GraphQL vs. REST — When to Switch to the New API Paradigm

GitHub announced GraphQL API v4 and the community is going crazy. Is GraphQL really the successor to REST, or is it just hype? After three months of development with GraphQL, we’re sharing our insights.

The Problem with REST¶

Over-fetching and under-fetching. The /users/123 endpoint returns 30 fields, but the mobile client only needs the name and avatar. Or you need a user with orders — two requests instead of one.

Our Pilot: E-commerce Catalog¶

query {
  product(id: "abc123") {
    name
    price
    category { name }
    reviews(first: 5) {
      rating
      author { name }
    }
  }
}

One request, exactly the data you need. In REST, this would be 3 endpoints.

Advantages¶

• Fewer endpoints — one /graphql endpoint
• Strong typing — schema is a contract
• Introspection — auto-generated docs
• Evolution without versioning — you add fields, old queries still work

Problems¶

N+1 queries. Solution: DataLoader pattern. Caching. GraphQL goes over POST, HTTP cache doesn’t work. Monitoring. One endpoint — you have to parse queries.

When REST, When GraphQL¶

GraphQL: multiple clients with different needs, complex data models, mobile applications. REST: simple CRUD, file uploads, webhooks, server-to-server communication.

GraphQL is a Powerful Tool, Not a Silver Bullet¶

Don’t replace REST everywhere — use GraphQL where its advantages outweigh the adoption costs.