applications.
• You have shipped production AI agents serving real users in voice and/or text channels.
• You excel at building pipelines and systems, not just models.
• You move fast, deliver impact, and work well with others.

Responsibilities

• Ship voice and text agent pipelines for real-time customer interactions.
• Balance reasoning depth with latency across models and routing strategies.
• Lead a small pod of ML and platform engineers; improve observability and incident response.
• Define KPIs, eval harnesses, and acceptance criteria for agent quality.
• Optimize voice latency and cost via targeted fine-tuning and inference.

Skills

Agent frameworks

Voice stack

LLM fluency

Telephony & cloud

Engineering

ML fundamentals

Leadership

Education

Bachelor’s / Master’s / PhD in CS or related

Tools

Twilio

Docker

AWS

WebSockets

Job description

AppFolio, Inc. is seeking a Senior Machine Learning Engineer to design and ship voice and text agents within Realm-X, its AI-native platform.

You’ll work across LLM agent frameworks, real-time voice tech, and streaming infrastructure to deliver scalable experiences for customers. You will collaborate with Product, Voice channel, and ML Platform teams to translate research into reliable, low-latency pipelines that scale across our user base.