Base URLs & Environments

Base URL

All API requests use the same base URL:

https://api.ouipay.com/v1

Environments

Environment	Keys	Providers	Money moves?
Sandbox	`sk_test_`	Simulated: real response shapes	No
Live	`sk_live_`	Real payment providers	Yes

Sandbox returns the same response shapes as live, with simulated provider outcomes. The same code path serves both modes: switch the key to go live.

Sandbox vs live

Use sk_test_ keys for development and testing. Test keys never move real money; live keys always do.

Versioning

The API is versioned in the path: /v1/. Within a version:

Backward-compatible only: new fields, new enum values, new endpoints
Unknown values: treat unknown enum values and new fields gracefully; they are not breaking changes
Breaking changes ship under a new version path (/v2/) with a deprecation window for the old one

Request format

Content-Type: application/json for all requests with a body
IDs: ULIDs, e.g. 01M2S17G4A0N9MDMXYSCCX8SPS
Money: integer minor units plus ISO 4217 currency code: 50000 with "NGN" is ₦500.00
Timestamps: ISO 8601 / RFC 3339 in UTC: 2026-09-18T01:13:59Z

Response format

All responses wrap data in a data envelope:

{
  "data": {
    "id": "01M2S17...",
    "status": "completed"
  }
}

Error responses use an error envelope:

{
  "error": {
    "code": "INSUFFICIENT_FUNDS",
    "message": "The wallet balance is insufficient for this payment.",
    "request_id": "OUI-REQ-01M2S18..."
  }
}