swaitsandClaude Opus 5.5
f4cb01b3f9
money() printed whatever scale a Decimal happened to have, so an empty
sum came back as "0" while every other amount read "207.68". Amounts now
have at least two places ("0.00", "1000.00"), padded and never rounded:
an exact FX-converted amount with more places keeps them. Negative zero
normalizes to "0.00".
Test: money_always_has_cents_and_never_rounds; three stdio assertions
that pinned the old "0" now expect "0.00".
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MtYEaR6M6Ybdhm6X98BWNu
wanderbooks
Canonical double-entry bookkeeping, rebuilt from scratch. The engine is verified against oracles, parity is tracked automatically, and the primary interface is AI-first: you talk to an agent, the agent drives the books through MCP. Self-hosted, no rent.
What it is
ledger-core— the semantics engine. Exact decimal money, five account types, balanced journal entries, immutable posted log with reversing entries, trial balance, P&L, balance sheet, indirect-method cash flow, fixed-asset register with straight-line depreciation.ledger-store— durable storage. The source of truth is an append-only, hash-chained JSONL journal; SQLite is a disposable projection rebuilt from it; receipts live in a content-addressed blob store. Drafts are durable, corrupt projections self-heal.ledger-mcp— the AI-first interface. 27 MCP tools over stdio or Streamable HTTP: draft → preview → post workflow, server-side receipt policy (>$25), anti-splitting detection, asset management, digest for human review, plus read-only resources for dashboards.ledger-import— QuickBooks interop. Import bank/credit-card CSVs and chart-of-accounts CSVs; export IIF journal entries (for QuickBooks Desktop) and XLSX reports.
Verification
This is the storytold way applied to accounting: agents verify against oracles, never ship what they haven't demonstrated.
- 70 workspace tests: invariant tests encoding accounting law, golden-file report snapshots, property tests (proptest), end-to-end MCP stdio tests.
- Mutation testing via cargo-mutants; fuzzing via cargo-fuzz (11.5M+ executions, zero crashes).
- GnuCash is the behavioral oracle (never a code source — clean room, MIT OR Apache-2.0).
Status
Parity is 12 of 12 against the spreadsheet workflow it replaces
(docs/capability-parity.md). The parallel-run plan
(docs/parallel-run.md) is written; the Google Sheet stays the system of
record until a clean month and explicit cutover approval.
See plan/STATUS.md for where things stand and
plan/roadmap.md for where it's going.
Quickstart
cargo test # whole suite
cargo run -p ledger-cli -- init ~/books/acme # scaffold a books dir: mise.toml + AGENT.md
cargo run -p ledger-mcp -- --data-dir /tmp/books # MCP server over stdio
Then cd ~/books/acme: mise trust && mise install, mise run build,
mise run mcp-add, and start claude — the agent onboards from AGENT.md.
Layout
crates/ledger-core/ # engine: money, accounts, journal, ledger, reports
crates/ledger-store/ # journal + SQLite projection + blob store
crates/ledger-mcp/ # MCP server: 27 tools, resources, receipt policy
crates/ledger-import/ # QBO CSV import, IIF/XLSX export
docs/ # requirements, architecture, oracle, parity, glossary
plan/ # STATUS.md, roadmap.md
AGENTS.md # operating manual for agents working here
License
MIT OR Apache-2.0. See LICENSE-MIT and LICENSE-APACHE.