bsv-tracker

0.2.3, a transaction evidence state machine on bsv-rs ^0.5.0. The tracker owns re-asking: per transaction it keeps a word, the evidence behind it, the hints received and the next re-ask. Checked headers and proofs establish mining and conflicts; broadcaster words only supply hints. A reorg re-asks affected transactions. Hosts provide headers, proofs, hints and time, so wallet, overlay and application hosts can use the same transition logic without giving this crate a network client or a periodic chain scan.

Install

[dependencies]
bsv-tracker = "=0.2.3"

Enable the wasm feature for a wasm host. Cargo.toml disables the SDK's default features and enables transaction types; it adds no HTTP client or async runtime.

Evidence and host obligations

Headers::check constructs checked proof evidence by binding a merkle path to a transaction and comparing its root with the active header snapshot. Stored proofs must be checked again; deserializing bytes does not create a trusted mined state. Hosts only serve current inclusion evidence from a non-suspect Word::Mined and calculate current depth from their current tip.

An unavailable header or failed check keeps the word and schedules a re-ask. Reorg evidence marks affected inclusion stale. Broadcaster rejection and mempool conflict do not by themselves write Rejected or Conflicted. NodeVerdict is a separate host-supplied authority boundary; a host must not relabel a broadcaster's refusal as a local node verdict. The host also supplies the fact that a proved competitor spends one of the tracked inputs.

The host supplies Headers, ProofFetcher, HintSource and Clock, executes scheduled re-asks and reports decoding/check errors. The tracker performs pure transitions and indexed event handling. It does not fetch proofs, select the active header chain or run a script evaluator on the host's behalf.

Events and records

docs/SPEC.md records the specification relationship and docs/CHAIN-EVENTS.md defines the event envelope. Unknown envelope versions, kinds or shapes are errors, not silent tracker inputs. docs/VERIFICATION.md records scoped witnesses; tests contains chain-event vectors and transition tests. Host integration and live transport behavior require their own evidence.

Build and gate

cargo test --locked
cargo fmt --all -- --check
cargo build --locked --target wasm32-unknown-unknown --features wasm

.github/workflows/ci.yml runs test, fmt, clippy, vectors and wasm32 on every PR and main push. The vector job requires the named chain-event and broadcaster-word witnesses to actually execute. RELEASING.md defines tag-based crates.io trusted publishing; CHANGELOG.md records changes. This is a published library, with host adoption controlled separately.

Licensed under MIT OR Apache-2.0, as declared in Cargo.toml.