$ZKC as Proving Collateral

Using $ZKC as proving collateral on the Boundless market.

• $ZKC is deployed on Ethereum Mainnet and Base Mainnet.
• $ZKC is also bridged to Taiko Alethia.
• To use $ZKC in the Boundless market as Proving Collateral on an L2, $ZKC must be bridged from Ethereum mainnet to that L2.
• Provers also need a small amount of native ETH on the destination L2 to pay for depositCollateral and ongoing market interactions.

Before accepting a proof request, provers must lock $ZKC as collateral in the market, typically at least ~10x the request’s maximum fee. If the proof is not fulfilled on time, the prover is slashed; 50% of the collateral is burned permanently, and the remaining 50% is reassigned onchain as a bounty for another prover to complete the work. This system provides a stronger economic guarantee of proof delivery. At the same time, as the request volume grows, the total amount of $ZKC locked increases by a multiple of ~10x, reducing the total circulating supply.

Bridging $ZKC

$ZKC is deployed at:

• Ethereum Mainnet: 0x000006c2A22ff4A44ff1f5d0F2ed65F781F55555
• (Bridged) Base: 0xAA61bB7777bD01B684347961918f1E07fBbCe7CF
• (Bridged) Taiko Alethia: 0xC284A781072442cC1882a8Db4573990B7B49DaC4

Bridging using Base’s Native Bridges

To bridge $ZKC from Ethereum mainnet to Base mainnet, see the Base documentation for bridging assets to Base.

Manual Bridging using cast

To start, make sure to have cast installed. This will require installing Foundry. Next, export the PRIVATE_KEY for the address holding the $ZKC tokens:

export PRIVATE_KEY=0x1234...5678

Set the AMOUNT and ETH_MAINNET_RPC_URL environment variables:

export AMOUNT=10000000000000000000 # 10 ZKC
ETH_MAINNET_RPC_URL="https://"

with the amount to be bridged, and a valid RPC URL for Ethereum mainnet respectively.

Next, approve the Base bridge to spend $AMOUNT tokens:

cast send 0x000006c2A22ff4A44ff1f5d0F2ed65F781F55555 \
  "approve(address,uint256)" \
  0x3154Cf16ccdb4C6d922629664174b904d80F2C35 \
  $AMOUNT \
  --private-key $PRIVATE_KEY \
  --rpc-url $ETH_MAINNET_RPC_URL

Finally, bridge $AMOUNT tokens:

cast send 0x3154Cf16ccdb4C6d922629664174b904d80F2C35 \
  "bridgeERC20(address,address,uint256,uint32,bytes)" \
  0x000006c2A22ff4A44ff1f5d0F2ed65F781F55555 \
  0xAA61bB7777bD01B684347961918f1E07fBbCe7CF \
  $AMOUNT \
  300000 \
  0x \
  --private-key $PRIVATE_KEY \
  --rpc-url $ETH_MAINNET_RPC_URL

Bridging using Taiko’s Native Bridge

Both $ZKC and native ETH are bridged through the same flow. To bridge from Ethereum mainnet to Taiko Alethia, see bridge.taiko.xyz and Taiko’s contract documentation. The Taiko relayer mints the bridged tokens on L2 a few minutes after L1 confirmation.

Manual Bridging to Taiko using cast

To start, make sure to have cast installed. This will require installing Foundry. Next, export the PRIVATE_KEY for the address holding the $ZKC tokens:

export PRIVATE_KEY=0x1234...5678

Set the AMOUNT, RECIPIENT, FEE, and ETH_MAINNET_RPC_URL environment variables:

export AMOUNT=10000000000000000000 # 10 ZKC
export RECIPIENT=0xYour...Address  # L2 recipient and refund address
export FEE=100000000000000         # 0.0001 ETH processing fee
ETH_MAINNET_RPC_URL="https://"

with the amount to be bridged, the L2 recipient address, the relayer’s native ETH processing fee, and a valid RPC URL for Ethereum mainnet respectively.

Next, approve the Taiko ERC20Vault to spend $AMOUNT tokens:

cast send 0x000006c2A22ff4A44ff1f5d0F2ed65F781F55555 \
  "approve(address,uint256)" \
  0x996282cA11E5DEb6B5D122CC3B9A1FcAAD4415Ab \
  $AMOUNT \
  --private-key $PRIVATE_KEY \
  --rpc-url $ETH_MAINNET_RPC_URL

Finally, bridge $AMOUNT tokens via ERC20Vault.sendToken. The L2 gasLimit must be at least 1,000,000:

cast send 0x996282cA11E5DEb6B5D122CC3B9A1FcAAD4415Ab \
  "sendToken((uint64,address,address,uint64,address,uint32,uint256))" \
  "(167000,$RECIPIENT,$RECIPIENT,$FEE,0x000006c2A22ff4A44ff1f5d0F2ed65F781F55555,1000000,$AMOUNT)" \
  --value $FEE \
  --private-key $PRIVATE_KEY \
  --rpc-url $ETH_MAINNET_RPC_URL