| name | graphql |
| description | GraphQL gives clients exactly the data they need - no more, no less. One endpoint, typed schema, introspection. But the flexibility that makes it powerful also makes it dangerous. Without proper contr |
| category | Document Processing |
| source | antigravity |
| tags | ["typescript","react","node","nextjs","api","ai","design","document","security","rag"] |
| url | https://github.com/sickn33/antigravity-awesome-skills/tree/main/skills/graphql |
GraphQL
GraphQL gives clients exactly the data they need - no more, no less. One
endpoint, typed schema, introspection. But the flexibility that makes it
powerful also makes it dangerous. Without proper controls, clients can
craft queries that bring down your server.
This skill covers schema design, resolvers, DataLoader for N+1 prevention,
federation for microservices, and client integration with Apollo/urql.
Key insight: GraphQL is a contract. The schema is the API documentation.
Design it carefully.
2025 lesson: GraphQL isn't always the answer. For simple CRUD, REST is
simpler. For high-performance public APIs, REST with caching wins. Use
GraphQL when you have complex data relationships and diverse client needs.
Principles
- Schema-first design - the schema is the contract
- Prevent N+1 queries with DataLoader
- Limit query depth and complexity
- Use fragments for reusable selections
- Mutations should be specific, not generic update operations
- Errors are data - use union types for expected failures
- Nullability is meaningful - design it intentionally
Capabilities
- graphql-schema-design
- graphql-resolvers
- graphql-federation
- graphql-subscriptions
- graphql-dataloader
- graphql-codegen
- apollo-server
- apollo-client
- urql
Scope
- database-queries -> postgres-wizard
- authentication -> authentication-oauth
- rest-api-design -> backend
- websocket-infrastructure -> backend
Tooling
Server
- @apollo/server - When: Apollo Server v4 Note: Most popular GraphQL server
- graphql-yoga - When: Lightweight alternative Note: Good for serverless
- mercurius - When: Fastify integration Note: Fast, uses JIT
Client
- @apollo/client - When: Full-featured client Note: Caching, state management
- urql - When: Lightweight alternative Note: Smaller, simpler
- graphql-request - When: Simple requests Note: Minimal, no caching
Tools
- graphql-codegen - When: Type generation Note: Essential for TypeScript
- dataloader - When: N+1 prevention Note: Batches and caches
Patterns
Schema Design
Type-safe schema with proper nullability
When to use: Designing any GraphQL API
SCHEMA DESIGN:
"""
The schema is your API contract. Design nullability
intentionally - non-null fields must always resolve.
"""
type Query {
Non-null - will always return user or throw
user(id: ID!): User!
Nullable - returns null if not found
userByEmail(email: String!): User
Non-null list with non-null items
users(limit: Int = 10, offset: Int = 0): [User!]!
Search with pagination
searchUsers(
query: String!
first: Int
after: String
): UserConnection!
}
type Mutation {
Input types for complex mutations
createUser(input: CreateUserInput!): CreateUserPayload!
updateUser(id: ID!, input: UpdateUserInput!): UpdateUserPayload!
deleteUser(id: ID!): DeleteUserPayload!
}
type Subscription {
userCreated: User!
messageReceived(roomId: ID!): Message!
}
Input types
input CreateUserInput {
email: String!
name: String!
role: Role = USER
}
input UpdateUserInput {
email: String
name: String
role: Role
}
Payload types (for errors as data)
type CreateUserPayload {
user: User
errors: [Error!]!
}
union UpdateUserPayload = UpdateUserSuccess | NotFoundError | ValidationError
type UpdateUserSuccess {
user: User!
}
Enums
enum Role {
USER
ADMIN
MODERATOR
}
Types with relationships
type User {
id: ID!
email: String!
name: String!
role: Role!
posts(limit: Int = 10): [Post!]!
createdAt: DateTime!
}
type Post {
id: ID!
title: String!
content: String!
author: User!
comments: [Comment!]!
published: Boolean!
}
Pagination (Relay-style)
type UserConnection {
edges: [UserEdge!]!
pageInfo: PageInfo!
totalCount: Int!
}
type UserEdge {
node: User!
cursor: String!
}
type PageInfo {
hasNextPage: Boolean!
hasPreviousPage: Boolean!
startCursor: String
endCursor: String
}
DataLoader for N+1 Prevention
Batch and cache database queries
When to use: Resolving relationships
DATALOADER:
"""
Without DataLoader, fetching 10 posts with authors
makes 11 queries (1 for posts + 10 for each author).
DataLoader batches into 2 queries.
"""
import DataLoader from 'dataloader';
// Create loaders per request
function createLoaders(db) {
return {
userLoader: new DataLoader(async (ids) => {
// Single query for all users
const users = await db.user.findMany({
where: { id: { in: ids } }
});
// Return in same order as ids
const userMap = new Map(users.map(u => [u.id, u]));
return ids.map(id => userMap.get(id) || null);
}),
postsByAuthorLoader: new DataLoader(async (authorIds) => {
const posts = await db.post.findMany({
where: { authorId: { in: authorIds } }
});
// Group by author
const postsByAuthor = new Map();
posts.forEach(post => {
const existing = postsByAuthor.get(post.authorId) || [];