Sr. Machine Learning Engineer

Salary: $139,000 - 179,000 per year Requirements:

• We have shipped production AI agents that serve real users across voice and/or text channels.
• We think in terms of pipelines and systems, not only individual models.
• We move quickly, deliver meaningful outcomes, and exercise strong engineering judgment.
• We are collaborative, humble, low-ego, and we help elevate the people around us.
• We value work-life balance as the basis for sustained high performance.
• We bring deep, hands-on experience with agent frameworks such as LangChain, LangGraph, LangSmith, and LangChain Deep Agents, or comparable tools.
• We have practical experience with voice-to-voice models and traditional TTS/STT architectures, including the trade-offs between end-to-end voice systems and modular STT-LLM-TTS stacks.
• We have strong fluency in LLM behavior, tool use, structured outputs, and reasoning-versus-latency trade-offs across providers.
• We have production experience with Twilio or similar telephony platforms, as well as AWS.
• We are expert-level in Python, async programming, and WebSockets for real-time bidirectional streaming.
• We have a solid foundation in deep learning, model evaluation, and inference optimization, and we can deploy with Docker on AWS.
• We have demonstrated leadership ability, including mentoring engineers and partnering credibly with Product and Design.
• We have experience fine-tuning Small Language Models for domain-specific voice applications.
• We are familiar with RAG over structured business data and tool-using agents over API surfaces.
• We have worked in regulated or customer-facing environments with strict reliability expectations.
• We can show publicly verifiable work on GitHub, in open-source agent frameworks, or in community competitions.

• We will architect and deliver voice and text agent pipelines that support real-time, multi-turn customer conversations.
• We will make thoughtful trade-offs between reasoning depth and latency across frontier models, smaller models, and routing approaches.
• We will lead a small pod of ML and platform engineers and raise the standard for agent evaluation, observability, and incident response.
• We will work with Product and Voice channel partners to define KPIs, evaluation harnesses, and acceptance criteria for agent quality.
• We will drive selective fine-tuning and inference optimization of Small Language Models to improve voice latency and cost.
• We will translate advanced agent and voice research into dependable, low-latency, multi-channel experiences at scale.
• We will collaborate with Product, Voice channel, and ML Platform teams to build production-ready voice and conversational AI systems.

• AI
• AI Agents
• API
• AWS
• Architect
• Docker
• Fine-tuning
• GitHub
• Support
• LLM
• Python
• RAG
• Cloud
• Copilot
• Excel
• Machine Learning

More:

We are AppFolio, the technology leader shaping the future of the real estate industry with an AI-native platform that helps property managers work more intelligently, residents live better, and business processes run more efficiently. Our Realm-X platform powers next-generation AI capabilities such as assistants, agentic workflows, and autonomous agents across our products. We offer a competitive compensation range of 167,200 to 209,000 base pay, along with a comprehensive Total Rewards package and benefits for regular full-time employees. We support hybrid work, encourage growth through coaching and mentorship, and foster a culture built on impact, learning, connection, and inclusion. Late-stage candidates complete an in-person meeting as part of our hiring process.

last updated 33 week of 2026