AI / ML Engineer

Location: San Francisco, California, US
Recruiter: Known
Date posted: Friday, November 21, 2025

Job Description:

About the Role

Youll be the technical founder driving the machine learning and AI backbone behind Known an intelligent, compatibility-driven dating platform that blends psychology, data, and human-like conversation. Youll design and ship the systems that make Known feel magical: personalized matching algorithms, adaptive recommendation loops, and natural voice/LLM-based interactions that help users connect meaningfully.

Youll work closely with the founding team (product, platform, and design) to shape both the data and ML foundations and the user-facing experiences that differentiate Known. This is a hands-on role with ownership across research, prototyping, and production deployment.

Responsibilities

• Design and implement multi-stage matching systems (embedding-based retrieval + LLM re-ranking) for compatibility scoring, search, and personalization.

• Develop and maintain ML pipelines for data ingestion, feature generation, model training, evaluation, and inference.

• Prototype and productionize agentic workflows for natural-language and voice interactions (e.g., AI-assisted intake interviews, voice matching, or conversation agents).

• Deploy and monitor ML models in production with guardrails for performance, fairness, and safety.

• Run offline & online experiments (A/B and multivariate) to measure real-world outcomes such as engagement, match success rate, and conversation quality.

• Collaborate cross-functionally with platform engineers and product designers to integrate AI seamlessly into the Known user experience.

Requirements

• 3+ years in applied ML or data science engineering roles, ideally working on recommendation, search, or personalization systems.

• Strong proficiency in Python and modern ML frameworks (PyTorch, TensorFlow, JAX, Hugging Face).

• Experience with LLMs, embeddings, and agentic workflows.

• Understanding of A/B testing and human-in-the-loop system design for model evaluation in production.

• Familiarity with ANN search systems and modern MLOps tools is a plus.

• Reinforcement learning or preference modeling experience is a strong plus.

• You care about building safe, fair, and human-centered AI experiences.
  

Example Projects

• Develop a user matching system based on profile information, onboarding transcripts and engagement behavior.

• Build a dynamic profile enrichment pipeline that integrates behavioral and linguistic features into user representations.

• Deploy a lightweight LLM-powered voice agent for user intake and conversational matchmaking.

• Create an evaluation harness combining offline metrics (AUC, NDCG) and online experiments (match acceptance, message rate).

• Build model monitoring and retraining loops informed by live interaction feedback.
  

Why This Role

This is an opportunity to define the technical DNA of a consumer AI product from day one to architect and deploy systems that combine data science, human psychology, and generative AI. Your work will directly shape how people connect, communicate, and build relationships in an AI-assisted world.

Apply for this job on Known