PUT

Upsert sign in with for a merchant and one or more countries

https://api.kustom.co/config/checkout/v1/config/signInWith

Parameters2 fields

X-merchant-idstringrequiredin header
Merchant identifier
countriesarray<string>optionalin query
ISO 3166-1 alpha-2 country codes (omit for merchant-level default)

Request body5 fields

signInMethods[]array<object>optional
The sign-in methods to configure.
2 fields in signInMethods
- methodstringoptional
  The sign-in method to configure.
  - klarna
- enabledbooleanoptional
  Whether this sign-in method is enabled.
changeReasonstringoptional
Human-readable reason for the change, stored in the change history.
updatedBystringoptional
Identifier of the user or system making the change.

200

Response8 fields

merchantIdstringoptional
Merchant identifier.
countrystringoptional
ISO 3166-1 alpha-2 country code, or null for the merchant-level default.
signInMethods[]array<object>optional
The configured sign-in methods.
2 fields in signInMethods
- methodstringoptional
  The sign-in method to configure.
  - klarna
- enabledbooleanoptional
  Whether this sign-in method is enabled.
revisioninteger · int64optional
Monotonically increasing revision of this configuration value.
updatedBystringoptional
Identifier of the user or system that last updated the value.
updatedAtstring · date-timeoptional
Timestamp of the last update.

400

Response8 fields

Schema validation failure

merchantIdstringoptional
Merchant identifier.
countrystringoptional
ISO 3166-1 alpha-2 country code, or null for the merchant-level default.
signInMethods[]array<object>optional
The configured sign-in methods.
2 fields in signInMethods
- methodstringoptional
  The sign-in method to configure.
  - klarna
- enabledbooleanoptional
  Whether this sign-in method is enabled.
revisioninteger · int64optional
Monotonically increasing revision of this configuration value.
updatedBystringoptional
Identifier of the user or system that last updated the value.
updatedAtstring · date-timeoptional
Timestamp of the last update.

PUT https://api.kustom.co/config/checkout/v1/config/signInWith

Request body· application/json

{
  "signInMethods": [
    {
      "method": "klarna",
      "enabled": true
    }
  ],
  "changeReason": "Enable Klarna sign-in for Sweden",
  "updatedBy": "ops@acme.com"
}

10 lines

Response 200· OK

[
  {
    "merchantId": "M123456",
    "country": "SE",
    "signInMethods": [
      {
        "method": "klarna",
        "enabled": true
      }
    ],
    "revision": 3,
    "updatedBy": "kustom-external-api",
    "updatedAt": "2026-06-22T14:30:00Z"
  }
]

15 lines

Response 400· Schema validation failure

[
  {
    "merchantId": "M123456",
    "country": "SE",
    "signInMethods": [
      {
        "method": "klarna",
        "enabled": true
      }
    ],
    "revision": 3,
    "updatedBy": "kustom-external-api",
    "updatedAt": "2026-06-22T14:30:00Z"
  }
]

15 lines

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