Principal AI Engineer

Harrington Starr; New York (NY); On-site; USD 180,000 - 280,000; Full time

Benefits offered by this job

Bonus

Equity

Competitive compensation

Job summary

Harrington Starr in New York is seeking a Principal AI Engineer to shape the next generation of AI capabilities within a capital markets technology platform. This hands-on technical leadership role blends architecture, delivery, and product ownership, with scope to influence systems end-to-end.

You will mentor teams, drive production LLM deployments, and partner with engineering leadership on strategy, while delivering scalable AI-powered services in a fast-paced environment.

Qualifications

• Production-grade LLM applications experience.
• Strong background with RAG, AI agents and modern AI frameworks.
• Experience with vector databases, cloud platforms and scalable distributed systems.
• Track record of owning complex technical projects from concept through production.
• Previous experience within financial services or capital markets.

Responsibilities

• Design, build and deploy production-grade AI applications.
• Architect scalable RAG pipelines, agentic workflows and LLM-powered services.
• Build reliable AI APIs and backend services using Python.
• Drive model evaluation, prompt optimisation and AI system performance.
• Partner with engineering leadership on architecture and technical strategy.
• Mentor engineers and help establish best practices across the AI function.

Skills

Production LLMs

RAG & AI agents

Vector databases

Cloud platforms

Distributed systems

Project ownership

Tools

Python

LLM frameworks

Job description

I'm working with a well-funded capital markets technology business that's building an AI-first platform to solve complex problems across financial services. They're looking to hire a Principal AI Engineer to help shape the next generation of their AI capability.

This is a hands-on technical leadership role for someone who has built and deployed production AI systems at scale. You'll have significant influence over architecture, technical direction and the delivery of AI-powered products, while remaining deeply involved in engineering.

The role

• Design, build and deploy production-grade AI applications.
• Architect scalable RAG pipelines, agentic workflows and LLM-powered services.
• Build reliable AI APIs and backend services using Python.
• Drive model evaluation, prompt optimisation and AI system performance.
• Partner with engineering leadership on architecture and technical strategy.
• Mentor engineers and help establish best practices across the AI function.

What they're looking for

• Experience building and deploying production LLM applications.
• Strong background with RAG, AI agents and modern AI frameworks.
• Experience with vector databases, cloud platforms and scalable distributed systems.
• A track record of owning complex technical projects from concept through production.
• Previous experience within financial services or capital markets

Why it's worth exploring

• Join a business building AI at the core of its product rather than as an add-on.
• High levels of ownership and influence over technical direction.
• Solve challenging engineering problems with modern AI technologies.
• Work alongside experienced engineering leaders in a fast-paced environment.
• Competitive compensation, bonus and equity.