Tickets / Auction & Raffle

Auction & Raffle

Experimental On-chain Ticket Auction & Raffle

This year, we will be holding a pre-sale Auction & Raffle for 100 tickets to Devcon VI. The entirety of the Auction & Raffle will take place on Arbitrum, an Ethereum Layer 2 rollup.

Therefore, we will only accept ETH as a method of payment. We advise bridging funds to Arbitrum ahead of time if you wish to participate in the Auction & Raffle. The minimum bid required to participate in the auction will be the cost of a General Admission Devcon ticket in ETH. Everybody who participates in the Auction & Raffle will get a POAP NFT to indicate participation.

Everybody who participates in the Auction & Raffle will get a POAP NFT to indicate participation.

We'd like to thank the amazing developer team at TrueFi for donating their time and expertise to help us build this project.

Important Dates

  • Auction & Raffle beginsJuly 5th
  • Ticket Sale WavesJuly 18th


  • 1
    Bidding window opens
    July 5 — 08:00 UTC
  • 2
    Bidding window closes
    July 14 — 07:59 UTC
  • 3
    Claiming window opens
    July 14 — 08:00 UTC
  • 4
    Claiming window closes
    July 16 — 08:00 UTC

Minimum bid: 0.25ETH



  • The smart contracts for the Auction & Raffle can be viewed here.
  • The contracts were audited by Trail of Bits, and the Audit Report can be viewed here


The contract uses a series of random numbers to draw the raffle winners. As there is no secure random number generator on Arbitrum, those numbers will be provided to the contract in a transaction after the bidding window closes. Hashes of 10 future Ethereum mainnet blocks will be used as a source of randomness, with each of them drawing 8 raffle winners, thus 80 in total. To prevent miners tampering with the blocks in order to set the contest to their advantage, we’ll salt the hashes using a secret number S. This means that for the random numbers we’ll use the hashes of block hashes and the number S:

random_number_1 = keccak256(block_hash_1, S)

random_number_2 = keccak256(block_hash_2, S)

For transparency reasons, we commit to use a secret number S which hash equals to: keccak256(S) = [insert hash here]

After the raffle is settled, we will reveal the secret number S so that anyone can verify that the random numbers were not tampered with. The following Ethereum mainnet blocks will be used as a source of randomness: [insert block numbers of future mainnet blocks].

Please read the Auction & Raffle Terms & Conditions prior to participating here.


  • How will the auction work?

    The 20 highest bidders in the Auction will pay their bid in exchange for a ticket to Devcon VI. All funds/proceeds will be donated to public goods.

  • How will the raffle work?

    Any participants who do not make the top 20 bids will be funneled into a Raffle to win 1 of 80 tickets to Devcon VI. Each person who wins the Raffle will receive a ticket in exchange for paying the reserve price of a ticket.

    One Raffle winner will be randomly selected to have their ticket be a Golden Ticket to Devcon VI, which means they will receive that ticket for Free.

  • Will I get my money back if I do not win the Auction or win the Raffle?
    • Yes, you will be able to withdraw your funds if you do not win either the Auction or Raffle (minus a 2% fee).
    • Raffle winners will also be able to withdraw all funds above the Reserve price (minus a 2% fee).
  • What will the POAP NFTs be good for?

    There may be future opportunities to provide rewards or discounts to those who hold a Devcon Auction & Raffle POAP NFT.

  • Why are we doing this?


    At Devcon, we have a goal to dogfood built-on-ethereum tech as much as possible. It's a great opportunity to give the community hands-on experience using ethereum-based tech, it's a good opportunity to get feedback on ethereum-based projects, and it's more aligned with our ethos of decentralization and FOSS software.

    A digital Auction and/or Raffle system that is censorship-resistant and independently-verifiable is a concept that, before Ethereum, wasn't really possible. It's also a mechanism that has many real-world use cases. Plus, building it on a layer 2 (rollup) allows users to experiment with rollups and feel first-hand their power (and decreased fees!).

    Provably fair & Provably efficient

    We like auctions because they figure out who wants an item the most, based on how high they are willing to pay for it. This is known as economic efficiency. But this is not the only way to allocate scarce items — and what about someone who really wants to attend Devcon, but can’t compete in the auction? For these folks, raffles are a simple and fair mechanism to draw winners at random.

    With a hybrid mechanism, we get the best of both worlds. 20 tickets will serve the demand of those who just can't miss Devcon at any price, while 80 tickets are given out in a provably fair fashion, at face value.

    Alternate distribution mechanism

    Traditionally, we sell tickets in waves at several different days and times. This however inevitably ends up favoring some time zones more than others. In general, we think there must be better ways (or at least ways with different tradeoffs) to distribute tickets without asking people to wait and refresh a website at a certain time.