Bullmark.Sdk (.NET)

Not published yet

The .NET package is planned but not on the feed. TypeScript shipped first because it is what most brands’ checkouts are written in.

Meanwhile, the Partner API is four plain HTTP calls with an X-Api-Key header, and nothing about it needs a client library:

var http = new HttpClient { BaseAddress = new Uri("https://api.bullmark.net") };
http.DefaultRequestHeaders.Add("X-Api-Key", apiKey);

var res = await http.PostAsJsonAsync("/partner/vouchers/redeem", new
{
    code,
    externalRef = order.Id.ToString(),   // the SAME value on every retry
});

For verification, .NET already has the pieces: Axowl.Sdk.Integrity.Hashing computes the same hash the server does. Fetch /partner/vouchers/{code}/events and re-derive it — the algorithm reference describes the exact document.