Fair dice
In Parqués Online nobody can change the dice mid-match, not even us. Here's how it works:
1. A commitment before the start
Before the first roll, the server picks a secret seed and publishes its fingerprint (a hash). The fingerprint is fixed: if the seed changed, the fingerprint wouldn't match.
2. Your seed counts too
Each player contributes their own seed from their device. The dice come from the server's seed combined with every player's, so nobody knows them in advance.
3. Reveal and verify
When the match ends, the server reveals the seed. Your app checks that it matches the fingerprint and recomputes every roll. If something doesn't add up, it tells you.
No tricks in the math
Each die comes from the bytes of an HMAC-SHA256. Bytes that don't split evenly into six faces are discarded, so every face has exactly the same probability.