Payload

Payload Application Development

Payload is a Next.js native CMS with TypeScript-first architecture, providing admin panel, database management, REST/GraphQL APIs, authentication, and file storage.

Quick Reference

Quick Start

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npx create-payload-app@latest my-app
cd my-app
pnpm dev

Minimal Config

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import { buildConfig } from 'payload'
import { mongooseAdapter } from '@payloadcms/db-mongodb'
import { lexicalEditor } from '@payloadcms/richtext-lexical'
import path from 'path'
import { fileURLToPath } from 'url'

const filename = fileURLToPath(import.meta.url)
const dirname = path.dirname(filename)

export default buildConfig({
  admin: {
    user: 'users',
    importMap: {
      baseDir: path.resolve(dirname),
    },
  },
  collections: [Users, Media],
  editor: lexicalEditor(),
  secret: process.env.PAYLOAD_SECRET,
  typescript: {
    outputFile: path.resolve(dirname, 'payload-types.ts'),
  },
  db: mongooseAdapter({
    url: process.env.DATABASE_URL,
  }),
})

Essential Patterns

Defaults & Conventions

Apply these defaults when modeling content unless there's a clear reason not to:

• Enable drafts/versions by default: versions: { drafts: true }. This is the recommended starting point for any content collection. It auto-injects a _status field (draft / published / changed) — don't add your own status field, it's redundant. Only skip versions for collections that have no publish/draft lifecycle (e.g. internal join tables, settings).
• Use slugField() for all slugs instead of hand-rolling { name: 'slug', type: 'text', unique: true }. It auto-generates the slug from the title, adds a regenerate toggle, and handles uniqueness/indexing for you. It defaults to generating from a title field — if the collection has no title, pass the source field: slugField({ useAsSlug: 'name' }).
• position: 'sidebar' is for short, at-a-glance fields — status, category, author, publish date. Avoid it for long fields that need horizontal space to be usable (description, rich text content, long text). Those belong in the main document area.

Basic Collection

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import type { CollectionConfig } from 'payload'
import { slugField } from 'payload'

export const Posts: CollectionConfig = {
  slug: 'posts',
  admin: {
    useAsTitle: 'title',
    // _status (from versions.drafts) shows the draft/published state — no custom status field needed
    defaultColumns: ['title', 'author', '_status', 'createdAt'],
  },
  versions: {
    drafts: true,
  },
  fields: [
    { name: 'title', type: 'text', required: true },
    slugField(), // auto-generates from `title`, unique + indexed, sidebar position
    { name: 'content', type: 'richText' }, // long field — stays in the main area, not the sidebar
    // short, at-a-glance field — good sidebar candidate
    { name: 'author', type: 'relationship', relationTo: 'users', admin: { position: 'sidebar' } },
  ],
  timestamps: true,
}

For more collection patterns (auth, upload, drafts, live preview), see COLLECTIONS.md.

Common Fields

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// Text field
{ name: 'title', type: 'text', required: true }

// Relationship
{ name: 'author', type: 'relationship', relationTo: 'users', required: true }

// Rich text
{ name: 'content', type: 'richText', required: true }

// Slug — use the helper instead of a hand-rolled text field
slugField()

// Select (for genuine taxonomy — NOT publish state; use versions.drafts + _status for that)
{ name: 'category', type: 'select', options: ['news', 'tutorial', 'opinion'] }

// Upload
{ name: 'image', type: 'upload', relationTo: 'media' }

For all field types (array, blocks, point, join, virtual, conditional, etc.), see FIELDS.md.

Hook Example

Hooks live at one of two levels and they are not interchangeable. Collection hooks receive { doc, data, req, operation, ... } and act on the whole document. Field hooks live inside an individual field's hooks object, receive { value, siblingData, ... }, and return the new value for that field. Computed/virtual fields, per-field formatters, and per-field access masking are field hooks; cross-field business logic is a collection hook.

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// Collection-level: business logic across the document
export const Posts: CollectionConfig = {
  slug: 'posts',
  hooks: {
    beforeChange: [
      async ({ data, operation }) => {
        if (operation === 'create') {
          data.slug = slugify(data.title)
        }
        return data
      },
    ],
  },
  fields: [{ name: 'title', type: 'text' }],
}

// Field-level: compute / format a single field's value (virtual fields use this)
export const Users: CollectionConfig = {
  slug: 'users',
  fields: [
    { name: 'firstName', type: 'text' },
    { name: 'lastName', type: 'text' },
    {
      name: 'fullName',
      type: 'text',
      virtual: true,
      hooks: {
        afterRead: [({ siblingData }) => `${siblingData.firstName} ${siblingData.lastName}`],
      },
    },
  ],
}

When asked to "compute a field" or "populate a field's value in a hook", use a field-level hook on that field — never a collection-level afterRead that mutates doc.

For all hook patterns, see HOOKS.md. For access control, see ACCESS-CONTROL.md.

Access Control with Type Safety

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import type { Access } from 'payload'
import type { User } from '@/payload-types'

// Type-safe access control
export const adminOnly: Access = ({ req }) => {
  const user = req.user as User
  return user?.roles?.includes('admin') || false
}

// Row-level access control
export const ownPostsOnly: Access = ({ req }) => {
  const user = req.user as User
  if (!user) return false
  if (user.roles?.includes('admin')) return true

  return {
    author: { equals: user.id },
  }
}

Query Example

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// Local API
const posts = await payload.find({
  collection: 'posts',
  where: {
    status: { equals: 'published' },
    'author.name': { contains: 'john' },
  },
  depth: 2,
  limit: 10,
  sort: '-createdAt',
})

// Query with populated relationships
const post = await payload.findByID({
  collection: 'posts',
  id: '123',
  depth: 2, // Populates relationships (default is 2)
})
// Returns: { author: { id: "user123", name: "John" } }

// Without depth, relationships return IDs only
const post = await payload.findByID({
  collection: 'posts',
  id: '123',
  depth: 0,
})
// Returns: { author: "user123" }

For all query operators and REST/GraphQL examples, see QUERIES.md.

Getting Payload Instance

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// In API routes (Next.js)
import { getPayload } from 'payload'
import config from '@payload-config'

export async function GET() {
  const payload = await getPayload({ config })

  const posts = await payload.find({
    collection: 'posts',
  })

  return Response.json(posts)
}

// In Server Components
import { getPayload } from 'payload'
import config from '@payload-config'

export default async function Page() {
  const payload = await getPayload({ config })
  const { docs } = await payload.find({ collection: 'posts' })

  return <div>{docs.map(post => <h1 key={post.id}>{post.title}</h1>)}</div>
}

Security Pitfalls

1. Local API Access Control (CRITICAL)

By default, Local API operations bypass ALL access control, even when passing a user.

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// ❌ SECURITY BUG: Passes user but ignores their permissions
await payload.find({
  collection: 'posts',
  user: someUser, // Access control is BYPASSED!
})

// ✅ SECURE: Actually enforces the user's permissions
await payload.find({
  collection: 'posts',
  user: someUser,
  overrideAccess: false, // REQUIRED for access control
})

When to use each:

• overrideAccess: true (default) - Server-side operations you trust (cron jobs, system tasks)
• overrideAccess: false - When operating on behalf of a user (API routes, webhooks)

See QUERIES.md#access-control-in-local-api.

2. Transaction Failures in Hooks

Nested operations in hooks without req break transaction atomicity.

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// ❌ DATA CORRUPTION RISK: Separate transaction
hooks: {
  afterChange: [
    async ({ doc, req }) => {
      await req.payload.create({
        collection: 'audit-log',
        data: { docId: doc.id },
        // Missing req - runs in separate transaction!
      })
    },
  ]
}

// ✅ ATOMIC: Same transaction
hooks: {
  afterChange: [
    async ({ doc, req }) => {
      await req.payload.create({
        collection: 'audit-log',
        data: { docId: doc.id },
        req, // Maintains atomicity
      })
    },
  ]
}

See ADAPTERS.md#threading-req-through-operations.

3. Infinite Hook Loops

Hooks triggering operations that trigger the same hooks create infinite loops.

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// ❌ INFINITE LOOP
hooks: {
  afterChange: [
    async ({ doc, req }) => {
      await req.payload.update({
        collection: 'posts',
        id: doc.id,
        data: { views: doc.views + 1 },
        req,
      }) // Triggers afterChange again!
    },
  ]
}

// ✅ SAFE: Use context flag
hooks: {
  afterChange: [
    async ({ doc, req, context }) => {
      if (context.skipHooks) return

      await req.payload.update({
        collection: 'posts',
        id: doc.id,
        data: { views: doc.views + 1 },
        context: { skipHooks: true },
        req,
      })
    },
  ]
}

See HOOKS.md#context.

Project Structure

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src/
├── app/
│   ├── (frontend)/
│   │   └── page.tsx
│   └── (payload)/
│       └── admin/[[...segments]]/page.tsx
├── collections/
│   ├── Posts.ts
│   ├── Media.ts
│   └── Users.ts
├── globals/
│   └── Header.ts
├── components/
│   └── CustomField.tsx
├── hooks/
│   └── slugify.ts
└── payload.config.ts

Building & Type Generation

Payload generates payload-types.ts for you — you rarely need to run generate:types by hand.

• During development: typescript.autoGenerate defaults to true, so the dev server regenerates types automatically whenever your config changes. Don't run generate:types manually while the dev server is running — it's redundant.
• During builds: payload build generates the import map and types before running next build. Prefer it over calling next build directly so neither is ever stale. Pass --no-types to skip type generation.
• Manual generation (payload generate:types) is an escape hatch — only when neither the dev server nor a build is in the loop (e.g. a one-off script, or CI before a step that doesn't run payload build).

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// payload.config.ts
export default buildConfig({
  typescript: {
    outputFile: path.resolve(dirname, 'payload-types.ts'),
    // autoGenerate defaults to true — types regenerate in dev automatically
  },
})

// Usage
import type { Post, User } from '@/payload-types'

Common Gotchas

1. Local API bypasses access control unless you pass overrideAccess: false
2. Missing req in nested operations breaks transaction atomicity
3. Hook loops — operations in hooks can re-trigger the same hooks; use req.context flags
4. Field-level access returns boolean only, no query constraints
5. Relationship depth defaults to 2; set depth: 0 for IDs only
6. Draft status — _status field is auto-injected when drafts are enabled
7. Types regenerate automatically in dev (autoGenerate) and during payload build — avoid running generate:types manually
8. MongoDB transactions require replica set configuration
9. SQLite transactions are disabled by default; enable with transactionOptions: {}
10. Point fields are not supported in SQLite

Best Practices

Content Modeling

• Enable versions: { drafts: true } by default on content collections; rely on the auto-injected _status field rather than adding a custom status field
• Use slugField() for slugs instead of hand-rolling a unique text field
• Reserve position: 'sidebar' for short, at-a-glance fields (status, category, author, date); keep long fields (description, rich text) in the main area

Security

• Default to restrictive access, gradually add permissions
• Use overrideAccess: false when passing user to Local API
• Field-level access only returns boolean (no query constraints)
• Never trust client-provided data
• Use saveToJWT: true for roles to avoid database lookups

Performance

• Index frequently queried fields
• Use select to limit returned fields
• Set maxDepth on relationships to prevent over-fetching
• Prefer query constraints over async operations in access control
• Cache expensive operations in req.context

Data Integrity

• Always pass req to nested operations in hooks
• Use context flags to prevent infinite hook loops
• Enable transactions for MongoDB (requires replica set) and Postgres
• Use beforeValidate for data formatting
• Use beforeChange for business logic

Type Safety

• Let dev (autoGenerate) and payload build generate types; run generate:types manually only when neither is running
• Import types from generated payload-types.ts
• Type your user object: import type { User } from '@/payload-types'
• Use field type guards for runtime type checking
• When extracting any Payload value into a named constant — a collection, field, hook, access function, plugin, etc. — annotate it with the matching Payload type (CollectionConfig, Field, CollectionBeforeChangeHook, Access, Plugin, …) or use satisfies <Type>. Without an annotation, string properties like type: 'text' widen to string and discriminated unions (Field, CollectionConfig) fail to resolve. Inline literals get this for free via contextual typing; extracted constants do not.

Organization

• Keep collections in separate files
• Extract access control to access/ directory
• Extract hooks to hooks/ directory
• Use reusable field factories for common patterns
• Document complex access control with comments

Reference Documentation

• FIELDS.md - All field types, validation, admin options
• FIELD-TYPE-GUARDS.md - Type guards for runtime field type checking and narrowing
• COLLECTIONS.md - Collection configs, auth, upload, drafts, live preview
• HOOKS.md - Collection hooks, field hooks, context patterns
• ACCESS-CONTROL.md - Collection, field, global access control, RBAC, multi-tenant
• ACCESS-CONTROL-ADVANCED.md - Context-aware, time-based, subscription-based access, factory functions, templates
• QUERIES.md - Query operators, Local/REST/GraphQL APIs
• ENDPOINTS.md - Custom API endpoints: authentication, helpers, request/response patterns
• ADAPTERS.md - Database, storage, email adapters, transactions
• ADVANCED.md - Authentication, jobs, endpoints, components, plugins, localization
• PLUGIN-DEVELOPMENT.md - Plugin architecture, monorepo structure, patterns, best practices

Resources

• llms-full.txt: https://payloadcms.com/llms-full.txt
• Docs: https://payloadcms.com/docs
• GitHub: https://github.com/payloadcms/payload
• Examples: https://github.com/payloadcms/payload/tree/main/examples
• Templates: https://github.com/payloadcms/payload/tree/main/templates