Staff ML Engineer: Build Production-Ready AI for High-Stakes Decisions

primerai; Pasadena (CA); On-site; USD 170,000 - 250,000; Full time

Job summary

Primer is building trusted, decision-ready AI for leaders, operators, and analysts. We seek a Staff Machine Learning Engineer who will own AI-driven products end-to-end—from prototype to production—across large language models, agentic systems, retrieval, embeddings, and fine-tuned models.

You’ll ship reliable systems at scale and drive real-world impact. You will partner with product and engineering leaders to define the technical roadmap, raise the engineering bar, and ensure the AI delivers

Qualifications

• BS, MS, or PhD in computer science or related field, or equivalent practical experience.
• 6+ years building production backend software with ML components.
• Strong knowledge of data structures, algorithms, and scalable systems.
• Hands-on depth with LLMs and agentic systems (prompt and context engineering, tool use, retrieval and RAG) and ML toolkit such as PyTorch.
• Fluency authoring production APIs in Python (Rust a plus).
• High agency and bias to action in ambiguous, fast-moving problems, with collaborative mindset.

Responsibilities

• Set technical and product direction across LLM, agentic, and NLP systems while shaping AI-driven experiences.
• Design and build distributed, tool-using conversational agents with multi-turn context and retrieval-grounded reasoning.
• Turn real-world data into trustworthy signals through entity recognition, relation extraction, summarization and knowledge-graph generation.
• Take models from checkpoint to production with low-latency, high-concurrency inference at scale.
• Create evals and labeled-data flywheels to prove and improve quality.
• Collaborate with product and engineering leaders to shape the technical roadmap and drive root-cause analysis when issues arise.
• Raise engineering standards with reusable patterns and best practices.

Skills

LLMs

Agentic systems

Retrieval

Embeddings

Fine-tuned models

Evaluation harnesses

Python APIs

PyTorch

Distributed systems

Decision-ready AI

Education

BS/MS/PhD in Computer Science

Job description

Primer is building trusted, decision-ready AI for leaders, operators, and analysts. We seek a Staff Machine Learning Engineer who will own AI-driven products end-to-end—from prototype to production—across large language models, agentic systems, retrieval, embeddings, and fine-tuned models.

You’ll ship reliable systems at scale and drive real-world impact. You will partner with product and engineering leaders to define the technical roadmap, raise the engineering bar, and ensure the AI delivers