How it works
Ledger accepts billing evidence, translates it into a provider-neutral contract, calculates cost from a declared basis, reconciles the result, and only then publishes immutable Cost Pools.
Accept immutable billing files with checksums, source metadata, and organization ownership.
Convert provider rows into a readable FOCUS-aligned financial core without losing origin.
Materialize exact service and resource costs from a declared authority and cost basis.
Prove source, normalized, calculated, and published totals agree before release.
Expose formulas, versions, evidence links, corrections, and assumptions with every result.
Submit and verify
The uploaded object records its exact byte size, media type, SHA-256 digest, organization, format, and idempotency identity. Finalization verifies the stored bytes before conversion starts.
Convert
A versioned adapter maps the source into Ledger Normalized Charges. Standard FOCUS fields retain their meanings; provider-specific calculation facts remain evidence or namespaced extensions.
Ingest
Schema, enum, timestamp, currency, precision, and evidence relationships are validated. Atomic, dataset-aware ingestion keeps partial data away from calculation.
Calculate and reconcile
The calculator declares whether it adopts provider-computed values or computes Ledger-owned results. SQL aggregation groups exact amounts without mixing currencies or cost bases.
Publish and explain
Publication creates immutable Cost Pools and evidence links, then atomically moves the logical billing period's current pointer. Historical publications remain available.
Two reconciliation boundaries
Ledger proves that conversion preserved the source totals and that calculation preserved the authoritative normalized total before any Cost Pool is published.
Failure is part of the product
Invalid money, schema, timestamps, evidence, or unsupported semantics reject the import with a stable diagnostic.
Database contention, queue interruption, or runtime infrastructure failures remain retryable and do not relabel evidence as invalid.
The mismatch is persisted with basis, currency, expected value, actual value, and difference. Publication remains blocked.