Struct EngineConfig 

pub struct EngineConfig {

    pub partition_config: PartitionConfig,
    pub lanes: Vec<LaneId>,
    pub lease_expiry_interval: Duration,
    pub delayed_promoter_interval: Duration,
    pub index_reconciler_interval: Duration,
    pub attempt_timeout_interval: Duration,
    pub suspension_timeout_interval: Duration,
    pub pending_wp_expiry_interval: Duration,
    pub retention_trimmer_interval: Duration,
    pub budget_reset_interval: Duration,
    pub budget_reconciler_interval: Duration,
    pub quota_reconciler_interval: Duration,
    pub unblock_interval: Duration,
    pub dependency_reconciler_interval: Duration,
    pub completion_listener: Option<CompletionListenerConfig>,
    pub flow_projector_interval: Duration,
    pub execution_deadline_interval: Duration,
}

Engine configuration.

Fields

partition_config: PartitionConfig

lanes: Vec<LaneId>

Lanes to scan for delayed/index operations. Phase 1: ["default"].

lease_expiry_interval: Duration

Lease expiry scan interval. Default: 1.5s.

delayed_promoter_interval: Duration

Delayed promoter scan interval. Default: 750ms.

index_reconciler_interval: Duration

Index reconciler scan interval. Default: 45s.

attempt_timeout_interval: Duration

Attempt timeout scan interval. Default: 2s.

suspension_timeout_interval: Duration

Suspension timeout scan interval. Default: 2s.

pending_wp_expiry_interval: Duration

Pending waitpoint expiry scan interval. Default: 5s.

retention_trimmer_interval: Duration

Retention trimmer scan interval. Default: 60s.

budget_reset_interval: Duration

Budget reset scan interval. Default: 15s.

budget_reconciler_interval: Duration

Budget reconciler scan interval. Default: 30s.

quota_reconciler_interval: Duration

Quota reconciler scan interval. Default: 30s.

unblock_interval: Duration

Unblock scanner interval. Default: 5s.

dependency_reconciler_interval: Duration

Dependency reconciler interval. Default: 15s.

Post-Batch-C this scanner is a safety net, not the primary promotion path. The completion_listener SUBSCRIBEs to ff:dag:completions and dispatches dependency resolution synchronously with each completion — under normal operation, DAG latency is ~RTT × levels, not interval × levels.

The reconciler still runs as a catch-all for:

• messages missed during listener restart or reconnect;
• pre-Batch-C executions without core.flow_id stamped;
• operator-driven edge mutation that doesn’t pass through the terminal-transition publish path.

15s idle-scan cost is minimal. If the listener is disabled (completion_listener = None), drop this to 1s to preserve pre-Batch-C DAG latency behavior.

completion_listener: Option<CompletionListenerConfig>

Optional push-based DAG promotion listener (Batch C item 6). When Some, the engine spawns a completion_listener task that SUBSCRIBEs to ff:dag:completions on a dedicated RESP3 client and dispatches dependency resolution per completion.

None disables the listener entirely — the reconciler alone promotes. Useful for lightweight single-node deployments or test harnesses that don’t care about DAG latency.

flow_projector_interval: Duration

Flow summary projector interval. Default: 15s.

Separate observability projection path — maintains the flow summary view, NOT on the DAG-completion latency path. Kept at 15s in this config; a change to that cadence is unrelated to dependency resolution.

execution_deadline_interval: Duration

Execution deadline scanner interval. Default: 5s.

Trait Implementations

impl Default for EngineConfig

fn default() -> Self

Returns the “default value” for a type.