--- title: Data Model description: Define objects, fields, roles, and application metadata with the Twenty SDK. icon: "database" --- The `twenty-sdk` package provides `defineEntity` functions to declare your app's data model. You must use `export default defineEntity({...})` for the SDK to detect your entities. These functions validate your configuration at build time and provide IDE autocompletion and type safety. **File organization is up to you.** Entity detection is AST-based — the SDK finds `export default defineEntity(...)` calls regardless of where the file lives. Grouping files by type (e.g., `logic-functions/`, `roles/`) is just a convention, not a requirement. Roles encapsulate permissions on your workspace's objects and actions. ```ts restricted-company-role.ts import { defineRole, PermissionFlag, STANDARD_OBJECT_UNIVERSAL_IDENTIFIERS, } from 'twenty-sdk/define'; export default defineRole({ universalIdentifier: '2c80f640-2083-4803-bb49-003e38279de6', label: 'My new role', description: 'A role that can be used in your workspace', canReadAllObjectRecords: false, canUpdateAllObjectRecords: false, canSoftDeleteAllObjectRecords: false, canDestroyAllObjectRecords: false, canUpdateAllSettings: false, canBeAssignedToAgents: false, canBeAssignedToUsers: false, canBeAssignedToApiKeys: false, objectPermissions: [ { objectUniversalIdentifier: STANDARD_OBJECT_UNIVERSAL_IDENTIFIERS.company.universalIdentifier, canReadObjectRecords: true, canUpdateObjectRecords: true, canSoftDeleteObjectRecords: false, canDestroyObjectRecords: false, }, ], fieldPermissions: [ { objectUniversalIdentifier: STANDARD_OBJECT_UNIVERSAL_IDENTIFIERS.company.universalIdentifier, fieldUniversalIdentifier: STANDARD_OBJECT_UNIVERSAL_IDENTIFIERS.company.fields.name.universalIdentifier, canReadFieldValue: false, canUpdateFieldValue: false, }, ], permissionFlags: [PermissionFlag.APPLICATIONS], }); ``` Every app must have exactly one `defineApplication` call that describes: - **Identity**: identifiers, display name, and description. - **Permissions**: which role its functions and front components use. - **(Optional) Variables**: key–value pairs exposed to your functions as environment variables. - **(Optional) Pre-install / post-install functions**: logic functions that run before or after installation. ```ts src/application-config.ts import { defineApplication } from 'twenty-sdk/define'; import { DEFAULT_ROLE_UNIVERSAL_IDENTIFIER } from 'src/roles/default-role'; export default defineApplication({ universalIdentifier: '39783023-bcac-41e3-b0d2-ff1944d8465d', displayName: 'My Twenty App', description: 'My first Twenty app', icon: 'IconWorld', applicationVariables: { DEFAULT_RECIPIENT_NAME: { universalIdentifier: '19e94e59-d4fe-4251-8981-b96d0a9f74de', description: 'Default recipient name for postcards', value: 'Jane Doe', isSecret: false, }, }, defaultRoleUniversalIdentifier: DEFAULT_ROLE_UNIVERSAL_IDENTIFIER, }); ``` Notes: - `universalIdentifier` fields are deterministic IDs you own. Generate them once and keep them stable across syncs. - `applicationVariables` become environment variables for your functions and front components (e.g., `DEFAULT_RECIPIENT_NAME` is available as `process.env.DEFAULT_RECIPIENT_NAME`). - `defaultRoleUniversalIdentifier` must reference a role defined with `defineRole()` (see above). - Pre-install and post-install functions are detected automatically during the manifest build — you do not need to reference them in `defineApplication()`. #### Marketplace metadata If you plan to [publish your app](/developers/extend/apps/publishing), these optional fields control how it appears in the marketplace: | Field | Description | |-------|-------------| | `author` | Author or company name | | `category` | App category for marketplace filtering | | `logoUrl` | Path to your app logo (e.g., `public/logo.png`) | | `screenshots` | Array of screenshot paths (e.g., `public/screenshot-1.png`) | | `aboutDescription` | Longer markdown description for the "About" tab. If omitted, the marketplace uses the package's `README.md` from npm | | `websiteUrl` | Link to your website | | `termsUrl` | Link to terms of service | | `emailSupport` | Support email address | | `issueReportUrl` | Link to issue tracker | #### Roles and permissions The `defaultRoleUniversalIdentifier` in `application-config.ts` designates the default role used by your app's logic functions and front components. See `defineRole` above for details. - The runtime token injected as `TWENTY_APP_ACCESS_TOKEN` is derived from this role. - The typed client is restricted to the permissions granted to that role. - Follow least-privilege: create a dedicated role with only the permissions your functions need. ##### Default function role When you scaffold a new app, the CLI creates a default role file: ```ts src/roles/default-role.ts import { defineRole, PermissionFlag } from 'twenty-sdk/define'; export const DEFAULT_ROLE_UNIVERSAL_IDENTIFIER = 'b648f87b-1d26-4961-b974-0908fd991061'; export default defineRole({ universalIdentifier: DEFAULT_ROLE_UNIVERSAL_IDENTIFIER, label: 'Default function role', description: 'Default role for function Twenty client', canReadAllObjectRecords: true, canUpdateAllObjectRecords: false, canSoftDeleteAllObjectRecords: false, canDestroyAllObjectRecords: false, canUpdateAllSettings: false, canBeAssignedToAgents: false, canBeAssignedToUsers: false, canBeAssignedToApiKeys: false, objectPermissions: [], fieldPermissions: [], permissionFlags: [], }); ``` This role's `universalIdentifier` is referenced in `application-config.ts` as `defaultRoleUniversalIdentifier`: - **\*.role.ts** defines what the role can do. - **application-config.ts** points to that role so your functions inherit its permissions. Notes: - Start from the scaffolded role, then progressively restrict it following least-privilege. - Replace `objectPermissions` and `fieldPermissions` with the objects and fields your functions actually need. - `permissionFlags` control access to platform-level capabilities. Keep them minimal. - See a working example: [`hello-world/src/roles/function-role.ts`](https://github.com/twentyhq/twenty/blob/main/packages/twenty-apps/hello-world/src/roles/function-role.ts). Custom objects describe both schema and behavior for records in your workspace. Use `defineObject()` to define objects with built-in validation: ```ts postCard.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: - Use `defineObject()` for built-in validation and better IDE support. - 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. - You can scaffold new objects using `yarn twenty add`, which guides you through naming, fields, and relationships. **Base fields are created automatically.** When you define a custom object, Twenty automatically adds standard fields such as `id`, `name`, `createdAt`, `updatedAt`, `createdBy`, `updatedBy` and `deletedAt`. You don't need to define these in your `fields` array — only add your custom fields. You can override default fields by defining a field with the same name in your `fields` array, but this is not recommended. Use `defineField()` to add fields to objects you don't own — such as standard Twenty objects (Person, Company, etc.) or objects from other apps. Unlike inline fields in `defineObject()`, standalone fields require an `objectUniversalIdentifier` to specify which object they extend: ```ts src/fields/company-loyalty-tier.field.ts import { defineField, FieldType } from 'twenty-sdk/define'; export default defineField({ universalIdentifier: 'f2a1b3c4-d5e6-7890-abcd-ef1234567890', objectUniversalIdentifier: '701aecb9-eb1c-4d84-9d94-b954b231b64b', // Company object name: 'loyaltyTier', type: FieldType.SELECT, label: 'Loyalty Tier', icon: 'IconStar', options: [ { value: 'BRONZE', label: 'Bronze', position: 0, color: 'orange' }, { value: 'SILVER', label: 'Silver', position: 1, color: 'gray' }, { value: 'GOLD', label: 'Gold', position: 2, color: 'yellow' }, ], }); ``` Key points: - `objectUniversalIdentifier` identifies the target object. For standard objects, use `STANDARD_OBJECT_UNIVERSAL_IDENTIFIERS` exported from `twenty-sdk`. - When defining fields inline in `defineObject()`, you do **not** need `objectUniversalIdentifier` — it's inherited from the parent object. - `defineField()` is the only way to add fields to objects you didn't create with `defineObject()`. Relations connect objects together. In Twenty, relations are always **bidirectional** — you define both sides, and each side references the other. There are two relation types: | Relation type | Description | Has foreign key? | |---------------|-------------|-----------------| | `MANY_TO_ONE` | Many records of this object point to one record of the target | Yes (`joinColumnName`) | | `ONE_TO_MANY` | One record of this object has many records of the target | No (inverse side) | #### How relations work Every relation requires **two fields** that reference each other: 1. The **MANY_TO_ONE** side — lives on the object that holds the foreign key 2. The **ONE_TO_MANY** side — lives on the object that owns the collection Both fields use `FieldType.RELATION` and cross-reference each other via `relationTargetFieldMetadataUniversalIdentifier`. #### Example: Post Card has many Recipients Suppose a `PostCard` can be sent to many `PostCardRecipient` records. Each recipient belongs to exactly one post card. **Step 1: Define the ONE_TO_MANY side on PostCard** (the "one" side): ```ts src/fields/post-card-recipients-on-post-card.field.ts import { defineField, FieldType, RelationType } from 'twenty-sdk/define'; import { POST_CARD_UNIVERSAL_IDENTIFIER } from '../objects/post-card.object'; import { POST_CARD_RECIPIENT_UNIVERSAL_IDENTIFIER } from '../objects/post-card-recipient.object'; // Export so the other side can reference it export const POST_CARD_RECIPIENTS_FIELD_ID = 'a1111111-1111-1111-1111-111111111111'; // Import from the other side import { POST_CARD_FIELD_ID } from './post-card-on-post-card-recipient.field'; export default defineField({ universalIdentifier: POST_CARD_RECIPIENTS_FIELD_ID, objectUniversalIdentifier: POST_CARD_UNIVERSAL_IDENTIFIER, type: FieldType.RELATION, name: 'postCardRecipients', label: 'Post Card Recipients', icon: 'IconUsers', relationTargetObjectMetadataUniversalIdentifier: POST_CARD_RECIPIENT_UNIVERSAL_IDENTIFIER, relationTargetFieldMetadataUniversalIdentifier: POST_CARD_FIELD_ID, universalSettings: { relationType: RelationType.ONE_TO_MANY, }, }); ``` **Step 2: Define the MANY_TO_ONE side on PostCardRecipient** (the "many" side — holds the foreign key): ```ts src/fields/post-card-on-post-card-recipient.field.ts import { defineField, FieldType, RelationType, OnDeleteAction } from 'twenty-sdk/define'; import { POST_CARD_UNIVERSAL_IDENTIFIER } from '../objects/post-card.object'; import { POST_CARD_RECIPIENT_UNIVERSAL_IDENTIFIER } from '../objects/post-card-recipient.object'; // Export so the other side can reference it export const POST_CARD_FIELD_ID = 'b2222222-2222-2222-2222-222222222222'; // Import from the other side import { POST_CARD_RECIPIENTS_FIELD_ID } from './post-card-recipients-on-post-card.field'; export default defineField({ universalIdentifier: POST_CARD_FIELD_ID, objectUniversalIdentifier: POST_CARD_RECIPIENT_UNIVERSAL_IDENTIFIER, type: FieldType.RELATION, name: 'postCard', label: 'Post Card', icon: 'IconMail', relationTargetObjectMetadataUniversalIdentifier: POST_CARD_UNIVERSAL_IDENTIFIER, relationTargetFieldMetadataUniversalIdentifier: POST_CARD_RECIPIENTS_FIELD_ID, universalSettings: { relationType: RelationType.MANY_TO_ONE, onDelete: OnDeleteAction.CASCADE, joinColumnName: 'postCardId', }, }); ``` **Circular imports:** Both relation fields reference each other's `universalIdentifier`. To avoid circular import issues, export your field IDs as named constants from each file, and import them in the other file. The build system resolves these at compile time. #### Relating to standard objects To create a relation with a built-in Twenty object (Person, Company, etc.), use `STANDARD_OBJECT_UNIVERSAL_IDENTIFIERS`: ```ts src/fields/person-on-self-hosting-user.field.ts import { defineField, FieldType, RelationType, OnDeleteAction, STANDARD_OBJECT_UNIVERSAL_IDENTIFIERS, } from 'twenty-sdk/define'; import { SELF_HOSTING_USER_UNIVERSAL_IDENTIFIER } from '../objects/self-hosting-user.object'; export const PERSON_FIELD_ID = 'c3333333-3333-3333-3333-333333333333'; export const SELF_HOSTING_USER_REVERSE_FIELD_ID = 'd4444444-4444-4444-4444-444444444444'; export default defineField({ universalIdentifier: PERSON_FIELD_ID, objectUniversalIdentifier: SELF_HOSTING_USER_UNIVERSAL_IDENTIFIER, type: FieldType.RELATION, name: 'person', label: 'Person', description: 'Person matching with the self hosting user', isNullable: true, relationTargetObjectMetadataUniversalIdentifier: STANDARD_OBJECT_UNIVERSAL_IDENTIFIERS.person.universalIdentifier, relationTargetFieldMetadataUniversalIdentifier: SELF_HOSTING_USER_REVERSE_FIELD_ID, universalSettings: { relationType: RelationType.MANY_TO_ONE, onDelete: OnDeleteAction.SET_NULL, joinColumnName: 'personId', }, }); ``` #### Relation field properties | Property | Required | Description | |----------|----------|-------------| | `type` | Yes | Must be `FieldType.RELATION` | | `relationTargetObjectMetadataUniversalIdentifier` | Yes | The `universalIdentifier` of the target object | | `relationTargetFieldMetadataUniversalIdentifier` | Yes | The `universalIdentifier` of the matching field on the target object | | `universalSettings.relationType` | Yes | `RelationType.MANY_TO_ONE` or `RelationType.ONE_TO_MANY` | | `universalSettings.onDelete` | MANY_TO_ONE only | What happens when the referenced record is deleted: `CASCADE`, `SET_NULL`, `RESTRICT`, or `NO_ACTION` | | `universalSettings.joinColumnName` | MANY_TO_ONE only | Database column name for the foreign key (e.g., `postCardId`) | #### Inline relation fields in defineObject You can also define relation fields directly inside `defineObject()`. In that case, omit `objectUniversalIdentifier` — it's inherited from the parent object: ```ts export default defineObject({ universalIdentifier: '...', nameSingular: 'postCardRecipient', // ... fields: [ { universalIdentifier: POST_CARD_FIELD_ID, type: FieldType.RELATION, name: 'postCard', label: 'Post Card', relationTargetObjectMetadataUniversalIdentifier: POST_CARD_UNIVERSAL_IDENTIFIER, relationTargetFieldMetadataUniversalIdentifier: POST_CARD_RECIPIENTS_FIELD_ID, universalSettings: { relationType: RelationType.MANY_TO_ONE, onDelete: OnDeleteAction.CASCADE, joinColumnName: 'postCardId', }, }, // ... other fields ], }); ``` ## Scaffolding entities with `yarn twenty add` Instead of creating entity files by hand, you can use the interactive scaffolder: ```bash filename="Terminal" yarn twenty add ``` This prompts you to pick an entity type and walks you through the required fields. It generates a ready-to-use file with a stable `universalIdentifier` and the correct `defineEntity()` call. You can also pass the entity type directly to skip the first prompt: ```bash filename="Terminal" yarn twenty add object yarn twenty add logicFunction yarn twenty add frontComponent ``` ### Available entity types | Entity type | Command | Generated file | |-------------|---------|----------------| | Object | `yarn twenty add object` | `src/objects/.ts` | | Field | `yarn twenty add field` | `src/fields/.ts` | | Logic function | `yarn twenty add logicFunction` | `src/logic-functions/.ts` | | Front component | `yarn twenty add frontComponent` | `src/front-components/.tsx` | | Role | `yarn twenty add role` | `src/roles/.ts` | | Skill | `yarn twenty add skill` | `src/skills/.ts` | | Agent | `yarn twenty add agent` | `src/agents/.ts` | | View | `yarn twenty add view` | `src/views/.ts` | | Navigation menu item | `yarn twenty add navigationMenuItem` | `src/navigation-menu-items/.ts` | | Page layout | `yarn twenty add pageLayout` | `src/page-layouts/.ts` | ### What the scaffolder generates Each entity type has its own template. For example, `yarn twenty add object` asks for: 1. **Name (singular)** — e.g., `invoice` 2. **Name (plural)** — e.g., `invoices` 3. **Label (singular)** — auto-populated from the name (e.g., `Invoice`) 4. **Label (plural)** — auto-populated (e.g., `Invoices`) 5. **Create a view and navigation item?** — if you answer yes, the scaffolder also generates a matching view and sidebar link for the new object. Other entity types have simpler prompts — most only ask for a name. The `field` entity type is more detailed: it asks for the field name, label, type (from a list of all available field types like `TEXT`, `NUMBER`, `SELECT`, `RELATION`, etc.), and the target object's `universalIdentifier`. ### Custom output path Use the `--path` flag to place the generated file in a custom location: ```bash filename="Terminal" yarn twenty add logicFunction --path src/custom-folder ```