Senior Java / Machine Learning Engineer

Title: Senior Java / Machine Learning Engineer (Supply Chain & Fulfillment)
Overview
We're hiring a Senior Java / ML Engineer to build intelligent systems that power demand forecasting,
inventory optimization, routing, and fulfillment in a large-scale retail environment. This role
bridges backend engineering and production ML, turning models into real-time decisioning
systems used across distribution centers and eCommerce platforms.
You'll work with high-volume data and partner with product, data science, and operations to deliver
systems that directly impact in-stock rates, delivery speed, and cost efficiency.
Responsibilities
 Design and build Java-based microservices (Spring Boot) real-time inference
 Productionize ML models for forecasting, recommendations, and optimization
 Build data pipelines for training and inference (batch + streaming)
 Expose models via REST/gRPC APIs and integrate into operational systems (WMS, order
routing)
 Optimize for latency, throughput, and reliability in distributed systems
 Implement monitoring (model drift, accuracy, latency, failure modes) and retraining strategies
 Partner with DS to choose between heuristics vs classical ML vs LLM/agentic approaches
 Contribute to CI/CD and DevOps for ML systems
 Participate in architecture decisions and mentor engineers
Required
 5–8+ years in software engineering with strong Java
 Experience with Spring Boot and microservices
 Hands-on experience integrating ML into production systems
 Strong systems design (APIs, distributed systems)
 Working knowledge of Python for ML workflows
 Solid SQL + experience with large-scale data
 Cloud experience with Google Cloud Platform, Amazon Web Services, or Microsoft Azure
 Docker + Kubernetes
 Comfortable operating in ambiguous, high-impact environments
Preferred
 Experience with Kafka / PubSub
 MLOps tooling (MLflow, Vertex AI)
 Experience with forecasting, inventory, routing, or pricing
 Exposure to LLMs, RAG, or agent-based systems
 Experience in retail, supply chain, or logistics
Ideal Profile
A backend-heavy engineer who has successfully shipped ML-powered services and understands
tradeoffs between heuristics, ML, and AI systems in real-world operations.

Marathon TS is committed to the development of a creative, diverse and inclusive work environment. In order to provide equal employment and advancement opportunities to all individuals, employment decisions at Marathon TS will be based on merit, qualifications, and abilities. Marathon TS does not discriminate against any person because of race, color, creed, religion, sex, national origin, disability, age or any other characteristic protected by law (referred to as "protected status ").