Senior Machine Learning Engineer (Research Team)

GR8 Tech builds the B2B platforms for major iGaming operators. They are growing their AI/ML Research Team and need a Senior Engineer to lead the charge on Personalization and Discovery. Your primary mission is to build a large-scale Two-Tower Recommendation System deployed on AWS. This is not a "train and forget" role; you will own the retrieval, ranking, and evaluation pipelines that serve millions of users.

Key Responsibilities

• RecSys Architecture: Design and evolve two-tower / embedding-based retrieval models and downstream rankers.
• Model Development: Train and improve models using Deep Learning (PyTorch/TensorFlow) and Classical ML (XGBoost/LightGBM).
• Production Engineering: Optimize models for latency and cost, deploying them in real-time or batch workflows on AWS.
• Experimentation: Design and analyze offline experiments and online A/B tests to measure business impact.
• Mentorship: Act as a technical mentor for other ML engineers.

Requirements

• Experience: 5+ years in Applied Machine Learning or Data Science.
• Core Stack: Strong Python skills with proficiency in PyTorch or TensorFlow.
• Algorithms: Practical experience with Embedding Models, Similarity Search, and Tree-based models (LightGBM/XGBoost).
• Production: Experience deploying ML models in production environments (Docker, Linux, CI/CD).
• Math/Stats: Strong understanding of applied statistics and ML evaluation metrics.

Nice to Have

• Vector Search: Familiarity with ANN (Approximate Nearest Neighbors) methods like FAISS.
• Architecture: Experience specifically with Two-Tower / Dual-Encoder architectures.
• Optimization: Experience with hyperparameter optimization tools like Ray Tune or Optuna.

Benefits

• Remote-First: Work from anywhere + Coworking compensation.
• Benefits Cafeteria: Annual budget for Sports, Medical, or Mental Health.
• Leave: Unlimited Sick Leave, Paid Parental Leave, and 20+ Vacation Days.