consensus

Pure Rust implementation of Bitcoin's bitcoinconsensus verification surface (historically exposed as libbitcoinconsensus).

Status

• Legacy, P2SH, SegWit v0, and Taproot/Tapscript validation are implemented.
• Differential checks against Bitcoin Core are available with the core-diff feature.
• Core vectors are vendored in tests/data/.
• Large script-assets corpus support is available via upstream minimizer artifacts.

API

Main entrypoints in src/lib.rs:

• verify
• verify_with_flags
• verify_with_details
• verify_with_flags_detailed

Feature Flags

• std (default)
• external-secp (implies std)
• core-diff (enables Core runtime differential tests/benchmarks)

Quick Start

cargo test

cargo test --features core-diff

Fixture integrity check:

cargo test --test core_fixture_hashes

Core runtime differential (local Core checkout required):

BITCOIN_CORE_REPO=/path/to/bitcoin \
CORE_CPP_DIFF_BUILD_HELPER=1 \
cargo test --features core-diff --test core_cpp_runtime_diff -- --nocapture

Strict parity mode:

BITCOIN_CORE_REPO=/path/to/bitcoin \
CORE_CPP_DIFF_BUILD_HELPER=1 \
CORE_CPP_DIFF_REQUIRED=1 \
CORE_CPP_DIFF_STRICT=1 \
CORE_CPP_DIFF_ACCEPTED_SKIPS=noncanonical_flags,placeholder_vectors \
cargo test --features core-diff --test core_cpp_runtime_diff -- --nocapture

Script-assets parity profile:

SCRIPT_ASSETS_PARITY_PROFILE=1 \
SCRIPT_ASSETS_REQUIRE_UPSTREAM=1 \
SCRIPT_ASSETS_UPSTREAM_JSON=/path/to/script_assets_test.json \
SCRIPT_ASSETS_UPSTREAM_METADATA_JSON=/path/to/script_assets_test.metadata.json \
cargo test --test script_assets -- --nocapture

Benchmarks

cargo bench --bench verification

cargo bench --bench verification --features core-diff

Project Layout

• src/lib.rs: public API and verification flow
• src/script.rs: script interpreter
• src/tx.rs: transaction parsing and sighash helpers
• tests/: vectors, corpus checks, and differential suites

Documentation

• docs/integration-roadmap.md: parity roadmap and findings
• docs/github-ci.md: CI and GitHub setup details

Notes

• Taproot checksig/sighash paths require prevout context (spent_outputs).
• Under VERIFY_TAPROOT, non-taproot execution paths do not fail early when prevouts are absent.
• Amount semantics follow Core runtime: explicit amount is authoritative for checksig/sighash.