After the Constantinople upgrade to Ethereum caused an accidental consensus bug that caused geth and parity to fork on the Ropsten testnet, the team went on to patch the bug right away. This setback was taken in stride by the open-source development team, and stated that they will hold until the completion of the Ethereum Devcon4 conference held in Prague.
The upgrade of Constantinople will be integrated into Ethereum a proof-of-stake consensus (PoS) to coincide with the current proof-of-work (PoW) one. The implementation will head towards to completion of three years of work behind the Casper PoS algorithm.
Constantinople will also include the support of the EIP1234 that would decrease block reward from 3 ETH to 2 ETH as well as postpone the ‘difficulty bomb’ also known as the “ice age” for Ethereum.
According to one developer for the Ethereum Parity network, Afri Schoedon, one of the factors of the accidental fork was due to a lack of mining power as well as nodes not running the correct version. This does come in contrast to another Ethereum developer, Lane Rettig who posted on Twitter:
“One thing I want to make abundantly clear: the lack of miners on Ropsten had *nothing* to do with the Constantinople issuance reduction. As described above, testnet mining is purely altruistic and most major mining pools do NOT mine on Ropsten anyway.”
Rettig did single out that the error was caused by a bug in the consensus algorithm:
“This is a consensus bug and it caused geth and parity to fork. (So, if you’re keeping count, there were now three Ropsten chains: Ropsten Classic, Ropsten geth, and Ropsten parity.”
“This begs the important question: what happens to Constantinople now? As @5chdn and @jutta_steiner have pointed out, it’s likely going to be delayed since we need to be as conservative as possible about mainnet upgrades. But there was no set date for it, anyway.”
Currently, it is expected that another run at a successful testnet is slated sometime before February of 2019.