Staff ML Engineer: End-to-End AI Systems

InvestedintheMission; United States; On-site; USD 180,000 - 280,000; Full time

Benefits offered by this job

Medical/Dental/Vision

Fertility benefits

Mental health support

Gym membership

401(k)

Remote work stipend

Internet allowance

Job summary

Primer is seeking a Staff Machine Learning Engineer to own AI-driven products end to end, from prototype ideas to production systems. You’ll work across the modern stack—LLMs, agentic systems, retrieval, embeddings, fine-tuned models, and evaluation harnesses—driving reliable, scalable solutions that impact critical decisions.

You will collaborate with product, engineering, and other technical leaders to design, implement, and operate the next generation of AI-enabled experiences at scale.

Qualifications

• BS, MS, or PhD in computer science, or equivalent practical experience.
• 6+ years building production backend software, with a track record of shipping and operating ML-driven functionality.
• Mastery of data structures and algorithms, and the judgment to translate user needs into practical solutions.
• Hands-on depth with LLMs and agentic systems (prompt and context engineering, tool use, retrieval and RAG) and the broader ML toolkit such as PyTorch, plus experience defining evals to measure and improve quality.
• Fluency authoring production APIs in Python (Rust a plus).
• High agency and a bias to action in ambiguous, fast-moving problems, plus the curiosity, generosity, and love of teaching that lifts a whole team.

Responsibilities

• Set both technical and product direction, making the strategic bets across our LLM, agentic, and NLP systems while shaping how we design AI-driven experiences and set expectations with users.
• Design and build the distributed, agentic systems behind our products at company-wide scale: tool-using conversational agents, multi-turn context, retrieval-grounded reasoning, and the orchestration that ties them together.
• Turn massive, messy, real-world data into the trustworthy signal agents' reason over: entity recognition and linking, relation extraction, summarization, semantic search, and knowledge-graph generation.
• Take models from checkpoint to production: package, deploy, and operate low-latency, high-concurrency inference (Triton, vLLM, GPU-backed serving) that stays fast and reliable under real load.
• Build the evals and labeled-data flywheels that steer the work rather than gate it, turning “it feels better” into proof you can act on.
• Partner with and influence cross-functional teams to shape the technical roadmap, and drive issues to root cause when quality or operations are on the line.
• Raise the engineering bar with better patterns, better practices, and a standard other engineers want to match.

Skills

Backend experience

ML-driven features

LLMs

Agentic systems

Python APIs

Rust

Education

Bachelor's / MS / PhD in CS

Tools

PyTorch

Rust

Job description

Primer is seeking a Staff Machine Learning Engineer to own AI-driven products end to end, from prototype ideas to production systems. You’ll work across the modern stack—LLMs, agentic systems, retrieval, embeddings, fine-tuned models, and evaluation harnesses—driving reliable, scalable solutions that impact critical decisions.

You will collaborate with product, engineering, and other technical leaders to design, implement, and operate the next generation of AI-enabled experiences at scale.