Colocate API Calls in Next.js App Router for Scalable Codebases

A frontend engineer at MTN Nigeria shares a pattern for organizing API calls in Next.js 15 App Router by placing them inside feature directories rather than a global services folder. The approach keeps code navigable even with 30+ feature modules, using a shared typed Axios instance for authentication. Each feature module owns its own api/index.ts file, preventing the maze-like structure of centralized services.