finance-core

Shared library for the Paperfoot accounting suite.

Every finance CLI — invoice-cli, and the forthcoming receipt-cli, expense-cli, bank-cli, recon-cli, ledger-cli, tax-cli — depends on this crate. It owns the things every accounting tool agrees on:

Module	What it owns
money	MinorUnits (i64 cents) + rust_decimal math helpers + discount math.
tax	Jurisdiction enum + TaxProfile for SG / UK / US / EU / Custom.
entity	Issuer — the canonical "company you transact as" primitive.
paths	Canonical suite dirs via ProjectDirs("com", "paperfoot", "accounting").
settings	TOML-backed Settings shared across tools (default_issuer, self_update…).
db	Shared SQLite connection + refinery migrations for the whole suite.
error	CoreError — consumed by each CLI via #[from] on its own error enum.

What a consumer looks like

use finance_core::{db, paths::Paths, settings::Settings};

let paths    = Paths::resolve()?;
let settings = Settings::load(&paths)?;
let conn     = db::open(&paths)?;  // migrations run automatically
// … query `conn` for entities, invoices, receipts, whatever.

One SQLite file lives at Paths::db_file() (e.g. on macOS ~/Library/Application Support/com.paperfoot.accounting/accounting.db) and every tool in the suite reads/writes the same file — so invoice new sees the same default issuer as receipt add, and the ledger is consistent across tools.

Versioning discipline

finance-core owns the schema. To keep bins that pin different versions from corrupting each other:

• Minor bumps (0.1.x → 0.2.0) may add columns, tables, or indexes — never remove or rename. Older bins keep working against the newer schema.
• Major bumps (0.x → 1.0) may change the schema in breaking ways. Every bin must be rebuilt before using the new DB.
• Every consumer CLI's doctor command should refuse to run if the DB schema version is higher than what its pinned finance-core version understands.

License

MIT. See LICENSE.