Sui SIP-45 Local Fee Markets: Why Fees Get More Predictable

SIP-45 introduces object-level congestion tracking for shared-object writes, shifting Sui’s fee market from a global model to a localized one. Instead of all builders suffering from a single hot contract or NFT mint, fee escalation logic now applies only to the specific shared object experiencing contention. This isolates fee volatility for apps not touching hot objects, making builder costs more predictable and reducing collateral damage from unrelated traffic spikes source.

Builders can now monitor per-object submit success and latency (median, p95), surfacing actionable congestion metrics that were previously invisible. Failure codes are grouped by object cause for actionable debugging, letting teams pinpoint which shared object is the bottleneck rather than guessing at global state. This refactoring of monitoring to surface per-object congestion metrics is a direct response to pre-SIP-45 pain points, where global fee spikes offered no insight into root causes.

Retry logic is also overhauled. Per-object exponential backoff with jitter for retries prevents thundering herd effects on hot objects, while mandatory idempotent retries using request_id ensure safety and correctness even under repeated submission. This is a significant upgrade from generic retry patterns, which previously risked duplicate effects or wasted gas.

Multi-object transaction fee calculation now keys off the highest-congestion object involved. Builders designing transactions that touch multiple shared objects must account for the composability tradeoffs: coupling unrelated objects increases fee risk, as the transaction inherits the worst-case congestion. This forces more deliberate transaction design and encourages state sharding by user or logical partition to mitigate hotspots.

For fee estimation, per-object fee estimation APIs and builder logic updates are now required. Legacy global fee logic and monitoring must migrate to track and respond to per-object fee signals, not just aggregate network state. Migration tips emphasize incremental rollout, dual-tracking old and new metrics, and updating dashboards to highlight object-level congestion.

Apps that only touch owned objects see minimal impact, as pure-owned-object flows bypass the local fee market entirely. This preserves the low-latency, low-fee experience for simple transfers and non-contentious workloads, while shared-object-heavy apps bear the cost of their own contention.

Builders previously faced global fee spikes and a lack of actionable congestion data, especially during network-wide events or popular launches. SIP-45 addresses these pre-existing builder pain points by making congestion—and its costs—local, observable, and actionable source.

The net effect is that fee volatility is now isolated to the actual sources of contention. Monitoring per-object submit success and latency, combined with failure codes grouped by object, gives builders the tools to debug and optimize without guesswork. Retry UX is safer and more efficient, and multi-object transaction design is now a first-class consideration.

For teams migrating legacy code, the main lift is updating fee estimation and monitoring logic to operate at the object level. This means tracking congestion and fee signals per shared object, and refactoring dashboards and alerts to surface the new metrics. The transition is non-trivial but unlocks much finer-grained control and predictability.

Ultimately, SIP-45’s local fee markets make Sui’s builder experience more transparent and less prone to unpredictable spikes. By localizing the impact of congestion, teams can design, monitor, and optimize with far greater precision, while legacy pain points around global fee spikes and opaque congestion are substantially reduced source.