Senior Machine Learning Engineer

Harnham; Philadelphia (Philadelphia County); Remote; USD 180,000 - 200,000; Full time

Job summary

Join a fast-growing AI startup focused on digital advertising as a Senior Machine Learning Engineer. In this remote-first role, you'll lead the development of large language model applications, optimizing performance and delivering scalable solutions. Collaborate with a small, empowered team to create innovative AI tools that enhance campaign efficiency while ensuring data transparency. This opportunity offers competitive compensation, unlimited PTO, and support for professional growth in a dynamic environment where your contributions will have a significant impact.

Benefits

Unlimited PTO

Flexible work hours

Support for continuing education

Two company off-sites per year

Qualifications

• Proven experience in machine learning and AI fields.
• Deep knowledge of LLMs and related libraries.

Responsibilities

• Design and deploy machine learning solutions using LLMs.
• Optimize embedding processes and monitor model performance.

Skills

Machine Learning

AI

LLMs

Performance Monitoring

Object-Oriented Programming

Predictive Modeling

Education

Master’s in Computer Science

PhD in Statistics

Tools

AWS

Databricks

Snowflake

Hugging Face

Job description

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This range is provided by Harnham. Your actual pay will be based on your skills and experience — talk with your recruiter to learn more.

Base pay range

$180,000.00/yr - $200,000.00/yr

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Connecting Top AI and Machine Learning Talent @ Harnham NYC

Location: Remote-first (with ~5 hours overlap with US Eastern Time)

Compensation: $200k base + equity + performance bonus

A fast-growing AI startup in the digital advertising space is looking for a Senior Machine Learning Engineer to lead the development and optimization of large language model (LLM) applications. This company is building transparent, customizable AI tools that allow advertisers to retain full control over their data while improving campaign efficiency across platforms. The company is NYC-based, but the technical teams are fully remote.

This is a unique opportunity to join a small, empowered technical team with a high degree of ownership, real impact, and no corporate red tape. Backed by a major global agency partner, the company is rapidly expanding and applying LLMs to uncover patterns in unstructured data, automate insights, and enable real-time optimization.

Key Responsibilities

1. Design, build, and deploy machine learning solutions leveraging LLMs and foundational models
2. Optimize embedding processes and reduce model runtime
3. Work with large-scale systems to deliver scalable, production-ready solutions
4. Run experiments and monitor model performance in live environments
5. Utilize cloud tools such as AWS, Databricks, and Snowflake for deployment and ML lifecycle management

In the First 90 Days

1. Build predictive models using demographic and behavioral data
2. Consolidate embedding pipelines and streamline performance
3. Significantly improve model efficiency and deployment workflows
4. Contribute to the next generation of LLM-powered features

Ideal Candidate Profile

• Proven industry experience in machine learning, AI, or related fields
• Master’s or PhD in Computer Science, Statistics, or similar
• Deep experience with LLMs, foundation models, and libraries like Hugging Face
• Skilled in writing production-level code, with experience in performance monitoring and testing
• Proficient in object-oriented programming and working with APIs (REST, GraphQL, gRPC, etc.)
• Background in large-scale system development is essential
• Previous exposure to advertising or mentoring junior engineers is a plus

The Company Offers

• Remote-first setup with flexible work hours
• Competitive compensation: $200k base + equity + performance bonus
• Unlimited PTO
• Support for continuing education and professional growth
• Two company off-sites per year

How to Apply

If this opportunity sounds interesting, and you fit the above requirements, send your resume to Virginia via the Apply link on this page.

Keywords:

LLMs | Foundation Models | Hugging Face | Embedding Optimization | Neural Networks | AWS | Databricks | Snowflake | Scalable Systems | Distributed Systems | GraphQL | REST APIs | gRPC | Model Deployment | Model Monitoring | MLOps | Predictive Modeling | Unstructured Data | Behavioral Data

Seniority level

• Mid-Senior level

Employment type

• Full-time

Job function

• Industries

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