Every transfer knows its invoice. This starter kit ships the three components that make that real on Solana.

Token-2022 transfer hook that rejects any payment not settling a registered invoice. The binding lives inside the token program, so wallets and payers can't strip it. A memo can be dropped; a hook can't.

Indexer and matcher that reconcile bound transfers against your QuickBooks or Xero export. Exact invoice-hash match first, amount+payee heuristic second, confidence score on every row. On 400ms settlement, the books update with the payment, not weeks later.

Escrow PDA state machine: partial, complete, disputed, refunded. 72-hour dispute window, evidence hashes, signed refund claims. No oracle, no court.

What's inside:

- `transfer-hook/`: Anchor program with ExtraAccountMetaList init and the invoice PDA assert that runs at settlement - `escrow/`: Anchor program with deposit_partial, settle, open_dispute, refund - `indexer/`: websocket logSubscribe into the matcher queue, Geyser-swappable - `client/`: PDA derives, hook-aware transfer builder, CSV matcher - `ARCHITECTURE.md`: mermaid diagrams of the flow and the dispute state machine

TypeScript is type-checked clean (`tsc --noEmit`). Rust follows Anchor 0.30 and the Token-2022 transfer-hook interface. Built from our real Matchbook ideathon work (Superteam Ukraine / Colosseum, September 2026). MIT licensed. Audit before mainnet.