Full-Time Machine Learning Engineer (LLM/GenAI)

Team’s Mission / Work Responsibilities

The AI / LLM Team’s mission is focused on two core pillars, "building" and "enabling" – delivering new AI-driven features and user experiences to maximize the impact of Mercari's business, as well as utilizing AI technologies to enhance productivity across the entire Mercari Group. We do this both through independent initiatives owned by our team, as well as by horizontally collaborating with product and engineering teams across the entire organization

(Learn more about Mercari's mission and values here.)

As a machine learning engineer, you will work on ML architecture and feature engineering that touches all parts of the business as well as internal tooling.

Specific work responsibilities include the following:

• Develop and Optimize ML Models: Design, build, and optimize machine learning models to solve complex problems and perform specific tasks. Focus on optimizing model performance and scalability to handle large-scale production systems.
• Feature Engineering: Conduct in-depth feature engineering to improve the robustness and accuracy of ML models, particularly in the context of natural language processing (NLP), computer vision, and multimodal learning.
• Model Deployment and Integration: Collaborate with cross-functional teams to integrate ML solutions into existing products and services, ensuring seamless deployment and operational efficiency.
• Research and Innovation: Keep up-to-date with the latest research and advancements in AI and machine learning, and related fields such as NLP and computer vision.
• Engineering Infrastructure: Design engineering infrastructure to support machine learning systems at scale.
• Experimentation and Testing: Conduct A/B testing, experiments, and evaluations to assess the performance and impact of ML models, using insights to inform further iterations and improvements.

Unique and Bold Challenges

• In this position, you will develop AI-driven solutions that leverage Mercari Group’s vast data assets, creating high-impact user experiences for tens of millions of users.
• Work at the intersection of cutting-edge research and practical application, translating state-of-the-art AI/LLM developments into tangible business solutions.
• Engage with diverse teams to build and refine large-scale ML infrastructure and systems.

Required Qualifications

• Shared belief in the mission and values of Mercari Group and its various companies.
• Bachelor's degree in Computer Science, Engineering, or a related technical field, or equivalent practical experience.
• Proficiency in Python and experience with ML frameworks such as PyTorch or TensorFlow. Strong understanding of architectural patterns for large-scale software applications.
• Demonstrated experience in the end-to-end ML lifecycle, from development to deployment.
• Strong analytical skills with the ability to solve complex, unstructured problems.
• Excellent written and verbal communication skills, with the ability to explain technical concepts to non-technical stakeholders.
• Passion for the products and technologies.

Preferred Qualifications

• Experience with deploying AI solutions in large-scale production environments.
• Master’s or Ph.D. degree in Computer Science, AI, ML, or a related technical field.
• Background in generative AI, LLM, and natural language processing (NLP).
• Experience in multilingual and multimodal models, reinforcement learning, and efficient training and inference techniques.
• Participation in the open-source community and contributions to AI/ML projects.

Screening Criteria

• Has leadership ability, flexibility, and time management skills
• Proactively learns new technologies and puts them into practice
• Thinks about what’s best for the product and how they can provide the most value through technology
• Sees diverse changes as opportunities for constant improvement and development
• Is able to consistently come up with ideas for improvement and act upon them
•  (See this page for details.)

Language Requirements

• Either of the following is required:
• English: Independent (CEFR - B2)
• Japanese: Independent (CEFR - B2)
  *Check here for more information about CEFR.