Built end-to-end international cold outreach system covering 20,000+ verified contacts across US/Europe/Asia, achieving 40%+ open rate with 80% process automation through integrated workflow (Google Sheets automation, Mailchimp, Hotjar analytics). Established AI system quality evaluation framework for audio processing pipeline using LLM-as-Judge and batch API optimization across 30+ iterations. Developed AI-powered invoice automation using OpenAI Assistants API, reducing monthly expense reporting time from several hours to ~30 minutes (≈90% time savings). Collaborated with French supervisor on international market research and exhibition preparation, coordinating visual design, website content management, and digital marketing campaigns.