People

After engaging in data analysis and logic development and operation at an information curation service company, Hiroaki joined Merpay, Inc. in 2018, focusing on the design and development of credit models centered around machine learning/natural language processing, and the development of machine learning models and systems in the fraud detection domain. Since April 2023, he hasbeen part of a team aiming to challenge new technologies such as large language models (LLM).

Abhijeet joined Mercari as a new graduate in 2019 and is currently working as a ML engineer on the Data Science Backend Team—a team with a unique intersection of responsibilities. While Abhijeet and his team provide data science support to backend teams to help them develop better personalized services, they also provide backend support to ML teams, assisting them in the development, deployment and maintenance of the services that support their ML models. Through this work, Abhijeet has developed a diverse skill set in ML as well as backend development. Abhijeet is also the scrum master of the team.

As an ML Engineer, Andre primarily contributes by integrating deep learning and NLP techniques, including large language models, into products designed to boost productivity and optimize user experience. Holding a PhD in Engineering with a focus on applied NLP, he utilizes a comprehensive range of research and engineering skills toward practical production.

Ankur joined Mercari in October 2019 as a Software / ML Engineer. He has worked on developing both ML models and the backend systems required to deploy them. Ankur has also worked on analyzing and improving the effects of Online Experiments in the marketing domain.

Anri is a Senior Software Engineer and Engineering Manager with 22 years of experience in full-stack web development, search engines, databases, startups, building SaaS products, and hiring and mentoring engineering teams. He joined Mercari in early 2021 and currently manages two search teams: Search Middleware and Search Infra.

Formerly an Assistant Professor at Saitama University, Antony made the move to industry by joining Mercari in May 2019. His experience in academia was primarily in Computer Vision (recognition, physics-based vision) and he also did some ML for neuroscience. At Mercari, he conducts R&D while employing a wide range of ML approaches for Computer Vision, Clickthrough Data, and Data Mining. At Mercari, he has contributed to both product development and academia. Feel free to check out his Google Scholar profile here.

Anupam joined Mercari in 2022 as an engineering manager in the Recommendation Team, which focuses on leveraging machine learning to improve the product discovery experience for users. Before joining Mercari, he had experience in developing and deploying deep learning models for search quality improvement, as well as leading development of data platforms for solving MLOps use cases. He is passionate about continuous process improvement and adopting quality-driven development paradigms in agile environments.

Having experience in both Machine Learning and Software Engineering, he contributes to ML projects end to end from the initial exploratory data analysis, to the ML modelling and the eventual productionalization and online business impact evaluation. In terms of Machine Learning he has used deep learning techniques to perform both Image Recognition tasks to help our customers list items more easily and Natural Language Processing tasks to enrich and understand our item data better.

Bosco started out as an astrophysicist and later joined the industry to become an ML Engineer. He is experienced in computer vision and fraud detection. At Mercari, he focuses on providing ML solutions for item moderation and other trust and safety (TnS) quests, as well as managing the tech stack of the TnS ML Team. He also owns and maintains several open-source projects related to computer vision on GitHub.

Chica has worked as a game programmer and AI development consultant before joining Mercari. She has experience working as an MLOps Engineer for AI services, and currently works on EdgeAI technology to bring AI working on low-spec devices such as smartphones.

Chingis is a Data Scientist and an Engineer at Mercari working on search relevancy projects and solving problems in various domains, including Learning-to-Rank and NLP. He is also a researcher and technical writer with an interest in self-supervised, multimodal, and representation learning.

Deddy is a ML Engineer who joined Mercari as a new graduate. He is responsible for analyzing marketing campaigns using statistical models and mathematical optimization. On top of predicting which users respond positively or negatively to campaigns, Deddy also provides detailed explanations for those behaviors. He then shares those insights with stakeholders to discuss ways to improve future campaigns.

Henning is an ML engineer with a background in Fintech and Fraud Risk. He is currently working on ML methods to ensure trust and safety on the Mercari platform, ranging from item moderation to account takeover detection. He combines both business unit economics/analytics driving products and ML solutions to maximize business value.

Jie joined Mercari as a ML Engineer in 2019. Her work is to support marketing strategies by Machine Learning to meet customer satisfaction and make marketing efforts efficient. Currently she is working on optimizing coupon distribution strategies by applying uplift modeling. Her research domain was computer vision at her master stage and she published papers on CVPR and ICCV. Check out her google scholar page here.

Keisuke is a Software and ML Engineer with experience in financial modeling and recommendation engine development at web companies and Fintech startups. He is currently involved in multiple teams as an Engineering Manager. He is and was also involved in the development of OSS for deep learning frameworks and hyperparameter optimization, and as an evangelist, he strives to popularize the libraries.

Kenta joined Mercari in September 2018 as a Tech Lead for the Backend teams and currently Engineering Manager at Customer Reliability Engineering Camp. At the team, he is managing a feature team where Backend and ML Engineers belong. Before Mercari, he worked as a full stack engineer in the US and Japan for more than 10 years.

After working as an analytics consultant, Koya joined Mercari in 2022. As a marketing data scientist at Mercari, he analyzed marketing measures using machine learning and statistical models. He is currently working on measures related to improving customer satisfaction, and is responsible for a wide range of tasks from project design to implementation and evaluation.

Kumar joined Mercari as a new graduate in 2018. He started out as a ML Engineer on the Image Search Team and then moved to the Data Science Backend Team where he is currently working as an Engineering Manager & Tech Lead. Kumar’s team focuses on providing a personalized experience to Mercari’s users through ML along with developing backend solutions to scale the use of data science. In addition to his interests in ML and backend development, Kumar also enjoys formulating efficient, agile processes within the engineering teams.

Lirong is a dedicated ML Software Engineer specializing in Search Team operations. Her expertise lies in utilizing ML models like LLM for enhancing query quality through synonym expansion and query rewriting. She has also been involved in establishing an offline evaluation pipeline, defining metrics, and implementing relevance judgment during search feature development. With a constant zeal for tackling new challenges, she looks forward to leveraging her skills for our shared goals.

Masaki joined Mercari in 2022. He has experience in development of search engines from scratch and personalization of ads using bandit algorithms. He is currently working on the Recommendation Team to improve the user experience on Mercari’s home screen and item details screen.

Mohit is a Software Engineer and Data Scientist with experience in building ML systems and improving Mercari’s experimentation practices. He is currently working as a search engineer, scaling Mercari’s search features and improving search efficiency. Prior to that, Mohit worked on projects related to pricing and influencing user pricing behavior. He was a core member of the team responsible for building the multi-armed bandit system for pricing.

Naoki joined Mercari in 2023 as a new-graduate ML Engineer. Currently, he is working on optimizing customer support operations using machine learning. He has experience in developing skeletal estimation from images and disease prediction from pathological images, and has been a top ranker in competitions in the field of computer vision while conducting research in the field of Vision & Language at university and graduate school.

Naoya joined Mercari in 2022 as a ML Engineer. As a member of the Recommendation Team, he strives to improve the user experience on Mercari’s home screen. Before joining Mercari, he worked as a data scientist in charge of developing features using analytics and machine learning in an automotive business. He is a Kaggle Master and occasionally participates in competitions.

Pablo is a Data Scientist and Engineering Manager in the ML Price Team, currently focusing on helping our users to successfully sell their items in Mercari. Other than price he has worked around data related topics and features such as Image Search. Before joining Mercari he was working as a Deep Learning Researcher in the field of edge AI, where he investigated quantization, compression, and other techniques in order to bring computer vision models into FPGAs. Before that he worked in the gaming industry as a Data Scientist, focusing on behavioral analysis, monetization, and data design.
He is first and foremost passionate about data: from behavioral analysis to online experimentation and optimization, going through all steps in the data generation process such as schema definition.

Prashant joined Mercari in 2019 as an ML Engineer and works with inquiries Mercari receives from users. He leads the development of ML services that help in reducing the time it takes customer support agents to respond to inquiries and the resources spent on customer support operations. Although he is good at working with production ML systems, allegedly, some say he is way better at making pour-over coffee.

After working for an AI startup and an e-commerce company developing ML models using natural language and tabular data, Rintaro joined Mercari in June 2022, where he is involved in improving the operational efficiency of the customer support team as an ML Engineer. Currently, he is in charge of the process for recommending the best response template for user inquiries, covering all steps from modeling to effectiveness verification and product implementation.

Ryan is a Software and ML Engineer with experience in MLOps at several startups. He is currently working in the Item Understanding Team as Tech Lead, and most recently as temporary Engineering Manager.

Ryo joined Mercari in 2020. As a software engineer, she has experience developing content moderation and recommendation systems using machine learning. Currently, he is the Tech Lead of the Recommendation Team, working to improve the user experience through personalization.

Shanshan is an ML engineer with background in Search Engine and Advertisement Recommendation. Currently, she is dedicated to building advanced ML models to enhance the user experience, ensuring they can effortlessly find the items they seek. Her passion lies in leveraging technology to optimize search functionality and create a personalized search journey for users.

QIAN is a Software and ML Engineer in Mercari search team. He mainly focuses on search quality evaluation, search relevancy improvement and query intent understanding. As a ML Engineer, he uses different ML algorithms (GBDT, BERT, and etc.) to model user behaviors and seek possibilities of improving search quality. Basically he is working on all tasks of the search A/B experiment pipeline: Modeling -> Implementation -> AB test -> Data analysis and judge -> Release.

Shinya joined Mercari in 2020. As a data analyst, he worked on workflow improvement related to A/B testing and analysis to improve personalization features. Currently, he is in charge of personalization feature development as an ML Engineer.

Shunya has extensive experience developing recommendation engines and graph mining engines in a social platform, as well as adtech and marketing data development using natural language processing. Since 2017, he has been the Director in areas around Artificial Intelligence and Search Engines at Mercari.

Aman is a software and MLOps engineer working in Mercari since 2018 with experience in designing solutions and deployment pipelines for machine learning applications on cloud.
He has a keen interest in open-source tools and building ML platforms using them. He is currently working on improving the ML platform at Mercari and increasing developer productivity.

Subodh is a passionate software engineer with experience in ML infrastructure, CI/CD, production microservices, and Kubernetes. He is currently involved in improving Mercari’s ML platform for multiple ML teams to provide seamless ML training, serving, monitoring, and more on the platform. While building the ML platform, he contributed to the Kubeflow open-source software for improvements in its deployment process and used it in Mercari to benefit from multiple open-source and in-house services, all in one place.

After gaining experience in developing and operating ML models in the marketing domain, Takuma joined Mercari in 2022 as a Software Engineer. Currently, he is working on improving the search experience by re-ranking search results using machine learning.

Teo is an accomplished ML Engineer currently working within Mercari’s AI & Search division. His primary focus is on architecting and implementing highly scalable and resilient ML systems to significantly enhance search relevancy for Mercari’s over 20 million monthly active users. In addition, Teo plays a crucial role in spearheading the establishment and continuous improvement of foundational cross-team MLOps platforms, workflows, and engineering guidelines across Mercari.

Tomohiro majored in Library and Information Science in graduate school and has been working on product development for information retrieval and recommendation since graduation.
He joined Mercari in May 2019, worked on prototype development of search evaluation and recommendation systems.Then, he launched the recommendation team and is currently a product manager driving development that improves the overall discovery experience.

Yilin is a ML Engineer at Mercari Japan and is a member of the Marketing Data Science Team. Her background is in applying modeling, mathematical optimization, and other techniques to marketing strategies. she has experience in designing solutions to improve profit by integrating ML and mathematical optimization, as well as analyzing user behavior to improve user engagement through personalized communication.

Yusuke worked on improving ad delivery algorithms and setting up data infrastructure at an internet advertising company, as well as on development of a speech recognition product at an AI startup, before he joined Merpay in 2021. He was transferred to Mercari in 2022 and is currently involved in feature enhancement and maintenance of Mercari’s ML platform.

Since joining in 2019 Yusuke has been working on a Machine Learning model and backend development in the Customer Reliability Engineering field, such as violation detection systems. Since then he now handles data analysis and implementation for a team that finds tasks and develops solutions in quick iterations. He has been part of a research and development startup while still in school, and is good at coming up with solutions for difficult problems and tasks.

Yuta joined Souzoh in 2022. In his previous company, he gained experience in developing data analysis platforms and ad serving platforms based on click and purchase prediction. At Souzoh, he was in charge of developing functionality for B2C item recommendations and searches. Currently, he has moved to Mercari and is working on improving the user experience on the home screen and item details screen as part of the Recommendation Team.

Having gained experience in large-scale system development and data science consulting at an IT services company, Yuhi joined Merpay as an ML Engineer in 2019. After joining, he has been responsible for developing and operating credit models and their systems, and as a graduate student, he is also engaged in research activities in the field of machine learning.

In 2021, Takuya participated as an intern in the online program “Build@Mercari.” After graduating from graduate school, he joined Merpay as a new graduate ML Engineer in 2023. Currently, he belong to the Credit Modeling team, where we calculate credit scores based on usage history on Mercari. He is involved in the operation and development of credit scores and collection models.

After engaging in system development for financial institutions, machine learning, and data science consulting, Hiroshi joined Merpay as a ML Engineer in 2021. Currently, He is working as an Engineering Manager, focusing on the development and management of credit models.

After engaging in internships at IT companies and conducting research on information recommendation in graduate school, Yuya joined the Credit Modeling team at Merpay as a new graduate in 2022. Currently, he is involved in the operation and development of credit models.

ML engineer with a background in spatiotemporal series prediction, deep learning, and MLOps. Calvin has experience in various ML projects, both in academic and industry, ranging from weather prediction and image classification to market analysis. He is currently tackling diverse fun engineering and data science problems inside an ML team that ensures the trust and safety of Mercari/Merpay platform.

Since joining Merpay in 2020, Ayato has been working in the Trust and Safety (TnS) domain as a ML Engineer, focusing on creating fraud prevention solutions related to accounts and transactions.

After gaining experience in data analysis and modeling across a wide range of industries as an Analytics Consultant, Shuji joined Merpay in 2021. Following the development and operation of models in the credit and fraud detection domains, he is currently working on the use of machine learning in the application of LLM and the growth domain.