# References and evidence — D30-F01-A03

Accessed: 25 October 2026. All monetary fixtures are synthetic and author-derived. No employer/customer data or external dataset is redistributed.

| ID | Primary source and version | Role and supported claim | Applicability limit |
|---|---|---|---|
| FS01 | Microsoft Azure Architecture Center, [Event Sourcing pattern](https://learn.microsoft.com/en-us/azure/architecture/patterns/event-sourcing), live official documentation accessed2026-10-25 | Ordered event replay, projections, compensating history and snapshot context | Architecture guidance; does not define accounting or prove speed |
| FS02 | PostgreSQL 18, [Transaction Isolation section 13.2](https://www.postgresql.org/docs/18/transaction-iso.html) | Committed snapshot behavior and distinct statement snapshots under Read Committed | Exporter consistency is a trusted adapter obligation |
| FS03 | PostgreSQL 18, [Transactions section 3.4](https://www.postgresql.org/docs/18/tutorial-transactions.html) | All-or-nothing visibility of grouped transaction changes | Portable replay and receipt timestamps do not prove actual COMMIT instant/durability |
| FS04 | PostgreSQL 18, [Sequence Manipulation Functions section 9.17](https://www.postgresql.org/docs/18/functions-sequence.html) | nextval rollback gaps distinguish SQL sequences from this committed counter | This profile intentionally uses the Stage 1 transactional ledger counter |
| FS05 | Frozen D30 Stage 0 and Stage 2 contracts, repository author specification, ratified2026-10-25 | Exact accounting signs, strict fields, units, cutoffs, registry and reason limits | Teaching implementation choices, jurisdiction-neutral fictional bank |

## Source versions and ownership

PostgreSQL links explicitly select major version18. Microsoft documentation is a live page; the access date identifies the checked text, not an immutable page version. The local source ledger is research/SOURCE-LEDGER.md. The frozen complete data contract is mirrored in examples/DATA-CONTRACT.md.

## Claim classification

Architecture/database statements cite FS01–FS04. The complete head/group/query/checkpoint shapes, resource bounds, cutoff equality, retained adjustment reason and typed rejection policy are implementation choices. The100000 funding,2500 wrong transfer,2400 replacement and250 fee are synthetic. Balances100000,97500,97600,97350 are independently calculated arithmetic. No causal business-performance, speed, universal regulatory or forecast claim is made.

## Historical-example decision

**Not useful.** No named historical ledger is needed to test deterministic replay, whole-group visibility or missing evidence. A real-case extension would require redistributable journal data, immutable account conventions, actual consistent export receipts and complete correction lineage; a few headline transactions would not suffice.


Supports: FS01–FS04 support only the specifically attributed architecture/database facts above.

Limitations: Schemas, cutoffs, resource limits, arithmetic and fictional account data are author choices; no source proves authenticity or performance of this portable reader.