Module orchestration 

Epoch-boundary orchestration.

Traces to: SPEC §10.

Role

run_epoch_boundary is the single public entry point an embedder calls once per epoch-boundary to drive every per-epoch piece of slashing state forward in a FIXED, spec-mandated order. Each downstream step depends on the state produced by earlier steps; reordering is a protocol error and pinned by DSL-127’s order tests.

Spec-mandated step order:

1. Compute flag deltas over participation’s previous-epoch flags.
2. Update inactivity scores over the same previous-epoch flags.
3. Compute inactivity-leak penalties for the ending epoch.
4. Finalise expired slashes (correlation penalty + reporter- bond release + exit lock).
5. Rotate ParticipationTracker to current_epoch_ending + 1.
6. Advance SlashingManager epoch.
7. Resize trackers if validator_count changed.
8. Prune old processed evidence + correlation-window entries.

Why this order

• 1 before 2 — update_for_epoch reads the same previous-epoch flags the flag-delta computation reads. Running the update first would rotate the tracker before the delta pass, losing the previous-epoch data permanently.
• 3 before 4 — finalise uses correlation data that must reflect the most recent inactivity update; if penalties were computed after finalise, the cohort would use stale scores.
• 4 before 5 — finalise_expired_slashes reads correlation_window entries keyed by the CURRENT epoch; rotating the participation tracker first would confuse other consumers into believing the new epoch is active while the manager is still mid-finalise.
• 8 last — pruning drops evidence and correlation rows that would otherwise be needed by earlier steps.

Structs

EpochBoundaryReport

Summary produced by run_epoch_boundary. Carries every side-effect the caller needs to route downstream (logging, reward payouts, state snapshots).

ReorgReport

Summary produced by rewind_all_on_reorg. Carries per- subsystem rewind outcomes so the caller (a chain-shell orchestrator) can log or emit metrics without re-deriving the rewind scope from internal tracker state.

Traits

JustificationView

Per-epoch finality view. Returns the epoch of the most recently FINALIZED Casper-FFG checkpoint. DSL-127 consults this to derive in_finality_stall; the orchestrator does not require a full Casper view, only the finalized-epoch height.

Functions

rewind_all_on_reorg

Global reorg orchestrator. Rewinds every slashing-state subsystem in a fixed order.

run_epoch_boundary

Drive one epoch-boundary pass. See module docs for order.