Crypto and FinTech: money as software state
Engineering notes on P2P deals, TON and Jetton: competing orders, idempotent deposits, withdrawal reservations and balance audits. Examples come from the P2P platform case study.
Jetton Withdrawals: Reservations, Confirmation and Ledger
How to reserve Jetton for withdrawal, release it after failure and avoid duplicate deductions.
TON Deposits: Idempotency and Exact Credit
How a verifiable transaction ID, balance update and ledger prevent a retried webhook from double-crediting TON.
P2P Deal: Listing Locks, Frozen Funds and Release
How a Laravel P2P platform closes listing races and moves funds between deal participants.