GraphQL vs REST: When to Use What

Having built both GraphQL and REST APIs in production, I’ve learned that the choice isn’t about which is “better” – it’s about which fits your use case. Let me share my experience.

Understanding the Fundamentals

REST: Resource-Based

REST organizes APIs around resources with standard HTTP methods:

GET    /api/users          # List users
GET    /api/users/123      # Get user
POST   /api/users          # Create user
PUT    /api/users/123      # Update user
DELETE /api/users/123      # Delete user

GraphQL: Query-Based

GraphQL uses a single endpoint with typed queries:

query {
  user(id: "123") {
    name
    email
    posts {
      title
      createdAt
    }
  }
}

When to Choose REST

1. Simple CRUD Operations

For straightforward create, read, update, delete operations, REST’s simplicity shines:

// Clean and predictable
func (h *Handler) GetUser(w http.ResponseWriter, r *http.Request) {
    id := chi.URLParam(r, "id")
    user, err := h.userService.GetByID(r.Context(), id)
    if err != nil {
        respondError(w, err)
        return
    }
    respondJSON(w, user)
}

2. Caching is Critical

REST’s URL-based resources work perfectly with HTTP caching:

w.Header().Set("Cache-Control", "public, max-age=3600")
w.Header().Set("ETag", calculateETag(resource))

3. Third-Party Consumers

When building public APIs for external developers, REST’s familiarity and documentation tools (OpenAPI/Swagger) make integration easier.

When to Choose GraphQL

1. Complex, Nested Data

When clients need related data in a single request:

query GetOrderDetails {
  order(id: "456") {
    id
    status
    customer {
      name
      email
    }
    items {
      product {
        name
        price
      }
      quantity
    }
    shipping {
      address
      estimatedDelivery
    }
  }
}

With REST, this would require multiple endpoints or over-fetching.

2. Mobile Applications

Mobile apps benefit from:

• Reduced bandwidth - Request only needed fields
• Fewer round trips - Get all data in one request
• Flexible queries - Different screens, different data needs

3. Rapid Frontend Iteration

When the frontend team needs to move fast without backend changes:

# Week 1: Just need basic info
query { user { name email } }

# Week 2: Now need profile too
query { user { name email profile { bio avatar } } }

# No backend changes required!

Real-World Comparison

Here’s a practical example from my experience:

The REST Approach

# Get user profile page data
GET /api/users/123                    # 200ms
GET /api/users/123/posts?limit=5      # 150ms
GET /api/users/123/followers/count    # 100ms
# Total: 3 requests, ~450ms

The GraphQL Approach

query UserProfile {
  user(id: "123") {
    name
    bio
    avatar
    posts(limit: 5) {
      title
      excerpt
    }
    followersCount
  }
}
# Total: 1 request, ~200ms

Hybrid Approach

In many systems, you don’t have to choose one or the other:

/api/v1/*        # REST for simple CRUD
/graphql         # GraphQL for complex queries

This is the approach we used at SayaKaya:

func main() {
    router := chi.NewRouter()

    // REST endpoints
    router.Route("/api/v1", func(r chi.Router) {
        r.Mount("/users", userRoutes())
        r.Mount("/auth", authRoutes())
    })

    // GraphQL endpoint
    router.Handle("/graphql", graphqlHandler())

    http.ListenAndServe(":8080", router)
}

Performance Considerations

REST Performance Tips

// Use field selection
GET /api/users?fields=id,name,email

// Implement pagination
GET /api/users?page=1&limit=20

// Add caching headers
Cache-Control: public, max-age=300

GraphQL Performance Tips

// Implement DataLoader to batch requests
loader := dataloader.NewBatchedLoader(batchFn)

// Add query complexity limits
complexity := graphql.NewComplexityLimit(100)

// Use persisted queries
query := persistedQueries[queryHash]

My Recommendation

Use Case	Recommendation
Public API	REST
Mobile app backend	GraphQL
Simple CRUD	REST
Complex data requirements	GraphQL
Heavy caching needs	REST
Rapid iteration	GraphQL
Microservices internal	gRPC

Conclusion

Both GraphQL and REST are powerful tools. The key is understanding your requirements:

• Choose REST for simplicity, caching, and public APIs
• Choose GraphQL for flexibility, complex queries, and mobile apps
• Consider both for different parts of your system

Don’t let hype drive your decision. Evaluate based on your specific needs, team expertise, and project constraints.

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What’s your experience with GraphQL vs REST? Share your thoughts!