Kwik Nkap API

The Kwik Nkap API is the programmable surface of the Kwik Nkap business platform. Today it covers getting paid: collect Mobile Money payments, raise payment links and invoices, upload their artwork, and receive signed webhooks when money moves. More of the platform becomes callable over time; the conventions below hold as it grows.

Authentication — send your secret key as X-API-Key. Keys are prefixed kn_sk_test_ (sandbox) or kn_sk_live_ (live); the prefix alone decides which environment and which database a request reaches.

Idempotency — send an Idempotency-Key header on every POST. If a request with the same key already completed, its original response is replayed and the response carries Idempotent-Replayed: true, so a network retry cannot charge a customer twice.

Errors — every error returns { error: { type, code, message, request_id } }. Branch on code; quote request_id (also in the X-Request-Id header) when contacting support.

Failed payments carry failure_code and failure_message from a stable, provider-agnostic vocabulary, so the same integration keeps working as we add mobile money providers.