AI/ML Engineer

Luster is a cutting-edge AI Practice and Predictive Enablement™ platform that helps sales teams close skill gaps before they impact performance. By utilizing hyper-realistic AI simulations and real-time skill insights, Luster empowers sales reps to master key techniques like objection handling and discovery. Backed by High Alpha, Luster creates tailored practice environments with custom customer personas, ensuring sales teams consistently perform at their best.

Job Summary

We’re looking for a talented AI/ML Engineer to drive innovation in how we deliver realistic, adaptive simulations and predictive insights. This role will focus on building and fine-tuning large language models (LLMs), designing intelligent dialogue systems, and developing recommendation engines that personalize coaching and practice experiences.

You’ll work cross-functionally with our product, engineering, and customer teams to push the boundaries of what’s possible with conversational AI and intelligent skill development.

If you’re passionate about LLMs, reinforcement learning, data science, and building ML-powered products from scratch—this is your opportunity to shape the core of an emerging AI category.

Key Responsibilities

LLM Development & Fine-Tuning:

• Design, fine-tune, and evaluate large language models (OpenAI, Anthropic, Hugging Face, etc.) to power realistic, role-based AI conversations.
• Build prompt frameworks and dynamic chaining mechanisms to ensure contextual, natural back-and-forth dialogue.
• Experiment with few-shot learning, embeddings, and personalization techniques for character and scenario simulation.

AI-Powered Recommendation Systems:

• Design and implement intelligent recommendation systems that suggest personalized practice paths and coaching interventions based on behavior and performance.
• Leverage behavioral data to identify skill gaps and automatically surface content, prompts, or simulations.

Data Science & Insights:

• Analyze user interaction data to extract insights on skill development, conversation quality, and coaching effectiveness.
• Build models to predict user outcomes and generate real-time performance insights.
• Support the creation of performance dashboards and reporting tools for end users and admins.

Collaboration & System Integration:

• Partner with product and engineering teams to integrate ML models into production applications with reliability and scalability.
• Design and document data pipelines and model APIs.
• Stay up to date with the latest research in NLP, LLMs, and applied machine learning—and bring those innovations into our product.

Qualifications

Experience:

• 4–7 years of experience in machine learning, applied AI, or NLP-related roles
• Hands-on experience fine-tuning and deploying LLMs (e.g., GPT, Claude, LLaMA, Mistral, etc.)
• Proven track record of building and shipping ML-powered features in production
• Experience with recommendation systems and personalization models

Technical Skills:

• Proficiency with Python and ML/NLP frameworks (e.g., PyTorch, Hugging Face, LangChain, OpenAI SDKs).
• Strong understanding of ML workflows including data prep, feature engineering, model training, and evaluation.
• Experience with embedding models, vector databases (e.g., Pinecone, Weaviate), and prompt engineering.
• Familiarity with ML infrastructure tools (e.g., MLFlow, SageMaker, Vertex AI, Bedrock) and the ability to provision necessary resources within cloud infrastructure.

Soft Skills:

• Strong problem-solving skills and a detail-oriented approach to writing high-quality code.
• Excellent communication skills and ability to collaborate effectively with cross-functional teams.
• A proactive mindset with a passion for continuous learning and improvement.

• A creative and experimental mindset with a proven history of using new technologies and techniques to enhance processes and improve quality.
• Comfortable in a fast-paced, ambiguous startup environment.

Preferred Qualifications

• Experience building dialog agents or conversational AI systems.
• Background in reinforcement learning or active learning.
• Familiarity with MLOps practices and deploying models at scale.
• Experience working with product-led teams in an early-stage SaaS company.

Why Join Us?

• Opportunity to work with cutting-edge technologies and influence the technical direction of the company.
• Collaborative and inclusive work environment.
• Competitive salary, benefits, and career growth opportunities.

Compensation: $180,000-$200,000, based on experience and qualifications.

Our Values

Brilliantly Compassionate

True brilliance shines brightest when it's fueled by compassion. Our team is dedicated to creating a culture of empathy and support, where everyone's brilliance is valued and celebrated. No matter who you are — our team members, customers, users, the community — we treasure your well-being because we are bonded by connections that shine with authenticity.

Venturing from the Box

Forget outside the box. To us, there are no boxes. We value and seek creative ideas and how to push what’s achievable. We celebrate ideas that are past known constraints and goals that envision what the future could be. We dream big to illuminate the path to brilliance. To reinvent what is possible.

Honoring Expertise

The art of practice is embedded in our DNA. Like our customers, our team members are dedicated to perfecting their skills to become masters of their craft. We know we’ll always be learning, but we’ll also always strive to outpace others. Our competence and expertise will always be what allows us to outshine the competition and win the race. We celebrate the strengths and skills of everyone from our users, customers, and team members. Our goal is to make everyone an expert in their job by utilizing their skills and infusing practice into their every day.

We Face Fear Together

Our days are filled with doubt and fear. We are doing big, scary things on the cutting edge of technology – we should be scared! We value fear for being a great equalizer and know it puts us in the position to support one another. We also know change begins with the right action in the face of fear. Just like a diamond in the rough, we know there is opportunity on the other side. Fear is not a barrier. It is a motivator for action. We’re not afraid to fail — we’re afraid of not trying.

Luster is an equal-opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees.