GraphQL vs REST: The Honest Comparison (Not the Marketing Version)

Neither is objectively better — they solve different problems well. GraphQL excels when: clients need different subsets of data on different pages, you're serving multiple different client types (mobile app with bandwidth constraints vs. web app with more flexibility), your data model is genuinely graph-like with complex relationships, or you need introspection and typed schemas. REST is better when: your API is simple and resource-focused, you need HTTP caching (GraphQL typically uses POST, which isn't cached), your team is small or unfamiliar with GraphQL's operational complexity, or you need simple curl-testable endpoints.

GraphQL has real operational complexity costs that get glossed over in tutorials. N+1 query problems are common and require DataLoader or similar batching solutions. HTTP-level caching doesn't work out of the box because most GraphQL implementations use POST requests with query bodies — you need application-level caching or persisted queries. Error handling is more complex — GraphQL returns 200 OK even for errors, with errors in the response body. Schema evolution requires careful coordination. Performance monitoring is harder because all requests hit the same endpoint. And the learning curve is steeper than REST for both developers and tooling teams.

Yes, and many production systems do. A common pattern is REST for simple CRUD operations and public-facing simple endpoints (where REST's cacheability and simplicity shine), while using GraphQL for complex data aggregation endpoints that serve multiple client types. Microservices architectures often have individual services with REST APIs, then a GraphQL gateway that aggregates them. The overhead of both isn't huge if they serve genuinely different purposes. Using both just because you can is different from using both where each serves its strengths.