Ethereum Researchers Pursue Verkle Trees, But Stateless Clients Face Significant Challenges

Ethereum clients currently rely on a Merkle Patricia Trie to store state, which includes individual account information stored as leaves on the trie. This requires hashing pairs of leaves repeatedly until only a single root hash remains. However, this process is too resource-intensive for high-performance hardware, and current clients must store the state for both the head block and 128 historical blocks.

Researchers have proposed using Verkle trees to reduce witness size. These trees shorten the distance between leaves and the root, eliminating the need for sibling nodes and reducing data burden on smaller hardware. A Verkle tree witness for 1000 leaves is approximately 150kB, a 23x reduction in size compared to Merkle trees.

However, critics argue that this focus on witness production comes before client utility. Without state, clients cannot participate in transaction gossip or validate transactions, limiting their functionality and making it difficult for new teams to build greenfield projects. Developers must still work on binary trie conversion and code merklization before the benefits of Verkle trees can be fully realized.

Another proposal, Beam Chain, aims to overhaul the consensus layer with 4-second slot times and 3-slot finality. It also suggests lowering validator stakes from 32 ETH to 1 ETH. This plan addresses design mistakes in the Beacon Chain and has a two-year testing phase starting in 2027.