Project Detected: Node.js Express API using CommonJS modules and npm --- Migration Scope: - Added TypeScript support and migrated configuration, middleware, and one user service - Used an incremental migration with JavaScript compatibility enabled --- Changes Applied: - Added TypeScript compiler configuration - Added typecheck and build scripts - Converted config.js, requestLogger.js, and userService.js to TypeScript - Updated affected imports and exports --- Type Safety Improvements: - Added typed environment configuration - Added Express request and response types - Added User and UserServiceResult interfaces - Replaced unvalidated external values with unknown and type guards --- Files Modified: - tsconfig.json - package.json - src/config.ts - src/middleware/requestLogger.ts - src/services/userService.ts - src/types/user.ts --- Commands Executed: - npm install --save-dev typescript @types/node @types/express - npx tsc --noEmit - npm test --- Validation Result: Type checking and the existing test suite passed for the migrated scope. Remaining JavaScript files continue to work through allowJs. --- Remaining Work: - Routes, controllers, remaining services, and JavaScript tests have not yet been migrated --- How to Continue: Migrate one route and its controller together, then rerun npx tsc --noEmit and npm test before selecting the next feature.