Applied AI Engineer, Computer Vision & Data Science — Boulder, CO

About 3LC

3LC illuminates the black box of Physical AI model training. We build the first full-loop platform for AI data preparation and optimization, combining labeling, debugging, diagnosis, and curation so teams can ship better, smaller, faster models.

Across energy, agriculture, manufacturing, and aerospace, machines are learning to see the physical world: inspecting wind turbines, spotting crop disease, and checking parts on a manufacturing line. They can only see as well as the data they learn from, and that data is often messy. 3LC helps computer vision teams find and fix flaws in their training data so the systems built on it see the world more clearly and reliably; all within the customer's own infrastructure.

We are a team of 14, with colleagues across Norway and the US. Backed by several leading VC firms and growing fast, we offer the opportunity to take real ownership, work closely with customers, and help shape the product.

The Role

As an Applied AI Engineer at 3LC, you’ll work directly with customers, both in and on their infrastructure, to develop and improve computer vision models using 3LC. You’ll help turn real-world challenges into well-defined machine learning problems, understand where models fail, and develop efficient processes that support their use of ML and 3LC.

You’ll work across the ML pipeline, from exploring datasets and establishing baselines, to training, evaluating, and preparing models for production. Working with customer teams, you’ll focus on delivering high-quality Computer Vision ML results, building models, integrations, plugins, and workflows that align with their goals, and making ML and 3LC an effective part of their day-to-day work. You’ll also bring what you learn back into the product, improving our Python APIs and helping shape how 3LC supports practical ML work.

This position is based in our Boulder, Colorado office and requires working on-site. Remote and hybrid arrangements are not available.

What You’ll Do

· Work directly with customer teams to understand their challenges, infrastructure, and ML processes, define effective evaluation criteria, and establish model-performance baselines.

· Develop, train, and improve computer vision models for tasks including object detection, segmentation, and classification.

· Use 3LC to explore datasets, investigate failure cases, assess labels, and identify data improvements that make a measurable difference.

· Develop efficient processes and workflows within customers’ infrastructure for data curation, training, evaluation, debugging, and monitoring.

· Build and maintain integrations, plugins, and reusable tools that connect 3LC to customers’ ML systems and infrastructure, writing clean, well-tested Python code and improving 3LC’s platform and APIs.

· Explain findings and trade-offs to customers, helping them understand what changed, why it matters, and what to try next.

· Create reusable examples, benchmarks, and documentation so lessons from one project inform the next.

· Stay current with relevant ML research and bring useful techniques to customer work and the product.

What We’re Looking For

· Strong understanding of Machine Learning concepts, model approaches, and training techniques.

· Strong Python skills and experience working in substantial codebases.

· Hands-on experience building and improving Computer Vision models with PyTorch or comparable frameworks.

· Practical experience preparing datasets, training models, evaluating results, and investigating failures.

· A thoughtful approach to experimentation, including selecting meaningful metrics and evaluating whether improvements hold up.

· An interest in data-centric AI and in how data quality, coverage, and labeling affect model behavior.

· Strong communication skills and the ability to resolve technical problems with customers.

· Initiative and follow-through, including comfort with working through ambiguity and taking responsibility for delivery.

· Ability to work on-site at our Boulder office.

Nice to Have

· Experience with real-world industrial computer vision or other applications involving challenging data.

· Familiarity with tools such as YOLO, Detectron2, SAM3, and PyTorch.

· Experience deploying or optimizing models, including ONNX or TensorRT.

· Experience with cloud ML infrastructure with a strong focus on Azure.

· Experience in customer-facing engineering, technical onboarding, or proof-of-concept delivery.

· Experience with active learning, data quality tooling, embeddings, or data-drift monitoring.

· Open-source contributions or projects that demonstrate your approach to practical ML problems.

Compensation & Benefits

· Salary range: $110,000 – $140,000 per year, depending on experience, plus meaningful equity.

Benefits include:

· Health, dental, and vision insurance.

· 401(k) retirement plan.

· Paid time off (15 days / 3 weeks) plus company holidays.

· Equity / stock options

This is a full-time, exempt position.

Why 3LC?

You’ll work closely with the people building the product and the teams using it. Your work will help customers solve real ML problems while directly informing what we build next.

We’re a small team across the US and Norway, with room to contribute ideas, take ownership, and see your work through.

How to Apply

Send your CV, a short note and a few examples of your work, infrastructure you've built, models you own, repos, or write-ups that show how you think, to ••••••••.

Applications are reviewed on a rolling basis. This posting will remain open until the position is filled.

No recruiters, please. We review every application personally.