INSERT-first transfer with lost-reply retry

INSERT-first transfer with lost-reply retry A sequence diagram generated by Archify. POST id=req-7, A->B 200 INSERT request req-7 (UNIQUE) debit A + credit B + log row commit ok 200 OK + result (LOST) at-least-once delivery: the client cannot tell commit from failure retry SAME id + SAME payload INSERT req-7 -> conflict, read row FOUND: SUCCESS, stored result 200 same result (dedup) Submit Lost reply + retry Client · same-id retries · Sequence participant Client same-id retries Transfer API · id+payload+result · Sequence participant Transfer API id+payload+result Ledger DB · requests + log · Sequence participant Ledger DB requests + log Legend main request return async trace message