State Bloat and Stateless Client

State bloat describes the ongoing growth of a blockchain's "state" — the complete, current set of account balances, smart contract code, and contract storage needed to validate new transactions — which tends to grow over time as more accounts and contracts are created, gradually increasing the storage burden on anyone running a full node (see Kaavon's "Full Node" glossary definition). Left unaddressed, state bloat can make running a full node progressively more resource-intensive, potentially pushing toward centralization among fewer, better-resourced node operators able to afford the growing storage requirement.

A stateless client is a proposed architecture addressing this problem by letting a node verify new blocks using only the specific state data relevant to that block, provided alongside the block as a cryptographic proof, rather than needing to store the blockchain's entire state locally at all. This could let nodes operate with dramatically lower storage requirements, directly countering state bloat's centralizing pressure, though stateless client designs introduce their own tradeoffs around proof size, network bandwidth, and overall protocol complexity that remain active areas of research.