Licensing your customers can’t spoof.

// POST /api/v1/auth answered, signed with your app key
{
  "ok": true,
  "sd": "v=1|ts=1760412600|nonce=a1b2|hwid=9f3c…|ok=1|
        username=|name=Pro|expires=1790000000|latest_version=2.4.1",
  "sig": "MEUCIQD9nQx2r8…Jb7bQ=="
}

sentry_verify(pubkey, sd, sig)   // → true

using Sentry;

var client = new SentryClient(
    baseUrl, appKey, publicKeyHex,
    useProtocolV2: true);

var r = await client.AuthAsync("KEY-XXXX-YYYY");

if (r.Ok) {
  // verified fields, safe to read
  Console.WriteLine(r.Name);      // license label
  Console.WriteLine(r.Expires);   // or null = lifetime
}

#include "sentry_auth.h"

sentry_config cfg = {0};
cfg.base_url = base_url; cfg.app_key = app_key; cfg.pubkey_hex = pub_hex;
cfg.use_proto3 = 1;

sentry_client *c = sentry_client_new(&cfg, NULL);
sentry_auth_result r;
if (sentry_auth(c, "KEY-XXXX-YYYY", &r) == SENTRY_OK) {
  /* r.name, r.discord_username, r.text_hash: verified, safe to trust */
}