Applying JIT Packages to TurboRepo in Kakao Story FE: Skipping Builds and Upgrading to Next.js 13.5

The Kakao Story FE Development Team introduced the Just-in-Time (JIT) Packages strategy from TurboRepo in a monorepo environment managing nine services, including KakaoPage. This approach enables immediate code reflection without a build step by directly referencing package source code, requiring moduleResolution to be set to bundler. During implementation, import paths for libraries such as xstate needed to be modified. An issue where moduleResolution was forcibly reverted to node in Next.js version 12 was resolved by upgrading to Next.js 13.5 or higher. While JIT application improved development efficiency, there are trade-offs to consider, such as increased build times and versioning management.