Tobias Koppers from Vercel TurboPack team discusses implementing persistent caching for long-term web application development, foreseeing significant growth in application sizes over the next decade. AI's role in code writing, TurboPack's vision for instant builds, challenges in build control, and the shift to incremental performance with caching for faster builds. TurboPack emphasizes making incremental builds fast and every build incremental, focusing on trustable and granular incremental builds, efficient granular cache handling in TurboEngine, and automatic granular cache invalidation. The system optimizes performance through efficient persistent cache integration, graph state persistence, database optimization, custom persistent layer creation, and optimizing build time efficiency. TurboPack stands out with its unique bottom-up caching approach, expansion to a general purpose bundler, and plans to enhance framework compatibility. Additionally, the comparison with ESBuild highlights the emphasis on incremental builds and detailed cache granularity with a token-based, almost AI-like approach.