> ## Documentation Index > Fetch the complete documentation index at: https://docs.getcargo.ai/llms.txt > Use this file to discover all available pages before exploring further. # Attach custom domain > Attach a custom domain to an app or worker ## OpenAPI ````yaml https://api.getcargo.io/openapi.json post /hosting/custom-domains openapi: 3.1.0 info: title: Cargo API version: 1.0.0 description: Cargo Platform API v1 servers: - url: https://api.getcargo.io/v1 description: Cargo API security: - bearerAuth: [] paths: /hosting/custom-domains: post: tags: - Hosting - Custom Domains summary: Attach custom domain description: Attach a custom domain to an app or worker requestBody: required: true content: application/json: schema: oneOf: - type: object properties: kind: type: string const: app appUuid: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-4[0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12})$ title: App UUID description: Identifier of the app this custom domain attaches to. hostname: title: Hostname description: >- Customer-controlled subdomain to attach (e.g. app.example.com). Must be a valid FQDN with at least three DNS labels, must not include a protocol or path, and must not be under a Cargo-owned domain. Normalised to lowercase. type: string minLength: 4 maxLength: 253 required: - kind - appUuid - hostname additionalProperties: false - type: object properties: kind: type: string const: worker workerUuid: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-4[0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12})$ title: Worker UUID description: Identifier of the worker this custom domain attaches to. hostname: title: Hostname description: >- Customer-controlled subdomain to attach (e.g. app.example.com). Must be a valid FQDN with at least three DNS labels, must not include a protocol or path, and must not be under a Cargo-owned domain. Normalised to lowercase. type: string minLength: 4 maxLength: 253 required: - kind - workerUuid - hostname additionalProperties: false title: Request body description: Request body schema. type: object responses: '200': description: Successful response content: application/json: schema: type: object properties: customDomain: oneOf: - type: object properties: uuid: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ workspaceUuid: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ hostname: type: string status: type: string enum: - pending_verification - verifying - active - failed - deactivated verifiedAt: anyOf: - type: string - type: 'null' verification: type: array items: type: object properties: recordType: type: string enum: - CNAME - TXT name: type: string value: type: string required: - recordType - name - value additionalProperties: false cnameTarget: anyOf: - type: string - type: 'null' chargedUntil: type: string createdAt: type: string updatedAt: type: string kind: type: string const: app appUuid: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ required: - uuid - workspaceUuid - hostname - status - verifiedAt - verification - cnameTarget - chargedUntil - createdAt - updatedAt - kind - appUuid additionalProperties: false - type: object properties: uuid: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ workspaceUuid: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ hostname: type: string status: type: string enum: - pending_verification - verifying - active - failed - deactivated verifiedAt: anyOf: - type: string - type: 'null' verification: type: array items: type: object properties: recordType: type: string enum: - CNAME - TXT name: type: string value: type: string required: - recordType - name - value additionalProperties: false cnameTarget: anyOf: - type: string - type: 'null' chargedUntil: type: string createdAt: type: string updatedAt: type: string kind: type: string const: worker workerUuid: type: string format: uuid pattern: >- ^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$ required: - uuid - workspaceUuid - hostname - status - verifiedAt - verification - cnameTarget - chargedUntil - createdAt - updatedAt - kind - workerUuid additionalProperties: false title: Custom domain description: Newly attached custom domain. type: object required: - customDomain additionalProperties: false '400': description: Bad request '401': description: Unauthorized '404': description: Not found '500': description: Internal server error components: securitySchemes: bearerAuth: type: http scheme: bearer ````