15. STACC: Resource-Based Execution
15.1 Design
STACC is the repository's resource-accounting area. It includes quota calculation, compute-unit metering, account activation and sponsorship, priority handling, weighted scheduling, mempool admission and block assembly. The design explores replacing a user-facing per-transaction gas market with stake-associated resource quotas.
“Zero gas” does not mean zero cost. Validators still pay for CPU, memory, bandwidth, storage, state synchronization and operational security. CU limits are also execution safety limits: exceeding a configured budget aborts execution.
15.2 Resource and Admission Controls
The implementation contains quota and CU-metering interfaces and a weighted-fair scheduler. Their exact behavior depends on the node integration and configuration. Anti-spam policy, sponsorship policy and quota refresh cadence must be validated in a live multi-node network before being described as a complete economic mechanism.
15.3 State Rent
state/state_rent.rs implements a configurable rent collector with exemption balances, grace periods, expiration tracking and collection bookkeeping. The defaults are not a finalized monetary policy. The current repository does not justify claiming a fixed rent burn percentage, automatic cold-storage restoration protocol, or validator redistribution schedule.
15.4 Validator Rewards
stacc/validator_rewards.rs currently exposes a hookable inflation-based reward function that applies a performance score to a supplied base reward. A complete production reward system combining inflation, rent and slash proceeds is not defined by this module.
15.5 Mainnet Requirements
A production STACC specification must fix the quota formula, resource price units, staking relationship, sponsorship rules, anti-spam limits, rent collection semantics, archival guarantees, reward funding, and governance authority. Until those values are committed and tested, STACC is an implemented research subsystem and design direction rather than a finalized economic guarantee.