twenty/packages/twenty-docs/developers/extend/apps/data/objects.mdx

---
title: Objects
description: Declare new record types — custom tables with their own fields — using defineObject.
icon: "table"
---

Custom **objects** are new record types your app adds to a workspace — Post Card, Invoice, Subscription, anything specific to your domain. Each object declares its schema (fields, relations, default values) and a stable universal identifier that survives across syncs and deploys.

```ts src/objects/post-card.object.ts
import { defineObject, FieldType } from 'twenty-sdk/define';

enum PostCardStatus {
  DRAFT = 'DRAFT',
  SENT = 'SENT',
  DELIVERED = 'DELIVERED',
  RETURNED = 'RETURNED',
}

export default defineObject({
  universalIdentifier: '54b589ca-eeed-4950-a176-358418b85c05',
  nameSingular: 'postCard',
  namePlural: 'postCards',
  labelSingular: 'Post Card',
  labelPlural: 'Post Cards',
  description: 'A post card object',
  icon: 'IconMail',
  fields: [
    {
      universalIdentifier: '58a0a314-d7ea-4865-9850-7fb84e72f30b',
      name: 'content',
      type: FieldType.TEXT,
      label: 'Content',
      description: "Postcard's content",
      icon: 'IconAbc',
    },
    {
      universalIdentifier: 'c6aa31f3-da76-4ac6-889f-475e226009ac',
      name: 'recipientName',
      type: FieldType.FULL_NAME,
      label: 'Recipient name',
      icon: 'IconUser',
    },
    {
      universalIdentifier: '95045777-a0ad-49ec-98f9-22f9fc0c8266',
      name: 'recipientAddress',
      type: FieldType.ADDRESS,
      label: 'Recipient address',
      icon: 'IconHome',
    },
    {
      universalIdentifier: '87b675b8-dd8c-4448-b4ca-20e5a2234a1e',
      name: 'status',
      type: FieldType.SELECT,
      label: 'Status',
      icon: 'IconSend',
      defaultValue: `'${PostCardStatus.DRAFT}'`,
      options: [
        { value: PostCardStatus.DRAFT, label: 'Draft', position: 0, color: 'gray' },
        { value: PostCardStatus.SENT, label: 'Sent', position: 1, color: 'orange' },
        { value: PostCardStatus.DELIVERED, label: 'Delivered', position: 2, color: 'green' },
        { value: PostCardStatus.RETURNED, label: 'Returned', position: 3, color: 'orange' },
      ],
    },
    {
      universalIdentifier: 'e06abe72-5b44-4e7f-93be-afc185a3c433',
      name: 'deliveredAt',
      type: FieldType.DATE_TIME,
      label: 'Delivered at',
      icon: 'IconCheck',
      isNullable: true,
      defaultValue: null,
    },
  ],
});
```

## Key points

- The `universalIdentifier` must be unique and stable across deployments.
- Each field requires a `name`, `type`, `label`, and its own stable `universalIdentifier`.
- The `fields` array is optional — you can define objects without custom fields.
- Inline fields defined here do **not** need an `objectUniversalIdentifier` — it's inherited from the parent object. Use [`defineField()`](/developers/extend/apps/data/extending-objects) to add fields to objects you don't own.
- You can scaffold new objects with `yarn twenty dev:add object`, which guides you through naming, fields, and relationships. See [Architecture → Scaffolding entities](/developers/extend/apps/getting-started/scaffolding).

<Note>
**Base fields are added automatically.** When you define a custom object, Twenty creates standard fields like `id`, `name`, `createdAt`, `updatedAt`, `createdBy`, `updatedBy`, and `deletedAt` for you. You don't need to declare them in your `fields` array — only your custom fields. You can override a default field by declaring one with the same name, but this is rarely a good idea.
</Note>

## Default values

Literal string defaults must be wrapped in single quotes **inside** the string — `defaultValue: "'Draft'"`, not `defaultValue: "Draft"`. That's why the `status` field above uses `` `'${PostCardStatus.DRAFT}'` ``.

Unquoted strings are reserved for computed defaults, evaluated when a record is created:

- `'uuid'` — generates a UUID (for `UUID` fields)
- `'now'` — the current timestamp (for `DATE_TIME` fields)

The same convention applies to string sub-fields of composite defaults (e.g. `{ source: "'MANUAL'" }` on an `ACTOR` field) and to `SELECT`/`MULTI_SELECT` values. A literal string default left unquoted raises a warning when your app is built.

## Nullability

`isNullable` controls whether a field accepts `NULL`. It defaults to `true` — omit it for optional fields. Set `isNullable: false` to make a field required at the database level.

Changes to `isNullable` are applied on every sync, including syncs that update an existing field — so you can flip a field's nullability by editing the manifest and re-syncing.

<Note>
**Making an existing field non-nullable requires a default value.** When you change a field to `isNullable: false`, you must also provide a non-null `defaultValue`. The default backfills any existing `NULL` rows before the `NOT NULL` constraint is applied; without it the sync fails with `Default value cannot be null for non-nullable fields`. Relation fields and `TS_VECTOR` fields are always nullable, so `isNullable` has no effect on them.
</Note>

```ts
{
  universalIdentifier: 'b1a7c0de-1234-4f00-9abc-000000000000',
  name: 'reference',
  type: FieldType.TEXT,
  label: 'Reference',
  isNullable: false,
  defaultValue: "'N/A'",
}
```

## What's next

- **Connect this object to others** — see [Relations](/developers/extend/apps/data/relations) for the bidirectional relation pattern.
- **Add fields to objects from other apps** — see [Extending Objects](/developers/extend/apps/data/extending-objects) for `defineField()`.
- **Display this object in the UI** — see [Views](/developers/extend/apps/layout/views) and [Navigation Menu Items](/developers/extend/apps/layout/navigation-menu-items) to put it in the sidebar.