When Robinhood Chain meets Bitcoin

NetNat

Capital

“Bitcoin picks the winners.”

winners every draw. Half the pot to one, the rest shared by ten.

Stake NET · Win NAT · Stake NAT

Open my vault

Deposited

– sNET

Current cap – sNET · vault on RobinScan ↗

Next draw

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committed block –

oracle: – · last attestation at block –

Settled draws

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– winners paid, prizes staked in NATStaking

See every draw →

Last settled draw

Draw –

Block on mempool.space ↗ Settlement on RobinScan ↗

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NAT

settled pot

committed Bitcoin block

Block hash

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Seed = keccak256(hash ‖ vault ‖ draw number)

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Attestations

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Keeper reward

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Tickets in play

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Prizes

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Rank

Winner

Share

NAT staked

Proof

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Committed Bitcoin blocks, settled draws

All draws →

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How to verify it yourself

“Bitcoin picks. Attestors relay. You verify.”

Five readings, no trust required

01 · The committed height

Read the committed height in the vault before the draw. It is fixed from the last attested height, before the block exists.

drawInfo(–) → –

02 · The Bitcoin hash

Take the block hash from mempool.space or your own node and compare it with the oracle. The hash is used as is, as bytes32.

getHash(–) → –

03 · The seed

seed = keccak256(abi.encodePacked(hash, vault, draw number)). Hash, then vault address, then number: the only source of randomness, and nobody can choose it.

drawSeed(–, hash) → –

04 · The tickets

For i from 0 to 10, ticket r = keccak256(abi.encodePacked(seed, i)) mod totalWeight. Eleven numbers, one per prize, over the ticket list frozen at the sweep.

totalWeight –

05 · The winners

drawTicketOwner(draw, r) returns the address holding ticket r. The same address can win several prizes. Compare with DrawSettled, and with winnersOf in v2.

full recipe → Verify