pnlcs

Open-source WHMCS alternative — self-hosted hosting billing & client portal. Laravel 13 + MySQL. Invoicing, domains, SSL, tickets, reseller, multi-language (30 locales), 15 themes. Free & MIT-licensed. Maintained by Panelica on GitHub, where it has earned 34 stars from the community.

It's actively developed around alpinejs, billing, billing-system, and is a solid reference for anyone building with these tools.