QuickBooks Online

Build me a local invoice and expense ledger for a tiny business as a limited substitute for QuickBooks Online. Requirements:

- Use Node, Express, and better-sqlite3 on localhost. Store clients, invoices, line items, payment records, expenses, and import batches in one SQLite file.
- Create invoices with an explicit invoice number, issue date, due date, currency, line items, and user-entered tax amount; render a printable PDF without calculating tax rules.
- Import bank CSV files through a saved column mapping. Show a preview and deduplicate against the same source account, date, amount, and bank transaction identifier when present.
- Record partial payments and show remaining invoice balances. Let me assign expense categories and correct imports without altering the original uploaded file.
- Export invoices, payments, and expenses as separate CSV files for an accountant; show a simple cash-in versus cash-out view labeled as an informal summary.
- Back up the SQLite database with its supported backup API. No accounts, telemetry, payroll, bank feeds, tax filing, or claims of accounting compliance.
- README: data path, backup and restore, CSV mapping, invoice-number policy, and what an accountant must verify.

# AGENTS.md — Build guide for QuickBooks Online

## Project scope
For simple needs, build invoice creation, payment tracking, expenses, CSV bank import, and basic P&L reports.

Catalogue verdict: no. You can build invoicing and expense tables, but QuickBooks' value is accounting correctness, bank feeds, payroll/tax ecosystem, accountant workflows, compliance, and support.
Use the implementation prompt below to define the deliverable. Complete each phase's acceptance checks before extending the scope.

## Working agreement
- Inspect the repository and its existing instructions before choosing paths, dependencies or commands. Keep one coherent stack and explain changes to the proposed architecture.
- Plan a vertical slice that accepts a real input and produces the useful output described below. Persist only the state the prompt calls for; respect memory-only and upstream-managed workflows. Use fixtures only when they are clearly labelled.
- After scaffolding, document the actual install, development, check and build commands in README and keep them synchronized with the package or project manifest. Do not report commands as successful unless they ran.
- Work in small steps. At handoff, list implemented flows, checks actually performed, remaining blockers, and any credentials or provider setup the owner must supply.
- Do not publish, spend money, contact customers, delete source data or run irreversible migrations without the project owner's authorization.

## Prerequisites
- payment processor
- accounting schema
- bank import/API
- tax/accounting knowledge
- backups
- security

## Stack and architecture
- Node and Express
- better-sqlite3
- Server-rendered HTML
- Printable invoice HTML or PDF

## Security and data integrity
- Bind to localhost and avoid bank credentials
- Keep original import files unchanged
- Use SQLite's backup facility for consistent copies

## Agent implementation rules
- Model money in integer minor units and preserve currency codes
- Make imported data correction and export visible

## Optional agent skills and references
No installable skill is listed for this guide; use the project rules and the stack documentation.

Read the linked SKILL.md and its dependencies before adding a skill. Select only the skills matching this project's runtime and task; their documentation does not supply API access, credentials or approval to perform external actions. Pin the reviewed revision where the tool supports it. Follow the chosen agent's documented project-level installation mechanism.

## Distribution ideas
These are optional planning notes. Obtain the owner's approval before publishing or contacting anyone.
- Position as invoice and expense organization, with accountant review for official books

## Engineering roadmap
1. Implement the ledger schema and local invoice and expense flows.
2. Add CSV mapping, preview, deduplication, and accountant exports.
3. Document tax and accounting boundaries without claiming regulatory correctness.

## Paid-product capabilities outside this build
- bank feeds
- accountant ecosystem
- payroll/tax workflows
- reconciliations
- audit trails
- support
- compliance expectations

## Implementation prompt
Build me a local invoice and expense ledger for a tiny business as a limited substitute for QuickBooks Online. Requirements:

- Use Node, Express, and better-sqlite3 on localhost. Store clients, invoices, line items, payment records, expenses, and import batches in one SQLite file.
- Create invoices with an explicit invoice number, issue date, due date, currency, line items, and user-entered tax amount; render a printable PDF without calculating tax rules.
- Import bank CSV files through a saved column mapping. Show a preview and deduplicate against the same source account, date, amount, and bank transaction identifier when present.
- Record partial payments and show remaining invoice balances. Let me assign expense categories and correct imports without altering the original uploaded file.
- Export invoices, payments, and expenses as separate CSV files for an accountant; show a simple cash-in versus cash-out view labeled as an informal summary.
- Back up the SQLite database with its supported backup API. No accounts, telemetry, payroll, bank feeds, tax filing, or claims of accounting compliance.
- README: data path, backup and restore, CSV mapping, invoice-number policy, and what an accountant must verify.

## Completion evidence
Demonstrate the prompt's acceptance scenarios against the scoped workflow. Include setup from a clean checkout and failure recovery. Check persistence across restart and export/restore only for the state the prompt says to store; for memory-only tools, confirm that temporary content is discarded as specified. Record actual results and remaining limitations. A detailed plan alone does not establish a working replacement.