Preparing for the Ethereum Proof of Stake Merge Event

This document provides information and guidelines for platforms using Zero Hash to prepare for the Ethereum Proof of Stake (PoS) merge event scheduled for September.


The Ethereum mainnet merge to PoS is expected to occur around September 15, resulting in significant changes to the Ethereum blockchain. Zero Hash is implementing measures to ensure smooth transition and continued operation during and after the merge.

Changes and Actions Required

Production Environment (PROD)

  • Withdrawals: Zero Hash will temporarily suspend Ethereum and ERC20 withdrawals before and after the merge, creating a maintenance notification. Trading operations will continue as usual.

Certification Environment (CERT)

  • Testnet Transition: Zero Hash's CERT environment will transition from Ethereum's Ropsten testnet to the Goerli testnet before the merge, targeting September 8th. Existing ETH or ERC20 deposit addresses on Ropsten will need to be recreated on Goerli after the cutover.
  • Smart Contract Addresses: New smart contract addresses will be used in CERT on the Goerli testnet. Platforms should update mappings or allowlisting to the new addresses.

Timeline of Changes

  • Sept 8, 2022: Cutover CERT environment ETH testnet from Ropsten to Goerli. ETH Deposit addresses and allowlists in-use in CERT will need to be recreated on CERT again and updated to the new addresses.
  • Sept 14, 2022: ETH mainnet targeting the merge event. A maintenance window will be created that will pause ETH/ERC20/ETH L2 blockchain activity for approximately 10 minutes.

CERT Smart Contract Addresses

Below are the ERC20 tokens previously supported on Ropsten testnet in CERT, along with their new corresponding Goerli smart contract addresses:

AssetSymbolSmart Contract Address
Basic Attention TokenBAT.ETH0x70cBa46d2e933030E2f274AE58c951C800548AeF
GMO USDZUSD.ETH0x01F5dB4F5bA927Fe73711C745473e6717C039ae3
GMO YenGYEN.ETH0x208d48E7Eb3F316214c28894b3a6aEa9E87C59A5
The GraphGRT.ETH0x1441f298d1f15084A0e5c714c966033E39597dE7
The SandboxSAND.ETH0xbED9a4c4D99f5Ffe90e70996017c78a3bcDd8825
USD CoinUSDC.ETH0x07865c6e87b9f70255377e024ace6630c1eaa37f
Wrapped BTCWBTC.ETH0xC04B0d3107736C32e19F1c62b2aF67BE61d63a05
Wrapped ETHWETH.ETH0xb4fbf271143f4fbf7b91a5ded31805e42b2208d6

Additional Resources

Please contact your client team for any additional questions or assistance regarding the Ethereum Proof of Stake merge event.