Principal AI Engineer - Lead AI Platform & Architecture

Harrington Starr; Boston (MA); On-site; USD 180,000 - 240,000; Full time

Benefits offered by this job

Competitive compensation

Bonus

Equity

Job summary

Harrington Starr seeks a Principal AI Engineer to shape the next generation of its AI capability in capital markets. This hands-on technical leadership role combines architecture influence with deep engineering involvement.

You will design production-grade AI applications, build scalable LLM-powered services, mentor engineers and drive performance in AI systems, working closely with engineering leadership. Experience deploying at scale in financial services and a track record delivering complex

Qualifications

• Experience deploying production LLM applications.
• 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 LLM deployment

RAG & AI agents

LLM frameworks

Vector databases

Cloud platforms

Distributed systems

Technical leadership

Python

APIs

Tools

Python

APIs

ML tooling

Job description

Harrington Starr seeks a Principal AI Engineer to shape the next generation of its AI capability in capital markets. This hands-on technical leadership role combines architecture influence with deep engineering involvement.

You will design production-grade AI applications, build scalable LLM-powered services, mentor engineers and drive performance in AI systems, working closely with engineering leadership. Experience deploying at scale in financial services and a track record delivering complex