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Provably-fair proof

This page reproduces the winner computation from public inputs. You can recompute every step in your browser's DevTools — don't trust our math, verify it.

1. Pre-commit (server_seed_hash)

Published when the draw went live (2026-05-19T19:37:55.965Z).

c8410e3dd1ad423de64946f8943fac8eac881dd1c67558fa42eea534ece2401e

2. Reveal (server_seed)

Revealed after draw (2026-05-20T19:38:31.966Z).

3083d10e591f23f58085de3d48984cc34a32b88b4713ec0e8533a0857827f5bd

Hash check: ✓ sha256(server_seed) === published hash

3. Client seed inputs (all sold eggs)

#WalletWinner?
1BGDKeT...iukC🎉
52BGDKeT...iukC
58BGDKeT...iukC

4. Derived client_seed

client_seed = sha256(sorted by entry_number, joined as "N:wallet" with '|')

035afcd6c9eac0eb71aafc5a12285f44898a6ed762742230942e130fd0eb41cf

5. External entropy (Bitcoin block)

Mixed into the HMAC input so the draw depends on a value the operator could not have known when the server seed was committed ( 2026-05-19T19:37:55.965Z). Any Bitcoin block mined after the commit works — we take the tip at draw time.

sourcemempool.spaceheight950,276hash00000000000000000001aed886f2edb5274a5b0615b1a173122b4f2b0c351bdablock time2026-05-20T19:34:50.000Z

Cross-check on mempool.space or blockstream.info.

6. Winner computation

HMAC-SHA256(server_seed, "client_seed:lotto_id:source:height:hash"), first 16 hex chars, mod sold_count (3).

hmac = 88a957eb7e993cd272dcaae5696e2a18d94c70e94b2772c7de2891af7f79906b

Computed index: 0 → winning egg: #1

7. Independent verification

Show JS snippet (paste into DevTools)
const seed = "3083d10e591f23f58085de3d48984cc34a32b88b4713ec0e8533a0857827f5bd";
const hashStr = "c8410e3dd1ad423de64946f8943fac8eac881dd1c67558fa42eea534ece2401e";
const clientSeed = "035afcd6c9eac0eb71aafc5a12285f44898a6ed762742230942e130fd0eb41cf";
const lottoId = "5e9e248a-88ed-4240-826f-add9e009eec3";
const sold = 3;
const entropy = "mempool.space:950276:00000000000000000001aed886f2edb5274a5b0615b1a173122b4f2b0c351bda";

async function run() {
  const enc = new TextEncoder();
  const seedBytes = enc.encode(seed);
  const hashed = await crypto.subtle.digest("SHA-256", seedBytes);
  const recomputed = [...new Uint8Array(hashed)]
    .map((b) => b.toString(16).padStart(2, "0")).join("");
  console.log("hashOk:", recomputed === hashStr);

  const key = await crypto.subtle.importKey(
    "raw", seedBytes, { name: "HMAC", hash: "SHA-256" }, false, ["sign"]
  );
  const message = entropy
    ? clientSeed + ":" + lottoId + ":" + entropy
    : clientSeed + ":" + lottoId;
  const sig = await crypto.subtle.sign("HMAC", key, enc.encode(message));
  const hex = [...new Uint8Array(sig)]
    .map((b) => b.toString(16).padStart(2, "0")).join("");
  const idx = Number(BigInt("0x" + hex.slice(0, 16)) % BigInt(sold));
  console.log("hmac:", hex);
  console.log("winnerIndex:", idx);
}
run();