Production AI Systems Architect & RAG Lead

Harnham; San Francisco (CA); On-site; USD 180,000 - 240,000; Full time

Job summary

Harnham in San Francisco is partnering with a high-growth, mission-driven SaaS company transforming AI across critical enterprise workflows, emphasizing reliability, auditability, and security. You will define how AI is architected, making foundational decisions across LLMs, retrieval systems, and agent-based workflows in production environments, shaping technical direction with tangible impact.

This is a high-impact role requiring ownership, strong Python expertise, and the ability to balance

Qualifications

• 5+ years of software engineering, including 3+ years working on ML or AI systems.
• Strong background in RAG, embeddings, reranking, and vector databases.
• Experience designing evaluation systems and improving models through quantitative analysis.
• Strong Python skills, with solid software engineering fundamentals.
• Experience making architectural decisions that influence team or org direction.
• Strong understanding of production systems, including reliability, observability, and cost tradeoffs.
• Ability to break down ambiguous problems and operate with a high degree of ownership.
• Clear communication skills and experience working cross-functionally.

Responsibilities

• Design and own production AI systems end-to-end, including LLM pipelines, retrieval systems, and orchestration layers.
• Build and scale RAG systems, reranking pipelines, and vector-based search infrastructure.
• Define evaluation frameworks to measure retrieval quality, reasoning accuracy, and system performance.
• Analyze production behavior, identify failure modes, and drive improvements based on data.
• Make key architectural decisions across model infrastructure, tooling, and workflows.
• Partner closely with product, platform, and domain teams to translate complex requirements into scalable systems.
• Lead best practices for building reliable, observable, and cost-efficient AI systems.

Skills

ML/AI systems

Python

System design

Cross-functional collaboration

Observability

Reliability

Ownership

Tools

Pinecone

FAISS

Chroma

Job description

Harnham in San Francisco is partnering with a high-growth, mission-driven SaaS company transforming AI across critical enterprise workflows, emphasizing reliability, auditability, and security. You will define how AI is architected, making foundational decisions across LLMs, retrieval systems, and agent-based workflows in production environments, shaping technical direction with tangible impact.

This is a high-impact role requiring ownership, strong Python expertise, and the ability to balance