One HTML file, no build step, no server. Plutus keeps a card per client with contact handles, tags, notes, and a last-contact date, and a payment log under each one with edit, delete, and undo. Several ledgers can live in one data file, each with its own currency.
In Chromium browsers it writes the whole database to a .json file you choose, half a second
after every change; elsewhere it works in browser-only mode with backup and import. The
Insights screen is built from hand-drawn SVG: an explorer that stacks revenue by client over
any window with drill-down and CSV export, plus around twenty charts for trend, cumulative
earnings, top clients, cohorts, gaps between payments, and more.