The recent incidents on the Holesky and Sepolia networks have made me think about our current state of testnets and who is most affected by these issues. It also made me reflect on our current approaches for testing hardforks and other coordinated rollouts and where we can improve. In this post, I am hoping to share a little bit of my view on the current state of our testnets and give some suggestions I believe can help us move forward. TLDR Both Holesky and Sepolia Testnets are important for external entities testing their software and infrastructure; they have evolved from being simply a testing playground and are closer to a staging environment. We need clarity on the requirements for Sepolia and Holesky Testnets. Each network has its purpose and different people rely on them for different use cases. Core-devs need a way of testing rollouts and network upgrades that are as close as possible to Mainnet. The fewer gaps we have between Mainnet and these testing environments, the lower the risk of breaking important things. What are Ethereum Testnets? This is a quick primer for those unfamiliar with Ethereum testnets and their purpose. As of today, Ethereum has two (three if you include Ephemery) test networks.