Stellar protocol developers discuss Jump Cannon smart contracts implementation, focusing on contract event logging (CAP 51) and multi-dimensional fee models for compute, storage IO, and metadata (CAP 55), with debate over state expiration mechanisms.
In this Stellar open protocol discussion, developers dive deep into two core advancement proposals for Jump Cannon, the smart contracts platform coming to Stellar. CAP 51 introduces contract logging capabilities, allowing contracts to emit data stored in transaction metadata and served by Horizon, with discussion around bloom filters and event filtering strategies. CAP 55 proposes a multi-dimensional fee structure separating compute gas, ledger IO reads/writes, and metadata production into distinct markets, arguing this prevents price inflation compared to aggregate models. A major contentious topic is state expiration, where ledger entries must be renewed periodically or face deletion to prevent infinite ledger growth and ensure fair pricing. Developers debate the implications for users holding assets, with concerns about balances disappearing if not renewed, though proponents argue this is necessary to prevent the ledger from becoming prohibitively expensive.