wanderbooks/plan/STATUS.md

STATUS — 2026-10-10

Where we are

Phase 1 (semantics core) is underway. The repo exists, is private, and the first engine slice is built, tested, and green.

Done:

• Repo swaits/wanderbooks created on git.swaits.com (private).
• ledger-core 0.1.0: Money (exact Decimal + ISO currency), five account types with normal sides, chart of accounts (codes, hierarchy, placeholders), journal entries with full validation, Ledger command surface (create/add-line/post/reverse), append-only posting log.
• Reports: trial balance, P&L, balance sheet (accounting equation holds; current earnings folded into equity pre-close), canonical JSON snapshot() for oracle diffing.
• 14 tests green: validation rejections, posted-entry immutability, reversal semantics, the accounting laws on a fixture company, a 300-entry randomized invariant test, and the first golden file.
• Docs: AGENTS.md (operating manual), requirements, architecture, oracle design, parity catalog (floor: 6 done), glossary. Plan: this file + roadmap.

In progress: nothing — the next arcs are queued below, unstarted.

Next arcs (in order)

The project went AI-first on 2026-10-10 (Stephen's call): the primary interface is MCP, not a cloned GUI. The engine roadmap (period close, cash flow, proptest) continues as needed, but the next phase is the interface:

1. ledger-store (docs/receipt-store.md): SQLite persistence, append-only triggers, TEXT amounts, event log, migrations, rebuild-from-log verify.
2. Blob store: content-addressed receipts/documents, attachment metadata, Drive backfill script.
3. ledger-mcp (docs/mcp-interface.md): stdio transport first; narrow tools with preview-before-post; digest; read-only resources; the agent operating contract in the tool descriptions.
4. Capability parity (docs/capability-parity.md): build every specced row, then the month-long parallel run against the GSheet; cutover per the cutover rule.
5. Then: oracle harness (GnuCash diff), read-only GUI on the event log, workflow parity.

Decisions log

• 2026-10-10: Single currency per ledger for day one (R-5). Multi-currency is designed-for, not built.
• 2026-10-10: Money arithmetic is checked and returns Result; no panicking ops, no float paths anywhere.
• 2026-10-10: Negative zero is normalized away at account_balance — money never prints "-0". (Caught by the golden test on day one; the oracle works.)
• 2026-10-10: License MIT OR Apache-2.0, matching the storytold projects. GnuCash clean-room boundary documented in docs/oracle.md.
• 2026-10-10: AI-first pivot (Stephen). Primary interface is MCP (docs/mcp-interface.md), not a cloned GUI. Receipts/documents become a content-addressed blob store (docs/receipt-store.md). Parity target for the phase is the GSheet+GDrive system (docs/capability-parity.md), with a parallel-run cutover rule. GUI drops to read-only, event-log-driven, phase 4.
• 2026-10-10: Import/export targets QuickBooks formats (CSV, IIF, XLSX) — "could not give a single shit about GnuCash XML." GnuCash stays the behavioral oracle only. Receipt enforcement is server-side policy in the MCP layer (threshold + per-account overrides, typed receipt_required error, checklist in every preview); the engine stays policy-free.
• 2026-10-10: Storage durability (Stephen). SQLite is the query engine, not the source of truth: the source of truth is an append-only, hash-chained JSONL journal (fsync per append; tamper-evident; git-backup-friendly), SQLite is a disposable projection rebuilt from it, blobs stay content-addressed. Single write path: journal → fsync → apply to SQLite.