Fund Accounting & Fund Economics

This section covers the heart of OpsDNA: the machinery that turns a fund’s legal terms (an LPA, side letters) and its economic events (capital calls, wires, marks, distributions) into an audit-grade general ledger, per-LP capital accounts (PCAP), and Carta-shaped financial statements. Everything here is deterministic because the numbers face auditors and LPs: every figure on a statement must be re-derivable from pinned inputs and provable, not merely stored.

The one-paragraph mental model

Economic policy lives as typed IR payloads in vehicle_terms_versions (ADR-0019 — “the payload IS the IR”). At close time, evaluators in packages/fund-economics/src/runtime/ decode those payloads and apply them to snapshotted facts, emitting canonical <Domain>Application records wrapped in <Domain>ApplicationTrace bundles (ADR-0001). Persistence narrows the canonical records into <Domain>ApplicationRow projections through adapter pairs (ADR-0002) and writes them alongside dimensioned GL journal entries produced by the ledger kernel (packages/ledger/src/kernel.ts). Per-LP PCAP is a rebuildable projection of that canonical state (ADR-0010), and statements are built from the GL + projections by packages/fund-statements-builder. The Acceptance Lab (apps/acceptance-lab) runs whole synthetic funds through this pipeline and asserts the statements tie out.

Flow: runtime → trace → persistence → statements

Why the separation exists

Three properties drive nearly every boundary in this domain:

1. Determinism. Every evaluator is pure over its inputs; every money operation goes through exact-decimal bigint helpers (no IEEE floats); and every material output carries a canonical-JSON hash (application_hash, payload_hash, input_hash/output_hash on calculation_runs). Two runs over the same bytes produce the same bytes.
2. Re-derivation. Projections (PCAP component balances, fund_terms_index) are never systems of record — they can always be rebuilt from canonical GL lines, subledger entries, or terms payloads, and they carry source hashes so staleness is detectable, never silent.
3. Audit. A statement line traces back through journal_line → source_event → calculation_run → terms-version link set, and the runtime trace bundles explain why each decision was made (branch selection, carry-rate lookup chains, per-tier arithmetic steps).

Pages in this section

Key ADRs

Related sections: Entity Model (which vehicle owns which economics), Persistence (repositories, RLS, migrations), Source Pipeline (how bank events become ledger source events).