billing-automation

Build automated systems for recurring billing, invoicing, and dunning. Manage subscription lifecycle and proration.

• Automate recurring billing and invoicing
• Manage subscription states and cycles
• Handle failed payments via dunning
• Calculate prorated charges and taxes

• Supports monthly, annual, weekly, and custom billing cycles
• Tracks subscription states: trial → active → past_due → canceled
• Automates invoice generation and delivery
• Manages dunning with retries and notifications
• Handles proration for plan changes and seat adjustments
• Includes tax calculation for sales tax, VAT, GST
• Processes usage-based billing and usage charges

1. 1.Initialize BillingEngine and create subscription
2. 2.Set subscription status (trial, active, past_due, canceled)
3. 3.Process billing cycle with invoice generation and payment attempt
4. 4.Handle payment failure by triggering dunning workflow