sidestr-core-0.1.0 has been yanked.

sidestr-core

sidestr user-activated sidechains beside a Bitcoin-family parent, in Rust: the chain document, the parents table, signed stock-header blocks (a BIP 325 challenge, no subsidy), the peg-in claim and peg-out burn rules, the block file, and an in-memory validating chain with a producer's mempool.

A sidestr chain runs beside a Bitcoin-family chain with Bitcoin's transaction rules, blocks that are valid because they are signed rather than mined, no subsidy, and every coin on it a coin locked on the parent. Signers decide the order of blocks; they do not decide the rules.

[dependencies]
sidestr-core = "0.1"

Attribution

This crate is a port of siding, the reference implementation of sidestr by Melvin Carvalho — github.com/sidestr/spec, AGPL-3.0 — ported from commit 2de40bdac4cba01be0864156a553d8287c22e279 (siding/lib/{parents,block,chain,overlay,marker,records,address,checkpoint}.mjs, bin/siding.mjs, and the tests in siding/test/). Two parts come from the engine siding loads, by the same author and under the same licence:

the block, header and spending checks from bitcoin-desktop/schema (codec/blocks.js, codec/headers.js, schema/validate.jsonld);
the block file format and the chain state machine from bitcoin-blake/blaketestnode (lib/blockfile.mjs, lib/node.mjs).

SPEC.md in the sidestr repository is the design; the crate documentation cites its sections, and every ported function names its original.

What changed in the port

Bitcoin's consensus serialisation, hashes, merkle roots, the taproot sighash and BIP-340 Schnorr come from rust-bitcoin and its secp256k1; bech32 from the bech32 crate. Nothing cryptographic is hand-rolled.
Script verification fails closed: taproot key-path spends are verified, every other script type is refused rather than skipped. The reference lets a witness version it cannot verify through.
Claim and burn records commit only when a block is applied, not while it is being judged.
Blocks are a pure function of their inputs and the key: BIP 340 auxiliary randomness is zero for every block, as siding sets it for the genesis.
A document naming the assets, pool or evm rules, a level-2 federation, or a BLAKE2b parent is refused, because this version does not carry them.
No I/O in the rules: the filesystem and the clock are behind the std feature (blockfile, chain).

Status — 0.1.0

Level 1 (one signer), the stock header family (parents btc, tbtc4), end to end: genesis from the document, block production, validation, the mempool policy, the block file. Proven against the reference:

the genesis of a throwaway chain rebuilt from its document and key is byte-identical to the one siding wrote (tests/oracle.rs);
the estate's sealed sidestr:dreamlab genesis replays to its documented hash;
blocks produced here are accepted by siding and blocks siding produces are accepted here (tests/interop.rs, needs the reference checkouts).

Not yet: the BLAKE2b v2 header family (sidestr-header), level 2 (several signers, the co-signing round), the assets and pool rules, a parent view (peg-in scanning, paying burns), tips and transactions over Nostr (sidestr-nostr), a full script interpreter.

Running the checks

cargo test                                   # unit, ported siding suites, fixtures, doctests
cargo run --example siding -- replay --chain fixtures/dreamlab/chain.json --dir <dir with blocks.dat>
cargo run --example siding -- genesis --chain chain.json --dir state --key-file signer.key
# the JS interop test, with the reference checkouts:
SIDESTR_SIDING=<sidestr/spec>/siding SCHEMA=<bitcoin-desktop/schema> BLAKETESTNODE=<bitcoin-blake/blaketestnode> \
  cargo test --test interop
RUSTDOCFLAGS="-D warnings" cargo doc --no-deps
cargo clippy --all-targets -- -D warnings && cargo fmt --check

fixtures/trial is a throwaway chain with its disposable signer key, carried for the byte-for-byte test. fixtures/dreamlab is a sealed genesis without its key. Keys are files, never arguments; nothing here prints one.

Licence