Summary
Fumio Sagawa is a Tokyo-based founder and engineer with 13 years of experience building web applications and production-ready AI systems. As CEO and lead engineer at アシラス株式会社 since 2016, he specializes in translating vague requirements into stable semantic contracts using structured prompts, JSON schemas, evaluation loops, and Efficient Prompting layers. He practices Multi-AI Driven Development (MADD), designing redundancy-first multi-agent orchestration and drift mitigation pipelines to ensure reliable, collaborative software creation. With an M.S. in Mathematical Physics, he brings rigorous quantitative thinking to pragmatic engineering and prompt design. Bilingual in English and Japanese, he is open to AI and web engineering collaborations and focuses on preventing meaning drift in real-world deployments. A less obvious strength is his emphasis on auditable semantic contracts—making AI behavior interpretable and verifiable across development lifecycles.
13 years of coding experience