The Solana Foundation has initiated the SIMD-0215 proposal, which aims to expand Solana's infrastructure to billions of user accounts. This proposal adds a new hash, called the 'Accounts Lattice Hash', which uses homomorphic hashing to maintain a hash of the entire account state, allowing for fast updates while being secure. This enables: (1) each block to contain the hash of all accounts, not just the accounts that have changed in that block, and (2) the removal of the Epoch Accounts Hash.