Verifiable raffle

PLA+ Glow in the Dark – limited batch

Entries close on October 3, 2026 8:00 pm. 23 entries so far. The seed will be published here right after the draw.

Published record

Algorithm
fld-draw-v1
Commitment (SHA-256 of the seed, published before entries opened)
16dc4e3b05c37f4302994b9f70380bfb7b31e190fe9490511d5496fe48aa86bc
Seed (revealed after the draw)
not revealed yet

How the draw works

  1. Before entries opened we generated a secret 32-byte seed and published its SHA-256 fingerprint (the commitment). Nobody can change the seed afterwards without the fingerprint changing.
  2. When entries closed, the list of entry numbers was frozen and sorted ascending.
  3. A random stream is produced with HMAC-SHA256: key = the seed bytes, message = "fld-draw-v1:" followed by a counter 0, 1, 2, … Each 32-byte block gives eight unsigned 32-bit big-endian numbers.
  4. Numbers in a range 0…n−1 are taken by rejection sampling (values at or above the largest multiple of n below 2³² are skipped), so there is no bias.
  5. The entry list is shuffled with Fisher–Yates from the last position down to the second: for each position i a random j between 0 and i is drawn and the two entries are swapped.
  6. Winners are taken in the resulting order until the allocation is used up; each entry receives at most the quantity it asked for.