aa00c70b06
Produced implementation-guide-taproot-assets-l402-fastapi.md covering all six research areas: 1. Minting: tapcli CLI, Python gRPC (mintrpc.MintAsset), on-chain cost table, single-tx full supply, grouped asset for future issuance, verification commands. LND v0.20 + tapd v0.7 + litd v0.14 confirmed and sourced. 2. Lightning channels: litd integrated mode requirement, litcli channel funding, BTC+TA UTXO coexistence confirmed, RFQ routing via edge nodes (Voltage, Joltz, LnFi), mainnet live since v0.6 (June 2025). Multi-path send flagged missing in v0.7. 3. L402 gate: Aperture flagged NOT PRODUCTION-READY for TA payments. Custom L402 via pymacaroons with currency caveat, N-request session pass, server-side counter requirement. 4. FastAPI+tapd: gRPC stubs path, LNbits TA extension flagged alpha. Full FastAPI endpoints for session creation, payment check, macaroon issuance. REST curl examples added for all key tapd operations (list assets, create address, check transfers, query balance). 5. Hybrid architecture: SQLite schema, fixed-rate SATS_PER_TIMMY peg, 3-phase migration plan. 6. Failure modes: CRITICAL data loss (tapd backup required beyond LND seed), missing features enumerated, mainnet edge node ecosystem confirmed thin but operational. Code review fixes applied: - Fixed macaroon verifier bug: replaced dual satisfy_exact(currency=X) calls (which would require BOTH caveats to be present) with a single satisfy_general() checking one allowed currency value. - Added MACAROON_ROOT_KEY persistent-secret warning in FastAPI code. - Added proto field caveat header (regenerate stubs per tapd release). - Added References table with dated inline source links for all key claims. - Added REST curl quick reference for all tapd operations in §4.1.