Ethereum developers have filed a proposal that could eventually replace the network's current validator deposit contract and prepare staking for post-quantum cryptography. The reason is simple: Ethereum's existing validator system relies heavily on BLS cryptography , and quantum computers could eventually threaten it. That's not purely theoretical. Google Quantum AI researchers have identified five potential attack paths against Ethereum using quantum computing. The proposal would expand key-size limits so Ethereum can support larger, quantum-resistant cryptographic formats. But there's one particularly important mechanism: The one-way switch The proposal includes an irreversible switch that would permanently stop the deposit contract from accepting new validators using the old BLS credential format. Once activated: BLS deposits stop → newer credential formats take over. That's significant because around 42.4 million ETH , worth roughly $104 billion , ...