Crate bsv_overlay_engine 

BSV Overlay Services Engine — core library.

Provides the Engine orchestrator, storage/topic/lookup traits, GASP sync protocol, and all shared types for the overlay network.

This crate is framework-agnostic — it contains zero HTTP or deployment logic. Deployment targets (Cloudflare Workers, Axum, etc.) wrap this crate with HTTP routing.

Modules

advertiser

Advertiser trait — manages SHIP/SLAP overlay advertisements.

backfill

Bounded admin backfills. Continuations select work; persisted cursors own progress.

beef_limits

The engine’s BEEF doors: a stranger’s BEEF, and bytes read back from storage.

broadcaster

Broadcaster traits — propagate transactions to the BSV network and peer overlay nodes.

builder

EngineBuilder — composable configuration for the Overlay Services Engine.

engine

Overlay Services Engine — the core orchestrator.

fault_memo

Compact fault facts, separate from the partial graphs they never resume.

gasp

GASP — Graph Aware Sync Protocol.

gasp_overlay

OverlayGASPStorage — bridges the Engine’s storage to the GASP protocol.

health_checker

HealthChecker trait — checks if an overlay host is reachable.

lookup_service

LookupService trait — indexes admitted outputs and answers lookup queries.

meter

Poll-scoped counters: concurrent futures cannot charge each other’s runs.

node_batch

A batched node request between peers that both answer it (engine 0.2.1, bsv-overlay-cloudflare #58).

page_batch

The sync’s storage per page (engine 0.2.2, the owner’s word of 2026-10-15 on #58’s finding): a GASP page’s admissions are written in one storage batch at the page’s end, and the reads they need are made for the whole page at once.

proof_window

Serving policy for admitted transactions waiting for their own proof.

route_fault

Route faults (engine 0.2.0, bsv-overlay-cloudflare #57).

ship_lookup

Platform transport for SHIP and SLAP discovery during a GASP tick.

storage

Storage trait for the Overlay Services Engine.

stream_sizing

What a read of a BEEF through the streaming reader will hold, estimated from the frame’s LENGTHS AND COUNTS before anything is allocated (bsv-low #585, the doors lens E585-D12-L3).

subject

The SUBJECT of a submitted BEEF — order-independent (loop-2 fleet hardening, 2026-09-05; bsv-low divergence D5).

sync_load

Per-invocation selection and load accounting for GASP.

topic_manager

TopicManager trait — decides which outputs from a transaction to admit into a topic.

types

Core types for the BSV Overlay Services Engine.