Ruyi C.

AI / Data Engineer πŸ‡¨πŸ‡³πŸ‡ΊπŸ‡ΈπŸ‡―πŸ‡΅ | LLM Workflows β€’ Analytics β€’ Automation | CMU MS Software Engineering

Greater Tokyo Area

About

*Check my personal portfolio here: https://portfolio-2025-cry.vercel.app/ I leverage my experience in software development, data analytics, and building AI-powered solutions to drive real business impact. Through hands-on projects in graduate school and in my current role, I have designed and operated data-driven systems using Python, SQL, cloud tools, and modern web frameworks, delivering solutions that address business challenges and improve efficiency. I quickly learn and apply new technologies in practice. Throughout my academic and professional experiences, I have gained proficiency in multiple programming languages and frameworks, allowing me to contribute effectively in development environments.

Experience

  • Data Engineer at Sales Marker Co., Ltd.
    Nov 2025 - Present Β· 9 mos

  • Global Graduate β€” Data & Analytics at BAT
    Oct 2024 - Oct 2025 Β· 1 yr 1 mo

    ● Developed and deployed unsupervised ML models (KMeans, Hierarchical Clustering, DBSCAN) to segment 30,000+ retail outlets, achieving a silhouette score of 0.43. Insights from clustering guided channel-specific trade and product assortment strategies. ● Led end-to-end development of the Promo Master platform, consolidating fragmented promo data from 9 Excel sources across 3 teams into a centralized backend and UI; reduced manual data entry by 80% and accelerated campaign setup for 100+ annual activations. ● Acted as a data analyst to bridge business goals with technical delivery; defined KPIs and delivered interactive PowerBI dashboards adopted by 300+ users with a 70%+ adoption rate.

  • Software Engineer Internship at Carnegie Mellon University
    Jan 2024 - Oct 2024 Β· 10 mos

    β€’ Developed real-time monitoring dashboards using React, JavaScript, and dynamic graph libraries. β€’ Enhanced system observability for a distributed system, enabling 30% faster issue detection. β€’ Reduced debugging time by 40% for a message queue application through dynamic visualizations.

  • Software Engineer Internship at Information Development America Inc.
    Aug 2022 - Nov 2022 Β· 4 mos

    β€’ Developed a VR application with Unity in a team of 3, focusing on multiplayer and avatar implementations using C# β€’ Tested enterprise blockchain functionalities and compiled glossaries and reports to support over 1000 engineers in understanding blockchain technologies

  • Brandeis University (10 mos)
    • Multivariable Calculus Teaching Assistant
      Jan 2022 - May 2022 Β· 5 mos

    • Computer Science Teaching Assistant
      Aug 2021 - Dec 2021 Β· 5 mos

      Teaching Assistant for Mobile App Development course