The Ethereum Foundation began winding down the Ropsten Testnet and expects to complete the shutdown by the end of December. Major infrastructure providers and most validators have already ceased supporting Ropsten. Etherscan shut down support for Ropsten and Rinkeby in October.
The Foundation also plans to retire the Rinkeby Testnet, which does not support the Merge, by mid-2023. The Merge switched Ethereum from a Proof-of-Work algorithm to Proof-of-Stake in September 2022. Ethereum developers say the switch slashed most of Ethereum’s power usage, making it more environmentally friendly.
However, it was criticized for potentially making Ethereum more centralized by putting more power into the hands of investors who can afford to stake at least 32 ETH. Ethereum developers provided very little clarity on when staked ETH could be unstaked, which can cause issues like Lido’s staked ether token (stETH) causing concern by trading at a discount earlier this year.
Most former Ethereum miners have switched to alternatives like Ethereum Classic or are hopping between cryptocurrencies in an effort to find other profitable coins to mine. Some estimates show that the owners of as much as 200 terahash in computing power that was previously devoted to Ethereum have settled on alternatives to mine.
The Ethereum Foundation encourages app developers who are still using Ropsten to move to the Goerli or Sepolia Testnets. It also invites discussion of the future of its testnets on Ethereum Magicians. A user called q9f posted a proposal on more predictable lifecycles for Ethereum testnets. The proposal suggests launching a new testnet every two years and sunsetting each active testnet after five years.
The Ethereum testnets are primarily used by developers who would like to “beta test” their Ethereum-based applications before moving them to the mainnet.
They can also be used to test proposed Ethereum upgrades. Ethereum developers used Gorli and Sepolia to test and refine the upgrades introduced in the Merge, which makes them more current than Ropsten and Rinkeby. They also plan to activate the Shangdong testnet, which will be used to test some Ethereum Improvement Proposals (EIPs) for the upcoming Shanghai upgrade.
Ropsten and Rinkeby were popular Ethereum testnets. Now the Ethereum Foundation is sunsetting them to make room for new, more up to date testnets that can support post-Merge development of Ethereum-based applications. The newest one, Shangdong, will provide a sandbox for upcoming Ethereum upgrades.