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invoice-generation

enXure is a self-hosted invoicing and recurring billing app for agencies and freelancers who want to own their billing data instead of renting it from a SaaS. Create invoices and quotes that convert to a real invoice in one click, with recurring billing that runs automatically on each client's own schedule, Stripe/PayPal or manual payment collection, and an optional client portal so clients can view invoices and accept quotes with no login of their own.

Fully brandable (logo, color, white-label mode), with TOTP two-factor auth, a searchable audit log, one-click backups, and a REST API plus Slack/Telegram notifications.

Free and open source (AGPL-3.0) — every core workflow works with no license key; an optional paid license unlocks Stripe/PayPal, recurring billing automation, the client portal, the API, and a few other extras. One container stack (PHP, MySQL, nginx), no Node build step: docker compose up -d --build and you're running.

Open-source Mini ERP demo for German & EU e-invoicing generate and validate ZUGFeRD, XRechnung, Factur-X and EN16931 invoices through the rechnungsapi.de API. Node.js + Express + React, no database, no build step.