Petri
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Rebuild the dish from nothing

The contract keeps one ordered ledger: every colony that joined, every purchase and sale, every planting, specimen slide and tide, every clock skip and refund, with the PETRI, NEAR and credit each moved. That is all anyone needs: Life is deterministic, so replaying the ledger from an empty dish must land on exactly the board, the history chain, the PETRI balances, the NEAR vault and the credit pool the contract holds. This page does it now, in your browser, with the same Rust code the contract runs, reading everything from one final block.

The replay stops at the generation the contract last stored. The live dish elsewhere on this site runs a few generations ahead of that in your browser, by the same rules, until someone advances the contract.

0of — generations, the last one the contract stored

Run it from a terminal

What was checked

  • History chain
    On chain
    —
    Replay or rule
    waiting for the replay
  • Board hash: every cell and its owner
    On chain
    —
    Replay or rule
    waiting for the replay
  • Living cells
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every planting was legal, sieges marked
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every planting paid the formula's price
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every planting paid its cell fee
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every licensed planting was a slide of at least licence_min_cells (12) cells, its pattern, and paid the holder of the day (or the agar, for a planter that never attached NEAR)
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every purchase followed the agar's curve
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every sale back followed the curve and the allowance, and none was the house's
    On chain
    —
    Replay or rule
    waiting for the replay
  • Specimens: every slide is its colony's own cells as the dish stood
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every slide's holder and the royalties it was paid
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every tide: ran when due, chain and stored bytes; its share of the vault, split, bounty (none to the house) and storage worked out from the ledger
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every claim took exactly what its colony was owed
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every refund is for exactly the payout it names, once
    On chain
    —
    Replay or rule
    waiting for the replay
  • No colony holding kept PETRI (earned before its first NEAR, or bought with credit) sold PETRI for NEAR or paid for a pact
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every colony's kept PETRI, from the ledger
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every pact kept to the rules, and no planting broke a pact binding its colony
    On chain
    —
    Replay or rule
    waiting for the replay
  • PETRI the dish holds for pact offers not yet accepted
    On chain
    —
    Replay or rule
    waiting for the replay
  • PETRI left in the agar
    On chain
    —
    Replay or rule
    waiting for the replay
  • PETRI sold from the agar for NEAR
    On chain
    —
    Replay or rule
    waiting for the replay
  • PETRI burned by planting, by specimen slides and by unregistering
    On chain
    —
    Replay or rule
    waiting for the replay
  • PETRI paid to slide holders in royalties
    On chain
    —
    Replay or rule
    waiting for the replay
  • PETRI returned to the agar by planting
    On chain
    —
    Replay or rule
    waiting for the replay
  • PETRI bought back by the agar
    On chain
    —
    Replay or rule
    waiting for the replay
  • PETRI set aside for keepers
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every colony's lifetime PETRI earnings
    On chain
    —
    Replay or rule
    waiting for the replay
  • NEAR in the tide vault
    On chain
    —
    Replay or rule
    waiting for the replay
  • NEAR paid in by players
    On chain
    —
    Replay or rule
    waiting for the replay
  • NEAR paid out at tides
    On chain
    —
    Replay or rule
    waiting for the replay
  • Every colony's NEAR won at tides
    On chain
    —
    Replay or rule
    waiting for the replay
  • Credit sponsored, from the ledger
    On chain
    —
    Replay or rule
    waiting for the replay
  • Credit spent in the dish, from the ledger
    On chain
    —
    Replay or rule
    waiting for the replay
  • Credit taken back by its sponsors, from the ledger
    On chain
    —
    Replay or rule
    waiting for the replay
  • NEAR won and not yet claimed, from the ledger
    On chain
    —
    Replay or rule
    waiting for the replay
  • Pending NEAR, from the ledger
    On chain
    —
    Replay or rule
    waiting for the replay
  • The contract's NEAR covers everything it owes, as the ledger counts it
    On chain
    —
    Replay or rule
    waiting for the replay
  • Nobody can change the contract: no full-access key
    On chain
    —
    Replay or rule
    waiting for the replay

Checkpoints, as they were met

  1. Tides appear here as the replay reaches them: each one checks the history chain and the NEAR it paid.

How the history chain is built

Every sixteenth generation the contract hashes the board (each living cell and its owner) and folds that hash into a running chain. At every tide that runs, on a 240th generation, the ledger records the chain. Change one cell anywhere in the past and every later link changes.

chain at 16sha256(previous link,generation 16,hash of the board)chain at 32sha256(previous link,generation 32,hash of the board)chain at 48sha256(previous link,generation 48,hash of the board)chain nowsha256(previous link,generation g,hash of the board)

  1. Your browser reads the rules, the state, the colonies, the whole ledger, each colony's earnings and tide winnings, and the contract account (its keys and its NEAR balance) from petri-v6.testnet on NEAR testnet, all at one final block. Nothing else. The switch at the top of the page picks the dish: free play on testnet or real NEAR on mainnet.

  2. It starts petri-core on an empty dish with all 1,000,000 PETRI in the agar, an empty vault and an empty credit pool, then applies each entry at its generation: it checks every planting is legal and paid the formula's price and its fee, every purchase and sale followed the curve and the sale allowance, every tide ran exactly when due and paid the right shares of the vault and the credit pool, as NEAR or as credit to the right colonies, and every specimen slide holds exactly its colony's living cells as the board stood and burned the rule's price. Between entries it steps Life and feeds the living exactly as the contract does.

  3. At every tide and at the end it compares hashes, PETRI, NEAR and credit with the contract, and checks that the contract's NEAR covers everything it owes. A match means the dish you see, and every coin and NEAR in it, is what the rules produced.

Run it without this page

The same replay runs from a terminal with Node 20 or later, straight against NEAR RPC. It prints each check and exits non-zero on any mismatch.

git clone https://github.com/RohanGlitched/petri
cd petri
node scripts/verify.mjs

# the mainnet dish, or any other dish
node scripts/verify.mjs --network mainnet
node scripts/verify.mjs --contract petri-v6.testnet --network testnet

What this does not prove

  • It proves the board and balances follow from the log. It cannot prove the log itself is complete; that is NEAR’s job, since every planting is a transaction anyone can look up.
  • It reads through public RPC providers. A lying provider could feed you a consistent fake; check against a node you trust if the stakes are high.
  • Token transfers between accounts are not replayed here. They do not touch the dish, and their totals are covered by the contract’s conservation tests.