Ingest a camt.053 ISO 20022 XML bank statement and reconcile entries against internal payment records

Verified steps

1. Receive the camt.053 XML file (version suffix varies by bank — commonly .002, .006, or .008); validate it against the published XSD schema before parsing to catch truncation or encoding errors introduced during SFTP transfer
2. Extract the top-level GrpHdr/MsgId and CreDtTm for file-level deduplication; then iterate each Stmt element, reading Acct/Id/IBAN (or BBAN) to identify which internal account the statement covers
3. For each Ntry (entry) element, capture: Amt and Ccy, CdtDbtInd (CRDT or DBIT), BookgDt/Dt (booking date), ValDt/Dt (value date for interest calculations), BkTxCd/Domn/Cd and SubFmlyCd (ISO bank transaction code classifying the payment type), and Sts (BOOK confirms settled; PDNG means pending)
4. Descend into NtryDtls/TxDtls for remittance information: RmtInf/Ustrd for unstructured references or RmtInf/Strd/CdtrRefInf/Ref for structured creditor references; match these references against your payment order IDs to auto-reconcile
5. Write each matched entry as a reconciliation event linking the external statement entry ID (AcctSvcrRef) to your internal payment record; flag unmatched entries for manual cash-application review
6. Handle multi-entry batches where a single Ntry summarizes a batch credit and NtryDtls contains one TxDtls per underlying transaction — matching must occur at the TxDtls level, not the Ntry level, to reconcile individual invoices