Leon

Leon is an open-source personal assistant that runs on your own server. It can handle a variety of tasks through modular skills, including billing automation. You install it on a Linux or cloud instance, then enable or build skills for invoicing, payment reminders, or expense tracking. Leon listens for natural language commands and executes them using its plugin system.

Skills are written in JavaScript and can integrate with external APIs like Stripe, PayPal, or QuickBooks. Leon also supports custom triggers and scheduled tasks, making it useful for recurring billing operations. Its conversational interface lets you check payment statuses or generate reports by simply asking. The project uses Node.js and is fully self-hosted, giving you control over data and privacy.

Leon is ideal for developers and sysadmins who want a customizable AI assistant for server-side automation. It is free and open source under the MIT license. You can extend it with your own skills or use community-contributed ones. The project is maintained by the Leon AI community and has a growing library of integrations.