Lead AI/ML Engineer (P4645)

84.51˚; Chicago (IL); On-site; USD 125,000 - 207,000; Full time

Benefits offered by this job

Health insurance

401(k) with Roth option (matching)

Paid time off + holidays

Job summary

84.51° is seeking a Lead AI/ML Engineer to drive optimization-based AI solutions on the Labs team in Chicago. You will contribute code daily, mentor engineers, and partner with cross-functional stakeholders to scale production systems.

This role focuses on blending classical optimization with modern AI/ML, including CI/CD and MLOps practices, and requires strong Python and solver experience.

Qualifications

• Bachelor’s or Master’s degree in CS, ML, applied math, or related field.
• 4+ years building ML/AI/optimization systems with production deployment.
• Strong Python programming and software engineering fundamentals.
• Fluency with NumPy, pandas, PySpark and at least 3 of PyTorch, TensorFlow, scikit-learn, Pyomo.
• Experience deploying at least one optimization problem (e.g., routing, scheduling).
• Experience with at least two optimization solvers (Gurobi, CPLEX, OR-Tools, Pyomo, PuLP, CBC, SCIP).
• Experience designing CI/CD and MLOps workflows (MLflow, Azure ML, Databricks).
• Familiarity with Azure and Docker; Kubernetes.

Responsibilities

• Build end-to-end ML, AI, and optimization-based solutions.
• Design hybrid AI/optimization systems with learned components.
• Lead design, implementation, and reviews for POCs and prod systems.
• Mentor engineers and researchers; collaborate with cross-functional teams.
• Develop ML(AI)Ops pipelines for experimentation and deployment.
• Drive code quality, observability, and best practices.

Skills

Python programming

Leadership

Mentoring

Problem solving

Cross-functional collaboration

Education

Bachelor’s or Master’s degree in Computer Science, Machine Learning, Applied Mathematics, or related field

Tools

PyTorch

TensorFlow

scikit-learn

Pyomo

Gurobi

CPLEX

OR-Tools

PuLP

Docker

Kubernetes

MLflow

Azure ML

Databricks

Job description

84.51° Overview

84.51° is a retail data science, insights and media company. We help The Kroger Co., consumer packaged goods companies, agencies, publishers and affiliates create more personalized and valuable experiences for shoppers across the path to purchase.

Powered by cutting‑edge science, we utilize first‑party retail data from more than 62 million U.S. households sourced through the Kroger Plus loyalty card program to fuel a more customer‑centric journey using 84.51° Insights, 84.51° Loyalty Marketing and our retail media advertising solution, Kroger Precision Marketing.

84.51° follows a 5‑day in‑office work schedule to support collaboration, alignment, and team connection.

Join us at 84.51°!

LEAD AI/ML ENGINEER (P4645)

Summary

As a Lead AI/ML Engineer (G3) on the Labs team, you will serve as a hands‑on technical lead at the intersection of classical optimization science and modern AI/ML. Our Labs team has a strategic focus on building AI‑enhanced optimization systems, designing AI layers that augment, accelerate, and extend classical optimization engines to unlock solutions that neither approach achieves alone. This is not a generalist ML role: you will bring deep optimization foundations and use them as the platform on which the next generation of intelligent, adaptive systems are built.

You will contribute code daily, serve as one of the team's primary subject‑matter experts on optimization formulations, solver selection, and hybrid architecture design, mentor engineers and researchers, and partner with cross‑functional stakeholders to define, deliver, and scale production systems across Kroger.

Responsibilities

• Serve as a hands‑on developer responsible for building and maintaining end‑to‑end ML, AI, and optimization‑based solutions
• Design and build hybrid AI/optimization systems including ML‑guided search, learned warm starts, neural network surrogate models, and AI‑augmented constraint formulations that improve the performance, scalability, interpretability and adaptability of classical optimization solvers
• Lead technical design, implementation, and review processes for POCs and production‑ready systems
• Lead end‑to‑end solution lifecycle— from rapid prototyping through to scaling and hand‑off to production teams in partnership with other data scientists and engineers within Labs and across the business
• Serve as one of the team's primary technical resources on optimization problem formulations, solver selection, and performance benchmarking across constraint types and problem scales
• Partner with researchers and data scientists to co‑develop, scale, and operationalize new algorithms
• Architect and implement robust ML(AI)Ops pipelines that support experimentation, deployment, and monitoring
• Build reusable ML components and APIs that enable modularity and scalability across business areas
• Evaluate and adopt emerging technologies and tooling that can enhance experimentation and delivery speed
• Drive technical best practices in code quality, documentation, observability, and team knowledge sharing
• Drive experimentation and benchmarking to select performant solutions that balance complexity and business value
• Contribute to Labs’ collaborative, research‑forward culture by learning, sharing, and mentoring both junior and senior engineers and researchers on industry‑leading and cutting‑edge technologies
• Lead and participate in code reviews and technical architecture planning to ensure adherence to preferred patterns and standards
• Represent Labs in technical forums; proactively mentor junior and peer engineers
• Collaborate with product and business stakeholders to align technical execution with innovation goals

Required Qualifications

• Bachelor’s or Master’s degree in Computer Science, Machine Learning, Applied Mathematics, or a related field
• 4+ years experience experience developing ML, AI, or optimization systems, including production deployment and scaling
• Strong software engineering fundamentals and daily coding experience in Python
• Deep proficiency in Python and fluency in NumPy, pandas, PySpark and at least 3 of the following ML and Optimization libraries – PyTorch, TensorFlow, scikit‑learn, and Pyomo (Pyomo proficiency is specifically required)
• Hands‑on experience architecting and productionizing at least one type of optimization problem (e.g., network optimization, vehicle routing, scheduling, facility location, or resource allocation)
• Practical experience with at least two industry‑standard optimization solvers such as Gurobi, CPLEX, OR‑Tools, Pyomo, PuLP, CBC, or SCIP
• Demonstrated experience designing or prototyping hybrid AI/optimization systems where ML or AI components (surrogate models, learned heuristics, prediction models, AI chatbots) interact with or augment classical optimization solvers
• Hands‑on experience designing CI/CD and MLOps workflows using tools such as MLflow, Azure ML, or Databricks
• Familiarity with cloud platforms (Azure preferred), containerization (Docker), and orchestration (Kubernetes
• Experience with modern software development practices including testing, logging, observability, and version control
• Ability to lead projects through ambiguity and collaborate in highly cross‑functional teams

Preferred Experience

• Deep knowledge of operations research fundamentals such as linear programming, integer programming, mixed‑integer programming, constraint programming, stochastic optimization, or combinatorial optimization
• Experience integrating reinforcement learning, neural combinatorial optimization, or other ML‑driven approaches with classical solver frameworks (e.g., ML‑guided branching, policy‑based heuristics, or graph neural networks for combinatorial problems)
• Familiarity with applied research at the optimization/AI/ML intersection such as learning to optimize, predict‑then‑optimize, end‑to‑end differentiable optimization, algorithm selection via ML, AI assisted optimization
• Strong track record of partnering with researchers to translate early‑stage ML ideas into deployable systems
• Experience prototyping and scaling AI solutions in applied environments
• Experience designing experiment platforms or reusable ML/optimization infrastructure
• Demonstrated leadership in evaluating trade‑offs between performance, complexity, and maintainability
• Familiarity with real‑time or batch data processing systems
• Leadership in navigating trade‑offs between performance, complexity, and long‑term maintainability

Pay Transparency And Benefits

• The stated salary range represents the entire span applicable across all geographic markets from lowest to highest. Actual salary offers will be determined by multiple factors including but not limited to geographic location, relevant experience, knowledge, skills, other job‑related qualifications, and alignment with market data and cost of labor. In addition to salary, this position is also eligible for variable compensation.
• Below is a list of some of the benefits we offer our associates:
  • Health: Medical: with competitive plan designs and support for self‑care, wellness and mental health. Dental: with in‑network and out‑of‑network benefit. Vision: with in‑network and out‑of‑network benefit.
  • Wealth: 401(k) with Roth option and matching contribution. Health Savings Account with matching contribution (requires participation in qualifying medical plan). AD&D and supplemental insurance options to help ensure additional protection for you.
  • Happiness: Paid time off with flexibility to meet your life needs, including 5 weeks of vacation time, 7 health and wellness days, 3 floating holidays, as well as 6 company‑paid holidays per year. Paid leave for maternity, paternity and family care instances.

Pay Range: $125,000—$207,000 USD