Claude Code Bookkeeper Playbook Developer Peat Bakke has published a detailed playbook for building a personal and small-business bookkeeping system operated by Claude Code, Anthropic's AI coding assistant. The system, which has run his household and consulting company for nearly a year, uses a plain-text double-entry ledger, scripted bank feeds, and a reconciliation loop that proves cent-level accuracy. Bakke emphasizes that Claude proposes transactions but the owner approves them, and that balance assertions must come from the bank, not the ledger, to avoid hidden errors. From Peat Bakke · peat@peat.org mailto:peat@peat.org · Bluesky @peat.org https://bsky.app/profile/peat.org Fair warning: this is a very nerdy work in progress. It describes a system I built for my own household and my own small business, and it reflects my situation, my banks, and my tolerance for plain-text ledgers. It is not accounting, tax, or legal advice. If you run with it, you do so at your own risk, and please keep a real CPA in the loop. That said, I'm happy to chat. Questions, feedback, and "here's what broke" reports are all welcome by email or on Bluesky. A reconstruction guide for building a personal + small-business bookkeeping system that Claude Code operates. Give this whole document to Claude Code in an empty repository and work through it phase by phase see Part 15, Build order . The system this describes has run a real household and a single-owner consulting company for most of a year: plain-text double-entry ledger, scripted bank feeds, a reconciliation loop that proves the ledger matches the bank to the cent, envelope budgeting, a tax-reserve calculator, payroll splitting, an accountable-plan reimbursement routine, and tax-season document prep. Every private figure has been removed. What remains is the design, the procedures, the file formats, the script contracts, and the rules Claude follows. Prerequisites - Python 3.12 and a virtualenv. - Beancount https://beancount.github.io/ v3 beancount , beanquery , fava . - At least one bank feed: a SimpleFIN Bridge https://beta-bridge.simplefin.org/ subscription covers most US banks and brokerages , and/or a bank with a real API Mercury has a CLI and API , and/or CSV exports. - git , pdftotext poppler if you will parse paystubs. - Claude Code with a CLAUDE.md in the repo root. Conventions in this document -