billing-automation

name billing-automation description Build automated billing systems for recurring payments, invoicing, subscription lifecycle, and dunning management. Use when implementing subscription billing, automating invoicing, or managing recurring payment systems. Billing Automation Master automated billing systems including recurring billing, invoice generation, dunning management, proration, and tax calculation. When to Use This Skill Implementing SaaS subscription billing Automating invoice generation and delivery Managing failed payment recovery (dunning) Calculating prorated charges for plan changes Handling sales tax, VAT, and GST Processing usage-based billing Managing billing cycles and renewals Core Concepts 1. Billing Cycles Common Intervals: Monthly (most common for SaaS) Annual (discounted long-term) Quarterly Weekly Custom (usage-based, per-seat) 2. Subscription States trial → active → past_due → canceled → paused → resumed 3. Dunning Management Automated process to recover failed payments through: Retry schedules Customer notifications Grace periods Account restrictions 4. Proration Adjusting charges when: Upgrading/downgrading mid-cycle Adding/removing seats Changing billing frequency Quick Start from billing import BillingEngine, Subscription # Initialize billing engine billing = BillingEngine() # Create subscription subscription = billing.create_subscription( customer_id= "cus_123" , plan_id= "plan_pro_monthly" , billing_cycle_anchor=datetime.now(), trial_days= 14 ) # Process billing cycle billing.process_billing_cycle(subscription. id ) Detailed patterns and worked examples Detailed pattern documentation lives in references/details.md . Read that file when the navigation tier above is insufficient.