Top 10 API Mistakes Developers Make (and How to Fix Them)

Building an API is easy. Building a scalable, secure, and maintainable API is where most developers fail. This article breaks down the top 10 mistakes that cause real-world production issues—and how to avoid them. Poor API Design (Non-RESTful Structure) A common mistake is designing APIs around actions instead of resources. Endpoints like “getUsers” or “createUser” reflect function calls rather than resource-oriented design. The correct approach is to model APIs around resources such as users, orders, or products. This leads to predictable and consistent endpoints. Why it matters: A well-structured API improves developer experience, reduces confusion, and makes the system easier to extend over time. Misusing HTTP Methods Another frequent issue is ignoring HTTP semantics. Developers often use a single method, typically GET, for all operations including updates and deletions. Each HTTP method has a defined purpose: GET for reading data, POST for creating, PUT or PATCH for updating, and D