Senior Machine Learning Engineer

Groupon is a marketplace where customers discover new experiences and services everyday and local businesses thrive. To date we have worked with over a million merchant partners worldwide, connecting over 16 million customers with deals across various categories. In a world often dominated by e-commerce giants, we stand out as one of the few platforms uniquely committed to helping local businesses succeed on a performance basis.

Groupon is on a radical journey to transform our business with relentless pursuit of results. Even with thousands of employees spread across multiple continents, we still maintain a culture that inspires innovation, rewards risk-taking and celebrates success. The impact here can be immediate due to our scale and the speed of our transformation. We're a "best of both worlds" kind of company. We're big enough to have the resources and scale, but small enough that a single person has a surprising amount of autonomy and can make a meaningful impact.

Grow as a developer by building things that help local businesses around the world thrive

Are you a passionate, energetic and technology enthusiast eager to work at a rapid pace with the flexibility to work across our suite of technologies? Are you a problem solver; someone who enjoys debugging code, resolving issues, and creating solutions for common problems?

Groupon is an experiences marketplace that brings people more ways to get the most out of their city or wherever they may be. By enabling real-time mobile commerce across local businesses, live events and travel destinations, Groupon helps people find and discover experiences––big and small, new and familiar––that make for a full, fun and rewarding life. Groupon helps local businesses grow and strengthen customer relationships––resulting in strong, vibrant communities. Even with thousands of employees spread across multiple continents, we still maintain a culture that inspires innovation, rewards risk-taking and celebrates success.

Our team is responsible for maintaining and developing Groupon's recommendations engine, ensuring personalized and relevant experiences for users. We optimize algorithms, enhance system performance, and support integration with external recommendation engines for specialized use cases, continuously improving recommendation quality through data-driven insights.

We’re looking for an experienced Senior Machine Learning Engineer to help design and build a next-generation recommendation engine from the ground up. This is a high-impact role where you'll work at the intersection of architecture, algorithms, and data infrastructure—shaping the technical foundation of a system that will power personalized user experiences at scale.

You’ll collaborate with product, data, and engineering teams to define the architecture, drive model development, and implement robust pipelines that enable real-time, intelligent recommendations.

What You’ll Do:

• Design and implement a scalable architecture for recommendation systems using modern ML frameworks and distributed systems.

• Build and deploy machine learning models for ranking, retrieval, and personalization.

• Lead the development of model training and inference pipelines, with a focus on performance, modularity, and observability.

• Evaluate, experiment with, and iterate on algorithms using offline metrics and online A/B testing.

• Work closely with engineering teams to integrate models into production systems with robust CI/CD and monitoring.

• Provide technical mentorship and contribute to shaping long-term ML strategy.

  
  

What We’re Looking For:

• 8+ years of experience in machine learning, with a focus on recommender systems, ranking, or personalization.

• Proven experience designing production-grade ML architectures and infrastructure.

• Strong programming skills in Python or a similar language; familiarity with Java or Scala is a plus.

• Experience with ML libraries and frameworks (e.g., TensorFlow, PyTorch, XGBoost, LightFM, etc.).

• Solid understanding of data engineering principles (ETL, feature stores, data versioning).

• Hands-on experience with cloud platforms (GCP) and containerized deployments (e.g., Docker, Kubernetes).

• Familiarity with search engines (e.g., Elasticsearch, Solr) and their integration with ML systems is a plus.

  
  

Bonus Points For:

• Experience scaling real-time recommendation systems to millions of users.

• Familiarity with embedding techniques, deep learning for recommendations (e.g., two-tower models, transformers), or reinforcement learning.

• Background in experimentation platforms or online testing frameworks.

Groupon is an AI-First Company
We’re committed to building smarter, faster, and more innovative ways of working—and AI plays a key role in how we get there. We encourage candidates to leverage AI tools during the hiring process where it adds value, and we’re always keen to hear how technology improves the way you work. If you’re passionate about AI or curious to explore how it can elevate your role—you’ll be right at home here.

Groupon’s purpose is to build strong communities through thriving small businesses. To

Beware of Recruitment Fraud: Groupon follows a merit-based recruitment process without charging job seekers any fees. We've noticed an increase in recruitment fraud, including fake job postings and fraudulent interviews and job offers aimed at stealing personal information or money. Be cautious of individuals falsely representing Groupon's Talent Acquisition team with fake job offers. If you encounter any suspicious job offers or interview calls demanding money, recognize these as scams. Groupon is not responsible for losses from such dealings. For legitimate job openings (and a sneak peek into life at Groupon), always check our official career website at Groupon Careers